Human tasks, or briefly tasks
enable the integration of human beings in service-oriented applications. This
document provides a notation, state diagram and API for human tasks, as well as
a coordination protocol that allows interaction with human tasks in a more
service-oriented fashion and at the same time controls tasks’ autonomy. The
document is called Web Services Human Task (abbreviated to WS-HumanTask for the
rest of this document).
Human tasks are services
“implemented” by people. They allow the integration of humans in
service-oriented applications. A human task has two interfaces. One interface
exposes the service offered by the task, like a translation service or an
approval service. The second interface allows people to deal with tasks, for
example to query for human tasks waiting for them, and to work on these tasks.
A
human task has people assigned to it. These assignments define who should be
allowed to play a certain role on that task. Human tasks might be assigned to
people in a well-defined order. This includes assignments in a specific
sequence and or parallel assignment to a set of people or any combination of
both. Human tasks may also specify how task metadata should be rendered on
different devices or applications making them portable and interoperable with
different types of software. Human tasks can be defined to react to timeouts,
triggering an appropriate escalation action.
This also holds true for notifications. A
notification is a special type of human task that allows the sending of
information about noteworthy business events to people. Notifications are
always one-way, i.e., they are delivered in a fire-and-forget manner: The
sender pushes out notifications to people without waiting for these people to
acknowledge their receipt.
Let us take a look at an example, an approval task. Such a
human task could be involved in a mortgage business process. After the data of
the mortgage has been collected, and, if the value exceeds some amount, a
manual approval step is required. This can be implemented by invoking an
approval service implemented by the approval task. The invocation of the
service by the business process creates an instance of the approval task. As a
consequence this task pops up on the task list of the approvers. One of the
approvers will claim the task, evaluate the mortgage data, and eventually
complete the task by either approving or rejecting it. The output message of
the task indicates whether the mortgage has been approved or not. All of the
above is transparent to the caller of the task (a business process in this
example).
The goal of this specification is to enable portability and
interoperability:
- Portability - The ability to take human tasks and notifications
created in one vendor's environment and use them in another vendor's
environment.
- Interoperability - The capability for multiple components (task
infrastructure, task list clients and applications or processes with human
interactions) to interact using well-defined messages and protocols. This
enables combining components from different vendors allowing seamless
execution.
Out of scope of this specification is how human tasks and
notifications are deployed or monitored. Usually people assignment is
accomplished by performing queries on a people directory which has a certain
organizational model. The mechanism determining how an implementation evaluates
people assignments, as well as the structure of the data in the people
directory is out of scope.
The keywords "MUST", "MUST NOT",
"REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED",
"MAY", and "OPTIONAL" in this document are to be
interpreted as described in RFC 2119 [RFC 2119].
[RFC 1766]
Tags for the Identification of
Languages, RFC 1766, available via http://www.ietf.org/rfc/rfc1766.txt
[RFC 2046]
Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types, RFC 2046, available via http://www.isi.edu/in-notes/rfc2046.txt
(or http://www.iana.org/assignments/media-types/)
[RFC 2119]
Key words for use in RFCs to
Indicate Requirement Levels, RFC 2119, available via http://www.ietf.org/rfc/rfc2119.txt
[RFC 2396]
Uniform Resource Identifiers (URI):
Generic Syntax, RFC 2396,
available via http://www.faqs.org/rfcs/rfc2396.html
[RFC 3066]
Tags for the Identification of
Languages, H. Alvestrand, IETF, January 2001, available via http://www.isi.edu/in-notes/rfc3066.txt
[WSDL 1.1]
Web Services Description Language
(WSDL) Version 1.1, W3C Note, available via http://www.w3.org/TR/2001/NOTE-wsdl-20010315
[WS-Addr-Core]
Web Services Addressing 1.0 - Core, W3C
Recommendation, May 2006, available via http://www.w3.org/TR/ws-addr-core
[WS-Addr-SOAP]
Web Services Addressing 1.0 – SOAP Binding, W3C
Recommendation, May 2006, available via http://www.w3.org/TR/ws-addr-soap
[WS-Addr-WSDL]
Web Services Addressing 1.0 – WSDL Binding, W3C
Working Draft, February 2006, available via http://www.w3.org/TR/ws-addr-wsdl
[WS-C]
OASIS Standard, “Web Services
Coordination (WS-Coordination) Version 1.1”, 16 April 2007, http://docs.oasis-open.org/ws-tx/wstx-wscoor-1.1-spec/wstx-wscoor-1.1-spec.html
[WS-Policy]
Web Services Policy 1.5 -
Framework, W3C Candidate Recommendation 30 March 2007, available via http://www.w3.org/TR/ws-policy/
[WS-PolAtt]
Web Services Policy 1.5 -
Attachment, W3C Candidate Recommendation 30 March 2007, available via http://www.w3.org/TR/2007/CR-ws-policy-attach-20070330/
[XML Infoset]
XML Information Set, W3C Recommendation,
available via http://www.w3.org/TR/2001/REC-xml-infoset-20011024/
[XML Namespaces]
Namespaces in XML 1.0 (Second Edition), W3C
Recommendation, available via http://www.w3.org/TR/REC-xml-names/
[XML Schema Part 1]
XML Schema Part 1: Structures, W3C
Recommendation, October 2004, available via http://www.w3.org/TR/xmlschema-1/
[XML Schema Part 2]
XML Schema Part 2: Datatypes, W3C
Recommendation, October 2004, available via http://www.w3.org/TR/xmlschema-2/
[XMLSpec]
XML Specification, W3C
Recommendation, February 1998, available via http://www.w3.org/TR/1998/REC-xml-19980210
[XPATH 1.0]
XML Path Language (XPath) Version
1.0, W3C Recommendation, November 1999, available via http://www.w3.org/TR/1999/REC-xpath-19991116
There are no non-normative references made by this
specification.
The following conformance targets are defined as part of
this specification
·
WS-HumanTask Definition
A WS-HumanTask Definition is any artifact that complies with the human
interaction schema and additional constraints defined in this document.
·
WS-HumanTask Processor
A WS-HumanTask Processor is any implementation that accepts a WS-HumanTask
definition and executes the semantics as defined in this document.
·
WS-HumanTask Parent
A WS-HumanTask Parent is any implementation that supports the Interoperable
Protocol for Advanced Interactions with Human Tasks as defined in this
document.
·
WS-HumanTask Client
A WS-HumanTask Client is any implementation that uses the Programming
Interfaces of the WS-HumanTask Processor.
One of the motivations of WS-HumanTask was an increasingly
important need to support the ability to allow any application to create human
tasks in a service-oriented manner. Human tasks had traditionally been created
by tightly-coupled workflow management systems (WFMS). In such environments the
workflow management system managed the entirety of a task’s lifecycle, an
approach that did not allow the means to directly affect a task’s lifecycle
outside of the workflow management environment (other than for a human to
actually carry out the task). Particularly significant was an inability to
allow applications to create a human task in such tightly coupled environments.
Figure 1- Architectural Impact
of WS-HumanTask on Workflow Management Systems
The component within a WFMS typically responsible for
managing a task’s lifecycle (aka workitem) is called a Workitem Manager.
An example of such an environment is depicted on the left portion of Figure 1.
The right portion of the figure depicts how significant a change of
architecture WS-HumanTask represents. Using this approach, the WFMS no longer
incorporates a workitem manager but rather interacts with a Task Processor.
In this architecture the Task Processor is a separate, standalone component
exposed as a service, allowing any requestor to create tasks and interact with
tasks. It is the Task Processor’s role to manage its tasks’ lifecycle and to
provide the means to “work” on tasks.
Conversely, by separating the Task Processor from the WFMS
tasks can be used in the context of a WFMS or any other WS-HumanTask application
(also referred to as the Task Parent). A (special) case of a business
process acting as a Task Parent of a human task is described by the BPEL4People
specification.
WS-HumanTask tasks are assumed to have an interface. The
interface of a task is represented as an application-dependent port type
referred to as its Task Definition specific interface (or interface
for short – see section 4.2). In order to create task instances (or tasks
for short) managed by a particular Task Processor, a port implementing the port
type corresponding to a task needs to be deployed into the Task Processor
before it can be invoked. See Figure 2 depicting a Task Definition associated
with a port type pT).
Figure 2 - Task
Definitions Deployed in Task Processor
Once a task is available on the task processor any requestor
can create task instances and interact with them. The requestor that creates a
task is referred to as the Task Parent. A task instance is created by
invoking an operation of the port type representing the interface of the task
to be created. Typically port types expose a single operation. Where more than
one operation is defined, which operation of the port type to be used to create
a task is outside the scope of WS-HumanTask.
Figure 3 - Instantiating
Tasks
In workflow environments the lifecycle of a task is
typically dependent on the workflow system - i.e. tasks have to give up some of
their autonomy. For example when a workflow is terminated prematurely, task
initiated by that workflow should not be allowed to continue - the
corresponding efforts to continue the work of the task would otherwise be
wasted. To automate the corresponding behavior ensuring that the lifecycle of a
Task Parent and the lifecycles of its initiated tasks are tightly coupled,
WS-HumanTask uses the WS-Coordination specification as its coordination
framework. This requires the definition of a coordination protocol following a
particular behavior (see section 8). This is depicted by Figure 4.
When the Task Parent creates a task using the specific
operation op() of a port of port type pT, coordination context information is
passed by the Task Parent to the environment hosting that port. Like any other
WS-Coordination compliant coordination context, it contains the endpoint
reference of (i.e. a “pointer” to) the coordinator to be used by the recipient
of the context to register the corresponding coordination type. Note that for
simplicity we assume in Figure 4 that the Task Processor itself is this
recipient of the context information. Upon reception of the coordination
context the Task Processor will register with the coordinator, implying that it
passes the endpoint reference of its protocol handler to the coordinator (see
section 8). In turn it will receive the endpoint reference of the protocol
handler of the Task Parent. Similarly, for simplicity we assume in Figure 4
that the task parent provides its protocol handler. From that point on a
coordination channel is established between the Task Parent and the Task
Processor to exchange protocol messages allowing the coupling of the lifecycles
of a task with its Task Parent. Section 4.10 describes the lifecycle of a task
in more detail.
Figure 4 - Establishing
a Protocol Channel
Most often tasks are long running in nature and will be
invoked in an asynchronous manner. Thus, the Task Parent will kick-off the task
and expects the result of the task to be returned at a later point in time. In
order to allow the ability to pass the results back, the Task Processor needs
to know where to send these results. For this purpose the context is extended
with additional metadata that specifies the endpoint reference to be used to
pass the result to, as well as the operation of the endpoint to be used by the
Task Processor. Figure 5 depicts this by showing that the context contains
information pointing to a port of port type pt’ and specifying the name of the
operation op’ to be used on that port for returning results. Note that this
behavior is compliant to WS-Addressing.
Figure 5 - Passing Callback
Information for Long Running Tasks
Finally, a Task Parent application invoking an operation
implemented by a task is allowed to pass additional data along with the request
message. This data is called the human task context and allows the
ability to override some of the Task Definition’s elements. Conversely,
a human task context is also passed back with the response message, propagating
information from the completed task to the Task Parent application, such as the
task outcome or the task’s actual people assignments.
Once a task is created it can be presented to its
(potential) owners to be claimed and worked on. For that purpose another type
of application called a Task Client is typically used. A Task Client
presents to each of its users the tasks available to them. Users can then
decide to claim the task to carry out the work associated with it. Other
functions typically offered by a Task Client include the ability to skip a
task, to add comments or attachments to a task, to nominate other users to
perform the task and that like. In order to enable a Task Client to perform
such functions on tasks, WS-HumanTask specifies the task client interface
required to be implemented by Task Processor to support Task Clients (see
section 7.1). Figure 6 depicts the resultant architecture stemming from the
introduction of Task Clients.
Figure 6 - Task
List Client and Corresponding Interface
Once a user selects a task using his or her Task Client the
user interface associated with the task is rendered allowing the user to view
application-specific information pertaining to the task. WS-HumanTask does not
specify such rendering but provides the means using a container to
provide rendering hints to Task Clients. A Task Client in turn uses this
information to construct or initiate the construction of the user interface of
the task - the details how this is achieved are out of scope of WS-HumanTask.
In the case of Lean Tasks, that rendering may be generated by the Task
Processor. From the perspective of the Task Client, the fact the task is a Lean
Task need not be apparent. Furthermore, the task may require the use of
business applications to complete the task. Again the use of such business
applications is out of scope of WS-HumanTask but such applications and their
use are nonetheless important to the overall architecture depicted in Figure 7.
Figure 7 - Overall
Architecture of a Human Task Infrastructure
The container referred to above for rendering a task’s
information is a task’s <rendering>
element (see section 4.4). A rendering element specifies its type, expressed as
a QName that denotes the kind of rendering mechanism to use to generate the
user interface for the task. All information actually needed to create the user
interface of the task is provided by the elements nested within the task’s
rendering element (see Figure 8). The nested elements may also provide
information about a business application required to complete the task and
other corresponding parameters.
Figure 8 - Potential
Renderings of a Task
For example Figure 9 depicts a rendering of type
my:HTMLform. Its QName denotes that HTML forms processing capabilities is
needed to render the corresponding user interface of the task enclosing this
rendering. The nested element of the my:HTMLform rendering contains the actual
HTML form to be rendered. The example further assumes that the forms processor
understands the {$...} notation (see section 4.3) to provide values from the
task input as data presented in the form.
Figure 9 - Sample
Rendering of a Task
A task may have different renderings associated with it.
This allows the ability for a task to be rendered by different access
mechanisms or adapt to user preferences for example. How information is
rendered is out of scope of the WS-HumanTask specification.
The language introduces a grammar for describing human tasks
and notifications. Both design time aspects, such as task properties and
notification properties, and runtime aspects, such as task states and events
triggering transitions between states are covered by the language. Finally, it
introduces a programming interface which can be used by applications involved
in the life cycle of a task to query task properties, execute the task, or
complete the task. This interface helps to achieve interoperability between
these applications and the task infrastructure when they come from different
vendors.
The language provides an extension mechanism that can be
used to extend the definitions with additional vendor-specific or
domain-specific information.
Throughout this specification, WSDL and schema elements may
be used for illustrative or convenience purposes. However, in a situation where
those elements or other text within this document contradict the separate
WS-HumanTask, WSDL or schema files, it is those files that have precedence and
not this document.
WS-HumanTask utilizes the following specifications:
·
WSDL 1.1
·
XML Schema 1.0
·
XPath 1.0
·
WS-Addressing 1.0
·
WS-Coordination 1.1
·
WS-Policy 1.5
WS-HumanTask references these namespaces:
·
wsa – http://www.w3.org/2005/08/addressing
·
wsdl – http://schemas.xmlsoap.org/wsdl/
·
wsp – http://www.w3.org/ns/ws-policy
·
xsd – http://www.w3.org/2001/XMLSchema
The WS-HumanTask extensibility mechanism allows:
·
Attributes from other namespaces to appear on any WS-HumanTask
element
·
Elements from other namespaces to appear within WS-HumanTask
elements
Extension attributes and extension elements MUST NOT
contradict the semantics of any attribute or element from the WS-HumanTask
namespace. For example, an extension element could be used to introduce a new
task type.
The specification differentiates between mandatory and
optional extensions (the section below explains the syntax used to declare
extensions). If a mandatory extension is used, a compliant implementation has
to understand the extension. If an optional extension is used, a compliant
implementation can ignore the extension.
Human interactions subsume both human tasks and
notifications. While human tasks and notifications are described in subsequent
sections, this section explains the overall structure of human interactions
definition.
<htd:humanInteractions
xmlns:htd="http://docs.oasis-open.org/ns/bpel4people/ws-humantask/200803"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:tns="anyURI"
targetNamespace="anyURI"
expressionLanguage="anyURI"?
queryLanguage="anyURI"?>
<htd:extensions>?
<htd:extension namespace="anyURI"
mustUnderstand="yes|no"/>+
</htd:extensions>
<htd:import namespace="anyURI"?
location="anyURI"?
importType="anyURI" />*
<htd:logicalPeopleGroups>?
<htd:logicalPeopleGroup name="NCName" reference="QName"?>+
<htd:parameter name="NCName"
type="QName" />*
</htd:logicalPeopleGroup>
</htd:logicalPeopleGroups>
<htd:tasks>?
<htd:task name="NCName">+
...
</htd:task>
</htd:tasks>
<htd:notifications>?
<htd:notification name="NCName">+
...
</htd:notification>
</htd:notifications>
</htd:humanInteractions>
The <humanInteractions>
element has the following properties:
·
expressionLanguage:
This attribute specifies the expression language used in the enclosing
elements. The default value for this attribute is urn:ws-ht:sublang:xpath1.0
which represents the usage of XPath 1.0 within human interactions definition. A
WS-HumanTask Definition that uses expressions MAY override the default
expression language for individual expressions. A WS-HumanTask Processor MUST
support the use of XPath 1.0 as the expression language.
·
queryLanguage:
This attribute specifies the query language used in the enclosing elements. The
default value for this attribute is urn:ws-ht:sublang:xpath1.0
which represents the usage of XPath 1.0 within human interactions definition. A
WS-HumanTask Definition that use query expressions MAY override the default
query language for individual query expressions. A WS-HumanTask Processor MUST
support the use of XPath 1.0 as the query language.
·
extensions: This
element is used to specify namespaces of WS-HumanTask extension attributes and
extension elements. The element is optional. If present, it MUST include at
least one extension element. The <extension> element is
used to specify a namespace of WS-HumanTask extension attributes and extension
elements, and indicate whether they are mandatory or optional. Attribute mustUnderstand
is used to specify whether the extension must be understood by a compliant
implementation. If the attribute has value “yes” the extension is mandatory.
Otherwise, the extension is optional. If a WS-HumanTask Processor does not
support one or more of the extensions with mustUnderstand="yes",
then the human interactions definition MUST be rejected. A WS-HumanTask
Processor MAY ignore optional extensions. A WS-HumanTask Definition MAY declare
optional extensions. The same extension URI MAY be declared multiple times in
the <extensions> element. If an extension URI is identified as
mandatory in one <extension> element and optional in another,
then the mandatory semantics have precedence and MUST be enforced by a
WS-HumanTask Processor. The extension declarations in an <extensions>
element MUST be treated as an unordered set.
·
import: This
element is used to declare a dependency on external WS-HumanTask and WSDL
definitions. Zero or more <import>
elements MAY appear as children of the <humanInteractions>
element.
The namespace
attribute specifies an absolute URI that identifies the imported definitions.
This attribute is optional. An <import>
element without a namespace attribute indicates that external definitions are
in use which are not namespace-qualified. If a namespace is specified then the
imported definitions MUST be in that namespace. If no namespace is specified
then the imported definitions MUST NOT contain a targetNamespace specification.
The namespace http://www.w3.org/2001/XMLSchema
is imported implicitly. Note, however, that there is no implicit XML Namespace
prefix defined for http://www.w3.org/2001/XMLSchema.
The location
attribute contains a URI indicating the location of a document that contains
relevant definitions. The location
URI MAY be a relative URI, following the usual rules for resolution of the URI
base [XML Base, RFC 2396]. The location
attribute is optional. An <import>
element without a location
attribute indicates that external definitions are used by the human
interactions definition but makes no statement about where those definitions
can be found. The location
attribute is a hint and a WS-HumanTask Processor is not required to retrieve
the document being imported from the specified location.
The mandatory importType attribute identifies the
type of document being imported by providing an absolute URI that identifies
the encoding language used in the document. The value of the importType attribute MUST be set to http://docs.oasis-open.org/ns/bpel4people/ws-humantask/200803
when importing human interactions definitions, to http://schemas.xmlsoap.org/wsdl/ when importing WSDL 1.1
documents or to http://www.w3.org/2001/XMLSchema
when importing XML Schema documents.
According to these rules, it is
permissible to have an <import>
element without namespace and location attributes, and only
containing an importType
attribute. Such an <import>
element indicates that external definitions of the indicated type are in use
that are not namespace-qualified, and makes no statement about where those
definitions can be found.
A WS-HumanTask Definition MUST
import all other WS-HumanTask definitions, WSDL definitions, and XML Schema
definitions it uses. In order to support the use of definitions from namespaces
spanning multiple documents, a WS-HumanTask Definition MAY include more than
one import declaration for the same namespace
and importType, provided that
those declarations include different location values. <import> elements are conceptually unordered. A
WS-HumanTask Processor MUST reject the imported documents if they contain
conflicting definitions of a component used by the imported WS-HumanTask
Definition.
Documents (or namespaces) imported
by an imported document (or namespace) MUST NOT be transitively imported by a WS-HumanTask
Processor. In particular, this means that if an external item is used by a task
enclosed in the WS-HumanTask Definition, then a document (or namespace) that
defines that item MUST be directly imported by the WS-HumanTask Definition.
This requirement does not limit the ability of the imported document itself to
import other documents or namespaces.
·
logicalPeopleGroups:
This element specifies a set of logical people groups. The element is optional.
If present, it MUST include at least one logicalPeopleGroup
element. The set of logical people groups MUST contain only those logical
people groups that are used in the humanInteractions element, and
enclosed human tasks and notifications. The
logicalPeopleGroup element has the following attributes. The name attribute specifies
the name of the logical people group. The name MUST be unique among the names
of all logicalPeopleGroups defined within the humanInteractions element. The reference attribute is optional.
In case a logical people group used in the humanInteractions element is defined
in an imported WS-HumanTask definition, the reference attribute MUST be used to
specify the logical people group. The parameter
element is used to pass data needed for people query evaluation.
·
tasks: This
element specifies a set of human tasks. The element is optional. If present, it
MUST include at least one <task> element. The
syntax and semantics of the <task> element are
introduced in section 4 “Human Tasks”.
·
notifications:
This element specifies a set of notifications. The element is optional. If
present, it MUST include at least one <notification> element.
The syntax and semantics of the <notification> element
are introduced in section 6 “Notifications”.
·
Element humanInteractions
MUST NOT be empty, that is it MUST include at least one element.
All elements in WS-HumanTask Definition MAY use the element <documentation> to
provide annotation for users. The content could be a plain text, HTML, and so
on. The <documentation>
element is optional and has the following syntax:
<htd:documentation xml:lang="xsd:language">
...
</htd:documentation>
The
XPath 1.0 specification [XPATH 1.0] defines the context in which an XPath
expression is evaluated. When XPath 1.0 is used as an Expression Language in
WS-HumanTask language elements then the XPath context is initialized as
follows:
- Context node: none
- Context position: none
- Context size: none
- Variable bindings: none
- Function library: Core XPath 1.0 and WS-HumanTask
functions MUST be available and processor-specific functions MAY be
available
- Namespace declaration: all in-scope namespace declarations
from the enclosing element
Note that XPath 1.0 explicitly requires that any element or
attribute used in an XPath expression that does not have a namespace prefix
must be treated as being namespace unqualified. As a result, even if there is a
default namespace defined on the enclosing element, the default namespace will
not be applied.
Generic human roles define what a person or a group of
people resulting from a people query can do with tasks and notifications. The
following generic human roles are taken into account in this specification:
·
Task initiator
·
Task stakeholders
·
Potential owners
·
Actual owner
·
Excluded owners
·
Business administrators
·
Notification recipients
A task initiator is the person who creates the task
instance. A WS-HumanTask Definition MAY define assignment for this generic
human role. Depending on how the task has been instantiated the task initiator
can be defined.
The task stakeholders are the people ultimately
responsible for the oversight and outcome of the task instance. A task
stakeholder can influence the progress of a task, for example, by adding ad-hoc
attachments, forwarding the task, or simply observing the state changes of the
task. It is also allowed to perform administrative actions on the task
instance and associated notification(s), such as resolving missed deadlines. A
WS-HumanTask Definition MAY define assignment for this generic human role.
WS-HumanTask Processors MUST ensure that at least one person is associated with
this role at runtime.
Potential owners of a task are persons who receive
the task so that they can claim and complete it. A potential owner becomes the actual
owner of a task by explicitly claiming it. Before the task has been
claimed, potential owners can influence the progress of the task, for example
by changing the priority of the task, adding ad-hoc attachments or comments.
All excluded owners are implicitly removed from the set of potential owners. A
WS-HumanTask Definition MAY define assignment for this generic human role.
Excluded owners are are people who cannot become an
actual or potential owner and thus they cannot reserve or start the task. A
WS-HumanTask Definition MAY define assignment for this generic human role.
An actual owner of a task is the person actually
performing the task. When task is performed, the actual owner can execute
actions, such as revoking the claim, forwarding the task, suspending and
resuming the task execution or changing the priority of the task. A WS-HumanTask
Definition MUST NOT define assignment for this generic human role.
Business administrators play the same role as task
stakeholders but at task definition level. Therefore, business administrators
can perform the exact same operations as task stakeholders. Business
administrators can also observe the progress of notifications. A WS-HumanTask
Definition MAY define assignment for this generic human role. WS-HumanTask
Processors MUST ensure that at runtime at least one person is associated with
this role.
Notification recipients are persons who receive the
notification, such as happens when a deadline is missed or when a milestone is
reached. This role is similar to the roles potential owners and actual owner
but has different repercussions because a notification recipient does not have
to perform any action and hence it is more of informational nature than
participation. A notification has one or more recipients. A WS-HumanTask
Definition MAY define assignment for this generic human role.
A human task may
describe complex work that can be divided into a substructure of related, but
independent operations with potential work being carried out by different
parties.
Complex tasks
with substructures are called composite tasks; they can be considered as a
composition of multiple (sub) tasks.
A sub task
describes an act that may or must be completed as part of completing a larger
and more complex task. The enclosing composite task may share data with
embedded sub tasks, e.g. map data into the input structure of sub tasks or
share attachments between composite and sub task.
Composite tasks
follow the design principle that they are managed by a single task processor.
In general sub tasks are human
tasks, inheriting all attributes that a human task has, and each behaving the
way that a human task does. Some specialties in the area of people assignment
and state transitions apply in case a task is a sub task, to align with the
behavior of the superior composite task.
Tasks can be
composite tasks by definition (sub tasks are already defined in the task model)
or turn into composite tasks at runtime when a task processor creates in an
ad-hoc manner one or more sub tasks to structure work.
In case a composite task is pre-defined as
such, the task model contains the definition of one or more sub tasks.
Composite tasks come with the following additional attributes:
·
Composition Type (parallel | sequential)
Composite tasks
with composition type “parallel” allow multiple active sub tasks at the same
time; sub tasks are not in any order; composite tasks with composition type
“sequential” only allow sequential creation of sub tasks in the pre-defined
order (a second listed sub task must not be created before a first listed sub
task has been terminated).
·
Creation Pattern (manual | automatic)
Composite tasks
with activation pattern “manual” expect the ”actual owner” to trigger creation
of pre-defined sub tasks; composite tasks with activation pattern “automatic”
are automatically created at the time the composite task’s status becomes “in
progress” (where composition type is “parallel” all pre-defined sub tasks are
created at the time the composite task’s status becomes “in progress”; where
composition type is “sequential” at the time the composite task’s status
becomes “in progress” the first defined sub task will be created; the next sub
task in a sequence is automatically created when its predecessor is
terminated).
An ordinary task may turn into a composite task when the
actual owner of a task decides to substructure his work and create sub tasks
ad-hoc at runtime.
These sub tasks created at runtime behave and are treated as
though they are of type “parallel” (a user may create multiple sub tasks at a
time) and have an activation pattern of “manual” (creation of ad-hoc sub tasks
is always triggered by a user).
A Routing Pattern is a special form of potential owner
assignment in which a Task is assigned to people in a well-defined order.
Routing patterns allow the assignment of a Task in sequence or parallel. The
htd:parallel element defines a parallel routing pattern and the htd:sequence
element defines a sequential routing pattern. Those patterns MAY be used in any
combination to create complex task routing to people. Routing patterns can be
used in both tasks and sub tasks.
The complex people assignment used to describe Routing
Patterns is a specific syntatic version of Composite Tasks. It is a convenient
syntax to decribe the "who" in a composite task scenario. The
composite task syntax is more expressive to describe the "what" in
the sense of which different subtasks are executed.
A composite task, including subtasks of different task
types, can be described only using the composite task syntax. A routing task
containing a dynamic number of subtasks derived from the cardinality of the set
of assigned people can be described only using the routing task syntax.
Both syntatic flavors may be used in combination which means
that a composite task type may include a complex people assignment and that any
task defining a complex people assignment may become a composite task at
runtime when creating adhoc subtasks.
The runtime instantiation model and observable behavior for
task instances is identical when using one or the other syntatic flavor.
To determine who is responsible for acting on a human task
in a certain generic human role or who will receive a notification, people need
to be assigned. People assignment can be achieved in different ways:
·
Via logical people groups (see 3.5.1 “Using Logical People Groups”)
·
Via literals (see 3.5.2 “Using Literals”)
·
Via expressions e.g., by retrieving data from the input message
of the human task (see 3.5.3 “Using Expressions”).
·
In a well-defined order using Routing Patterns (see Routing
Patterns)
When specifying people assignments then the data type htt:tOrganizationalEntity is used. The
htt:tOrganizationalEntity
element specifies the people assignments associated with generic human roles
used.
Human tasks might be assigned to people in a well-defined
order. This includes assignments in a specific sequence and or parallel
assignment to a set of people or any combination of both.
Syntax:
<htd:peopleAssignments>
<htd:genericHumanRole>+
<htd:from>...</htd:from>
</htd:genericHumanRole>
<htd:potentialOwners>+
fromPattern+
</htd: potentialOwners>
</htd:peopleAssignments>
The following syntactical
elements for generic human roles are introduced. They can be used wherever the
abstract element genericHumanRole is allowed by the WS-HumanTask XML Schema.
<htd:excludedOwners>
<htd:from>...</htd:from>
</htd:excludedOwners>
<htd:taskInitiator>
<htd:from>...</htd:from>
</htd:taskInitiator>
<htd:taskStakeholders>
<htd:from>...</htd:from>
</htd:taskStakeholders>
<htd:businessAdministrators>
<htd:from>...</htd:from>
</htd:businessAdministrators>
<htd:recipients>
<htd:from>...</htd:from>
</htd:recipients>
For the potentialOwner
generic human role the syntax is as following
<htd:potentialOwner>
fromPattern+
</htd:potentialOwner>
where fromPattern
is one of:
<htd:from>
... </htd:from>
<htd:sequence
type="all|single"?>
fromPattern*
</htd:sequence>
<htd:parallel
type="all|single"?>
fromPattern*
</htd:parallel>
Element <htd:from>
is used to specify the value to be assigned to a
role. The element has different forms as described below.
A logical people group represents one person, a set
of people, or one or many unresolved groups of people (i.e., group names). A
logical people group is bound to a people query against a people directory at
deployment time. Though the term query is used, the exact discovery and
invocation mechanism of this query is not defined by this specification. There
are no limitations as to how the logical people group is evaluated. At runtime,
this people query is evaluated to retrieve the actual people assigned to the
task or notification. Logical people groups MUST support query parameters which
are passed to the people query at runtime. Parameters MAY refer to task
instance data (see section 3.8 for more details). During people query execution
a WS-HumanTask Processor can decide which of the parameters defined by the
logical people group are used. A WS-HumanTask Processor MAY use zero or more of
the parameters specified. It MAY also override certain parameters with values
defined during logical people group deployment. The deployment mechanism for
tasks and logical people groups is out of scope for this specification.
A logical people group has one instance per set of unique
arguments. Whenever a logical people group is referenced for the first time
with a given set of unique arguments, a new instance MUST be created by the
WS-HumanTask Processor. To achieve that, the logical people group MUST be
evaluated / resolved for this set of arguments. Whenever a logical people group
is referenced for which an instance already exists (i.e., it has already been
referenced with the same set of arguments), the logical people group MAY be
re-evaluated/re-resolved.
In particular, for a logical people group with no
parameters, there is a single instance, which MUST be evaluated / resolved when
the logical people group is first referenced, and which MAY be re-evaluated /
re-resolved when referenced again.
People queries are evaluated during the creation of a human
task or a notification. If a people query fails a WS-HumanTask Processor MUST
create the human task or notification anyway. Failed people queries MUST be
treated like people queries that return an empty result set. If the potential
owner people query returns an empty set of people a WS-HumanTask Processor MUST
perform nomination (see section 4.10.1 “Normal processing of a Human Task”). In
case of notifications a WS-HumanTask Processor MUST apply the same to
notification recipients.
People queries return one person, a set of people, or the
name of one or many groups of people. The use of a group enables the ability to
create a human "work queue" where members are provided access to work
items assigned to them as a result of their membership of a group. The ability
to defer group membership is beneficial when group membership changes
frequently.
Logical people groups are global elements enclosed in a
human interactions definition document. Multiple human tasks in the same
document can utilize the same logical people group definition. During
deployment each logical people group is bound to a people query. If two human
tasks reference the same logical people group, they are bound to the same
people query. However, this does not guarantee that the tasks are actually
assigned to the same set of people. The people query is performed for each
logical people group reference of a task and can return different results, for
example if the content of the people directory has been changed between two
queries. Binding of logical people groups to actual people query
implementations is out of scope for this specification.
Syntax:
<htd:from logicalPeopleGroup="NCName">
<htd:argument name="NCName" expressionLanguage="anyURI"? >*
expression
</htd:argument>
</htd:from>
The
logicalPeopleGroup attribute
refers to a logicalPeopleGroup definition. The element <argument> is used to pass values used in the
people query. The expressionLanguage
attribute specifies the language used in the expression. The attribute is
optional. If not specified, the default language as inherited from the closest
enclosing element that specifies the attribute MUST be used by WS-HumanTask
Processor.
Example:
<htd:potentialOwners>
<htd:from logicalPeopleGroup="regionalClerks">
<htd:argument name="region">
htd:getInput("part1")/region
</htd:argument>
</htd:from>
</htd:potentialOwners>
People assignments can be defined literally by directly
specifying the user identifier(s) or the name(s) of groups using either the htt:tOrganizationalEntity or htt:tUser data type introduced below
(see 3.5.4 “Data Type for Organizational Entities”).
Syntax:
<htd:from>
<htd:literal>
... literal value ...
</htd:literal>
</htd:from>
Example specifying user identifiers:
<htd:potentialOwners>
<htd:from>
<htd:literal>
<htt:organizationalEntity>
<htt:user>Alan</htt:user>
<htt:user>Dieter</htt:user>
<htt:user>Frank</htt:user>
<htt:user>Gerhard</htt:user>
<htt:user>Ivana</htt:user>
<htt:user>Karsten</htt:user>
<htt:user>Matthias</htt:user>
<htt:user>Patrick</htt:user>
</htt:organizationalEntity>
</htd:literal>
</htd:from>
</htd:potentialOwners>
Example
specifying group names:
<htd:potentialOwners>
<htd:from>
<htd:literal>
<htt:organizationalEntity>
<htt:group>bpel4people_authors</htt:group>
</htt:organizationalEntity>
</htd:literal>
</htd:from>
</htd:potentialOwners>
Alternatively people can be assigned using expressions
returning either an instance of the htt:tOrganizationalEntity
data type or the htt:tUser data
type introduced below (see 3.5.4 “Data Type for Organizational Entities”).
Syntax:
<htd:from expressionLanguage="anyURI"?>
expression
</htd:from>
The
expressionLanguage attribute
specifies the language used in the expression. The attribute is optional. If
not specified, the default language as inherited from the closest enclosing
element that specifies the attribute MUST be used by WS-HumanTask Processor.
Example:
<htd:potentialOwners>
<htd:from>htd:getInput("part1")/approvers</htd:from>
</htd:potentialOwners>
<htd:businessAdministrators>
<htd:from>
htd:except(
htd:getInput("part1")/admins,
htd:getInput("part1")/globaladmins[0] )
</htd:from>
</htd:businessAdministrators>
The following XML schema definition describes the format of
the data that is returned at runtime when evaluating a logical people group.
The result can contain either a list of users or a list of groups. The latter
is used to defer the resolution of one or more groups of people to a later
point, such as when the user accesses a task list.
<xsd:element name="organizationalEntity" type="tOrganizationalEntity" />
<xsd:complexType name="tOrganizationalEntity">
<xsd:choice maxOccurs="unbounded">
<xsd:element name="user" type="tUser" />
<xsd:element name="group" type="tGroup" />
</xsd:choice>
</xsd:complexType>
<xsd:element name="user" type="tUser" />
<xsd:simpleType name="tUser">
<xsd:restriction base="xsd:string" />
</xsd:simpleType>
<xsd:element name="group" type="tGroup" />
<xsd:simpleType name="tGroup">
<xsd:restriction base="xsd:string" />
</xsd:simpleType>
3.5.5 Subtasks
Like a task, a sub task has a set of
generic human roles. In case people assignment to a sub task’s roles is not
defined (neither in the sub task’s task definition nor on composite task level
(using overwrite mechanisms)) the following default assignments apply
(especially valid for ad-hoc scenarios):
·
Task initiator
a) Activation
pattern “manual” à WS-HumanTask
Processor MAY assign the actual owner of the composite task
b) Activation
pattern “automatic” à WS-HumanTask
Processor MAY assign the initiator of the composite task
·
Task stakeholders
o
A WS-HumanTask Processor MAY assign the actual owner of the
composite task
·
Potential owners
o
No default assignment (usually potential owners will explicitly
be defined)
·
Excluded owners
o
A WS-HumanTask Processor MUST assign the excluded owners of the composite
task
(This rule applies always, even though
the excluded owners of a sub task may be enhanced by additional people)
·
Business administrators
o
A WS-HumanTask Processor MAY assign the business administrators
of the composite task
3.6 Task Rendering
Humans require a presentation interface to interact with a
machine. This specification covers the service interfaces that enable this to
be accomplished, and enables this in different constellations of software from
different parties. The key elements are the task list client, the task
processor and the applications invoked when a task is executed.
It is assumed that a single task instance can be rendered by
different task list clients so the task engine does not depend on a single
dedicated task list client. Similarly it is assumed that one task list client
can present tasks from several task engines in one homogenous list and can
handle the tasks in a consistent manner. The same is assumed for notifications.
A distinction is made between the rendering of the meta-information
associated with the task or notification (task-description UI and
task list UI) (see section 4.3 for more details on presentation elements)
and the rendering of the task or notification itself (task-UI) used for
task execution (see section 4.4 for more details on task rendering). For
example, the task-description UI includes the rendering of a summary list of
pending or completed tasks and detailed meta-information such as a deadlines,
priority and description about how to perform the task. It is the task list
client that deals with this.
The task-UI can be rendered by the task list client or
delegated to a rendering application invoked by the task list client. The task
definition and notification definition can define different rendering
information for the task-UI using different rendering methodologies.
Versatility of deployment determines which software within a
particular constellation performs the presentation rendering.
The task-UI can be specified by a rendering method within
the task definition or notification definition. The rendering method is
identified by a unique name attribute and specifies the type of rendering
technology being used. A task or a notification can have more than one such
rendering method, e.g. one method for each environment the task or notification
is accessed from (e.g. workstation, mobile device).
The task-list UI encompasses all information crucial for
understanding the importance of and details about a given task or notification
(e.g. task priority, subject and description) - typically in a table-like
layout. Upon selecting a task, i.e. an entry in case of a table-like layout,
the user is given the opportunity to launch the corresponding task-UI. The task-UI
has access to the task instance data, and can comprise and manipulate documents
other than the task instance. It can be specified by a rendering method within
the task description.
WS-HumanTask enables the creation of task applications with
rich renderings, separate input and output messages, and custom business logic
in the portType implementation. However, in the spectrum of possible tasks,
from enterprise-wide formal processes to department-wide processes to team
specific processes to individual, ad-hoc assignments of work, there are
scenarios where the task can be defined simply with metadata and the rendering
can be left to the WS-HumanTask Processor. An example of this is a simple to-do
task, where no form is required beyond the acknowledgement by the actual owner
that the work stated in the name, subject, and description of the task is done.
A notification doesn’t work in this case since it lacks the ability to track
whether the work is done or not, and defining a task with a WSDL and portType
is beyond the capabilities of those requiring the work done, such as in a team
or individual scenario. Therefore, having a way to define the work required of
the task in a simpler way enables a greater breadth of scenarios for these
smaller scoped types.
A Lean Task is a task that has a reduced set of
vendor-specific capabilities which results in increased portability and
simplicity. The two pieces of the task XML definition that Lean Tasks lack are
the ability to define renderings and custom port types. Throughout the
specification uses of the word task refers to both types of tasks unless
otherwise noted.
When used in constellation 4 of WS-BPEL4People, a Lean Task
MUST be started through pre-existing interfaces that do not vary in portType or
operation per task. The port and operation MUST instead be shipped as part of
the installation of the WS-HumanTask Processor (see section 1.4). Therefore, they also lack the ability to define which portType and operation are used to
start the task as part of its XML definition. Instead, a Lean Task uses a
sub-element that describes the input message (and a symmetrical output
message).
While a lean task can have one or more renderings explicitly
defined, if it defines zero renderings, the schema of the input message and its
contained hints for rendering MUST instead be used.
All other WS-HumanTask Client to WS-HumanTask Processor
interactions behave exactly as before, implying that the processing of a task
on a WS-HumanTask Processor for a Lean Task and for a non-Lean Task MUST be
indistinguishable from the perspective of a WS-HumanTask Client.
3.8 Task Instance Data
Task instance data falls into three categories:
·
Presentation data – The data is derived from the task definition
or the notification definition such as the name, subject or description.
·
Context data - A set of dynamic properties, such as priority,
task state, time stamps and values for all generic human roles.
·
Operational data – The data includes the input message, output
message, attachments and comments.
The presentation data is used, for example, when displaying
a task or a notification in the task list client. The presentation data has
been prepared for display such as by substituting variables. See section 4.3 “Presentation Elements” for more details.
The task context includes the following:
·
Task state
·
Priority
·
Values for all generic human roles, i.e. potential owners, actual
owner and business administrators
·
Time stamps such as start time, completion time, defer expiration
time, and expiration time
·
Skipable indicator
A WS-HumanTask Processor MAY extend this set of properties
available in the task context. For example, the actual owner might start the
execution of a task but does not complete it immediately, in which case ann
intermediate state could be saved in the task context.
The operational data of a task consists of its input data
and output data or fault data, as well as any ad-hoc attachments and comments.
The operational data of a notification is restricted to its input data.
Operational data is accessed using the XPath extension functions and
programming interface.
A WS-HumanTask Processor MAY allow arbitrary additional data
to be attached to a task. This additional data is referred to as task ad-hoc
attachments. An ad-hoc attachment is specified by its name, its type and
its content and a system-generated attachment identifier.
The contentType
of an attachment can be any valid XML schema type, including xsd:any, or any
MIME type. The attachment data is assumed to be of that specified content type.
The contentCategory
of an attachment is a URI used to qualify the contentType. While contentType
contains the type of the attachment, the contentCategory specifies the type
system used when defining the contentType. Predefined values for
contentCategory are
- "http://www.w3.org/2001/XMLSchema";
if XML Schema types are used for the contentType
- "http://www.iana.org/assignments/media-types/";
if MIME types are used for the contentType
The set of values is extensible. A WS-HumanTask Processor
MUST support the use of XML Schema types and MIME types as content categories,
indicated by the predefined URI values shown above.
The accessType
element indicates if the attachment is specified inline or by reference. In the
inline case it MUST contain the string constant “inline”. In this case the value of the attachment data type contains the base64 encoded
attachment. In case the attachment is referenced it MUST contain the string
“URL”, indicating that the value
of the attachment data type contains a URL from where the attachment can be
retrieved. Other values of the accessType
element are allowed for extensibility reasons, for example to enable inclusion
of attachment content from content management systems.
The attachedTime
element indicates when the attachment is added.
The attachedBy
element indicates who added the attachment. It could be a user, not a group or
a list of users or groups.
When an ad-hoc attachment is added to a task, the system
returns an identifier that is unique among any attachment for the task. It is
then possible to retrieve or delete the attachment by the attachment
identifier.
Attachment
Info Data Type
The following data type is used to return attachment
information on ad-hoc attachments.
<xsd:element name="attachmentInfo" type="tAttachmentInfo" />
<xsd:complexType name="tAttachmentInfo">
<xsd:sequence>
<xsd:element name="identifier" type="xsd:anyURI" />
<xsd:element name="name" type="xsd:string" />
<xsd:element name="accessType" type="xsd:string" />
<xsd:element name="contentType" type="xsd:string" />
<xsd:element name="contentCategory" type="xsd:anyURI" />
<xsd:element name="attachedTime" type="xsd:dateTime" />
<xsd:element name="attachedBy" type="htt:tUser" />
<xsd:any namespace="##other"
processContents="lax"
minOccurs="0" maxOccurs="unbounded"
/>
</xsd:sequence>
</xsd:complexType>
Attachment
Data Type
The following data type is used to return ad-hoc
attachments.
<xsd:element name="attachment" type="tAttachment" />
<xsd:complexType name="tAttachment">
<xsd:sequence>
<xsd:element ref="attachmentInfo" />
<xsd:element name="value" type="xsd:anyType" />
</xsd:sequence>
</xsd:complexType>
3.8.3.2 Comments
A WS-HumanTask Processor MAY allow tasks to have associated
textual notes added by participants of the task. These notes are collectively
referred to as task comments. Comments are essentially a chronologically
ordered list of notes added by various users who worked on the task. A comment
has an ID, comment text, the user and timestamp for creation and the user and
timestamp of the last modification. Comments are added, modified or deleted individually,
but are retrieved as one group. Comments usage is optional in a task.
The addedTime
element indicates when the comment is added.
The addedBy
element indicates who added the comment. It could be a user, not a group or a
list of users or groups.
The lastModifiedTime
element indicates when the comment was last modified.
The lastModifiedBy
element indicates who last modified the comment.
Comment
Data Type
The following data type is used to return comments.
<xsd:element name="comment" type="tComment" />
<xsd:complexType name="tComment">
<xsd:sequence>
<xsd:element name="id" type="xsd:stringanyURI"
/>
<xsd:element name="addedTime" type="xsd:dateTime" />
<xsd:element name="addedBy" type="htt:tUser" />
<xsd:element name="lastModifiedTime" type="xsd:dateTime" />
<xsd:element name="lastModifiedBy" type="htdhtt:tUser"
/>
<xsd:element name="text" type="xsd:string" />
<xsd:any namespace="##other"
processContents="lax"
minOccurs="0" maxOccurs="unbounded"
/>
</xsd:sequence>
</xsd:complexType>
Comments can be added to a task and retrieved from a task.
The following data types are used to represent instance data
of a task or a notification. The data type htt:tTaskAbstract is used to provide the summary data
of a task or a notification that is displayed on a task list. The data type htt:tTaskDetails contains the
data of a task or a notification, except ad-hoc attachments, comments and
presentation description. The data that is not contained in htt:tTaskDetails can be retrieved
separately using the task API.
Contained presentation elements are in a single language
(the context determines that language, e.g., when a task abstract is returned
in response to a simple query, the language from the locale of the requestor is
used).
The elements startByExists
and completeByExists have a
value of “true” if the task has at least one start deadline or at least one
completion deadline respectively. The actual times (startByTime and completeByTime)
of the individual deadlines can be retrieved using the query operation (see
section 7.1.3 “Advanced Query Operation”).
Note that elements that do not apply to notifications are
defined as optional.
TaskAbstract
Data Type
<xsd:element name="taskAbstract" type="tTaskAbstract" />
<xsd:complexType name="tTaskAbstract">
<xsd:sequence>
<xsd:element name="id"
type="xsd:stringanyURI"
/>
<xsd:element name="taskType"
type="xsd:string" />
<xsd:element name="name"
type="xsd:QName" />
<xsd:element name="status"
type="tStatus" />
<xsd:element name="priority"
type="tPriority" minOccurs="0" />
<xsd:element name="createdTime"
type="xsd:dateTime" />
<xsd:element name="activationTime"
type="xsd:dateTime" minOccurs="0" />
<xsd:element name="expirationTime"
type="xsd:dateTime" minOccurs="0" />
<xsd:element name="isSkipable"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="hasPotentialOwners"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="startByTimeExists"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="completeByTimeExists"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="presentationName"
type="tPresentationName" minOccurs="0" />
<xsd:element name="presentationSubject"
type="tPresentationSubject" minOccurs="0" />
<xsd:element name="renderingMethodExists"
type="xsd:boolean" />
<xsd:element name="hasOutput"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="hasFault"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="hasAttachments"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="hasComments"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="escalated"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="outcome"
type="xsd:string" minOccurs="0"/>
<xsd:element name="parentTaskId"
type="xsd:stringanyURI"
minOccurs="0"/>
<xsd:element name="hasSubTasks"
type="xsd:boolean" minOccurs="0"/>
<xsd:any namespace="##other"
processContents="lax"
minOccurs="0" maxOccurs="unbounded"
/>
</xsd:sequence>
</xsd:complexType>
TaskDetails
Data Type
<xsd:element name="taskDetails" type="tTaskDetails"/>
<xsd:complexType name="tTaskDetails">
<xsd:sequence>
<xsd:element name="id"
type="xsd:stringanyURI"/>
<xsd:element name="taskType"
type="xsd:string"/>
<xsd:element name="name"
type="xsd:QName"/>
<xsd:element name="status"
type="tStatus"/>
<xsd:element name="priority"
type="htt:tPriority" minOccurs="0"/>
<xsd:element name="taskInitiator"
type="htt:tUser" minOccurs="0"/>
<xsd:element name="taskStakeholders"
type="htt:tOrganizationalEntity" minOccurs="0"/>
<xsd:element name="potentialOwners"
type="htt:tOrganizationalEntity" minOccurs="0"/>
<xsd:element name="businessAdministrators"
type="htt:tOrganizationalEntity" minOccurs="0"/>
<xsd:element name="actualOwner"
type="htt:tUser" minOccurs="0"/>
<xsd:element name="notificationRecipients"
type="htt:tOrganizationalEntity" minOccurs="0"/>
<xsd:element name="createdTime"
type="xsd:dateTime"/>
<xsd:element name="createdBy"
type="xsd:string" minOccurs="0"/>
<xsd:element name="lastModifiedTime"
type="xsd:dateTime"/>
<xsd:element name="lastModifiedBy"
type="xsd:string" minOccurs="0"/>
<xsd:element name="activationTime"
type="xsd:dateTime" minOccurs="0"/>
<xsd:element name="expirationTime"
type="xsd:dateTime" minOccurs="0"/>
<xsd:element name="isSkipable"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="hasPotentialOwners"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="startByTimeExists"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="completeByTimeExists"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="presentationName"
type="tPresentationName" minOccurs="0"/>
<xsd:element name="presentationSubject"
type="tPresentationSubject" minOccurs="0"/>
<xsd:element name="renderingMethodExists"
type="xsd:boolean"/>
<xsd:element name="hasOutput"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="hasFault"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="hasAttachments"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="hasComments"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="escalated"
type="xsd:boolean" minOccurs="0"/>
<xsd:element name="searchBy"
type="xsd:string" minOccurs="0"/>
<xsd:element name="outcome"
type="xsd:string" minOccurs="0"/>
<xsd:element name="parentTaskId"
type="xsd:stringanyURI"
minOccurs="0"/>
<xsd:element name="hasSubTasks"
type="xsd:boolean" minOccurs="0”/>
<xsd:any namespace="##other"
processContents="lax"
minOccurs="0" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
Common
Data Types
<xsd:simpleType name="tPresentationName">
<xsd:annotation>
<xsd:documentation>length-restricted string</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:maxLength value="64"
/>
<xsd:whiteSpace value="preserve"
/>
</xsd:restriction>
</xsd:simpleType>
<xsd:simpleType name="tPresentationSubject">
<xsd:annotation>
<xsd:documentation>length-restricted string</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:maxLength value="254"
/>
<xsd:whiteSpace value="preserve"
/>
</xsd:restriction>
</xsd:simpleType>
<xsd:simpleType name="tStatus">
<xsd:restriction base="xsd:string" />
</xsd:simpleType>
<xsd:simpleType name="tPredefinedStatus">
<xsd:annotation>
<xsd:documentation>for documentation
only</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:enumeration value="CREATED"
/>
<xsd:enumeration value="READY"
/>
<xsd:enumeration value="RESERVED"
/>
<xsd:enumeration value="IN_PROGRESS"
/>
<xsd:enumeration value="SUSPENDED"
/>
<xsd:enumeration value="COMPLETED"
/>
<xsd:enumeration value="FAILED"
/>
<xsd:enumeration value="ERROR"
/>
<xsd:enumeration value="EXITED"
/>
<xsd:enumeration value="OBSOLETE"
/>
</xsd:restriction>
</xsd:simpleType>
To support sub tasks the task instance data gets enhanced
by the following (optional) parameters:
·
sub tasks à A
list of task identifiers for each already-created subtask of the task,
including both non-terminated and terminated instances
à A list of the names of the sub tasks available
for creation in the definition of the task, based on the composition type,
instantiation pattern, and already created tasks
·
parent task à
The identifier of the superior composite task of this task if it is a sub task
The <task>
element is used to specify human tasks. This section introduces the syntax for
the element, and individual properties are explained in subsequent sections.
Definition of human tasks:
<htd:task name="NCName" actualOwnerRequired="yes|no"?>
<htd:interface portType="QName"
operation="NCName"
responsePortType="QName"? responseOperation="NCName"? />
<htd:priority expressionLanguage="anyURI"? >?
integer-expression
</htd:priority>
<htd:peopleAssignments>?
...
</htd:peopleAssignments>
<htd:completionBehavior>?
...
</htd:completionBehavior>
<htd:delegation
potentialDelegatees="anybody|nobody|potentialOwners|other" />?
<htd:from>?
...
</htd:from>
</htd:delegation>
<htd:presentationElements>?
...
</htd:presentationElements>
<htd:possibleOutcomes>?
...
</htd:possibleOutcomes>
<htd:outcome part="NCName" queryLanguage="anyURI">?
queryContent
</htd:outcome>
<htd:searchBy expressionLanguage="anyURI"? >?
expression
</htd:searchBy>
<htd:renderings>?
<htd:rendering type="QName">+
...
</htd:rendering>
</htd:renderings>
<htd:deadlines>?
<htd:startDeadline name="NCName">*
...
</htd:startDeadline>
<htd:completionDeadline name="NCName">*
...
</htd:completionDeadline>
</htd:deadlines>
<htd:composition>?
...
</htd:composition>
</htd:task>
The following attributes and elements are defined for tasks:
·
name: This
attribute is used to specify the name of the task. The name combined with the
target namespace MUST uniquely identify a task element enclosed in the task
definition. This attribute is mandatory. It is not used for task rendering.
·
actualOwnerRequired: This optional attribute
specifies if an actual owner is required for the task. Setting the value to "no" is used for composite tasks
where subtasks should be activated automatically without user interaction. For
routing tasks his attribute MUST be set to "no".
Tasks that have been defined to not have subtasks MUST have exactly one actual
owner after they have been claimed. For these tasks the value of the attribute
value MUST be "yes". The default value for the
attribute is "yes".
·
interface: This
element is used to specify the operation used to invoke the task. The operation
is specified using WSDL, that is, a WSDL port type and WSDL operation are
defined. The element and its portType
and operation attributes MUST be
present for normal tasks. The schema only marks it optional so that Lean Tasks
can make it prohibited. The interface is specified in one of the following
forms:
§
The WSDL operation is a one-way operation and the task
asynchronously returns output data. In this case, a WS-HumanTask Definition
MUST specify a callback one-way operation, using the responsePortType and responseOperation
attributes. This callback operation is invoked when the task has finished. The
Web service endpoint address of the callback operation is provided at runtime
when the task’s one-way operation is invoked (for details, see section 10 ”Providing Callback Information for Human Tasks”).
§
The WSDL operation is a request-response operation. In
this case, the responsePortType
and responseOperation attributes
MUST NOT be specified.
·
priority: This
element is used to specify the priority of the task. It is an optional element
which value is an integer expression. If present, the WS-HumanTask Definition
MUST specify a value between 0 and 10, where 0 is the highest priority and 10
is the lowest. If not present, the priority of the task is considered as 5. The
result of the expression evaluation is of type htt:tPriority.
The expressionLanguage attribute
specifies the language used in the expression. The attribute is optional. If
not specified, the default language as inherited from the closest enclosing
element that specifies the attribute is used.
·
peopleAssignments:
This element is used to specify people assigned to different generic human
roles, i.e. potential owners, and business administrator. The element is optional.
See section 3.5 for more details on people assignments.
·
completionBehavior:
This element is used to specify completion conditions of the task. It is
optional. See section 4.8 for more details on completion behavior.
·
delegation: This
element is used to specify constraints concerning delegation of the task.
Attribute potentialDelegatees
defines to whom the task can be delegated. One of the following values MUST be
specified:
§
anybody: It is
allowed to delegate the task to anybody
§
potentialOwners:
It is allowed to delegate the task to potential owners previously selected
§
other: It is
allowed to delegate the task to other people, e.g. authorized owners. The
element <from> is used to
determine the people to whom the task can be delegated.
§
nobody: It is not
allowed to delegate the task.
The delegation element is optional.
If this element is not present the task is allowed to be delegated to anybody.
·
presentationElements:
This element is used to specify different information used to display the task
in a task list, such as name, subject and description. See section 4.3 for more details on presentation elements. The element is optional.
·
outcome: This
optional element identifies the field (of an xsd simple type) in the output
message which reflects the business result of the task. A conversion takes
place to yield an outcome of type
xsd:string. The optional attribute queryLanguage
specifies the language used for selection. If not specified, the default
language as inherited from the closest enclosing element that specifies the
attribute is used.
·
searchBy: This
optional element is used to search for task instances based on a custom search
criterion. The result of the expression evaluation is of type xsd:string. The expressionLanguage attribute specifies
the language used in the expression. The attribute is optional. If not
specified, the default language as inherited from the closest enclosing element
that specifies the attribute is used.
·
rendering: This
element is used to specify the rendering method. It is optional. If not
present, task rendering is implementation dependent. See section 4.4 for more details on rendering tasks.
·
deadlines: This
element specifies different deadlines. It is optional. See section 4.9 for more details on timeouts and escalations.
·
composition: This
element is used to specify subtasks of a composite task. It is optional. See
section 4.6 for more details on composite tasks.
Information about human tasks or notifications needs to be
made available in a human-readable way to allow users dealing with their tasks
and notifications via a user interface, which could be based on various
technologies, such as Web browsers, Java clients, Flex-based clients or .NET
clients. For example, a user queries for her tasks, getting a list of tasks she
could work on, displaying a short description of each task. Upon selection of
one of the tasks, more complete information about the task is displayed by the
user interface.
Alternatively, a task or notification could be sent directly
to a user’s inbox, in which case the same information would be used to provide
a human readable rendering there.
The same human readable information could also be used in
reports on all the human tasks executed by a particular human task management
system.
Human readable information can be specified in multiple
languages.
Syntax:
<htd:presentationElements>
<htd:name xml:lang="xsd:language"? >*
Text
</htd:name>
<!-- For the subject and description only,
replacement variables can
be used. -->
<htd:presentationParameters expressionLanguage="anyURI"? >?
<htd:presentationParameter name="NCName" type="QName">+
expression
</htd:presentationParameter>
</htd:presentationParameters>
<htd:subject xml:lang="xsd:language"? >*
Text
</htd:subject>
<htd:description xml:lang="xsd:language"?
contentType="mimeTypeString"? >*
<xsd:any minOccurs="0"
maxOccurs="unbounded" />
</htd:description>
</htd:presentationElements>
Properties
The following attributes and elements are defined for the htd:presentationElements
element.
- name:
This element is the short title of a task. It uses xml:lang, a standard XML attribute,
to define the language of the enclosed information. This attribute uses
tags according to RFC 1766 (see [RFC1766]). There could be zero or more name elements. A
WS-HumanTask Definition MUST NOT specify multiple name elements having the same value
for attribute xml:lang.
- presentationParameters:
This element specifies parameters used in presentation elements subject and description. Attribute
expressionLanguage
identifies the expression language used to define parameters. This
attribute is optional. If not specified, the default language as inherited
from the closest enclosing element that specifies the attribute is used.
Element presentationParameters
is optional and if present then the WS-HumanTask Definition MUST
specify at least one element presentationParameter. Element presentationParameter has
attribute name,
which uniquely identifies the parameter definition within the presentationParameters element,
and attribute type
which defines its type. A WS-HumanTask Definition MUST specify parameters
of XSD simple types. When a presentationParameter is used within subject and description, the
syntax is {$parameterName}.
The pair "{{"
represents the character "{" and the pair "}}"
represents the character "}". Only the defined presentation
parameters are allowed, that is, a WS-HumanTask Definition MUST NOT
specify arbitrary expressions embedded in this syntax.
- subject:
This element is a longer text that describes the task. It uses xml:lang to
define the language of the enclosed information. There could be zero or
more subject
elements. A WS-HumanTask Definition MUST NOT specify multiple subject elements
having the same value for attribute xml:lang.
- description:
This element is a long description of the task. It uses xml:lang to
define the language of the enclosed information. The optional attribute contentType uses
content types according to RFC 2046 (see [RFC 2046]). The default value
for this attribute is “text/plain”. A WS-HumanTask Processor MUST support
the content type “text/plain”. The WS-HumanTask Processor SHOULD support
HTML (such as “text/html” or “application/xml+xhtml”). There could be zero
or more description
elements. As descriptions can exist with different content types, it is
allowed to specify multiple description elements having the same value for
attribute xml:lang,
but the WS-HumanTask Definition MUST specify different content types.
Example:
<htd:presentationElements>
<htd:name xml:lang="en-US">Approve Claim</htd:name>
<htd:name xml:lang="de-DE">
Genehmigung der
Schadensforderung
</htd:name>
<htd:presentationParameters>
<htd:presentationParameter name="firstname" type="xsd:string">
htd:getInput("ClaimApprovalRequest")/cust/firstname
</htd:presentationParameter>
<htd:presentationParameter name="lastname" type="xsd:string">
htd:getInput("ClaimApprovalRequest")/cust/lastname
</htd:presentationParameter>
<htd:presentationParameter name="euroAmount" type="xsd:double">
htd:getInput("ClaimApprovalRequest")/amount
</htd:presentationParameter>
</htd:presentationParameters>
<htd:subject xml:lang="en-US">
Approve the insurance claim
for €{$euroAmount} on behalf of
{$firstname} {$lastname}
</htd:subject>
<htd:subject xml:lang="de-DE">
Genehmigung der Schadensforderung
über €{$euroAmount} für
{$firstname} {$lastname}
</htd:subject>
<htd:description xml:lang="en-US"
contentType="text/plain">
Approve this claim following
corporate guideline #4711.0815/7 ...
</htd:description>
<htd:description xml:lang="en-US"
contentType="text/html">
<p>
Approve this claim
following corporate guideline
<b>#4711.0815/7</b>
...
</p>
</htd:description>
<htd:description xml:lang="de-DE" contentType="text/plain">
Genehmigen Sie diese
Schadensforderung entsprechend Richtlinie Nr.
4711.0815/7 ...
</htd:description>
<htd:description xml:lang="de-DE" contentType="text/html">
<p>
Genehmigen Sie
diese Schadensforderung entsprechend Richtlinie
<b>Nr.
4711.0815/7</b>
...
</p>
</htd:description>
</htd:presentationElements>
The <possibleOutcomes>
element provides a way for a task to define which values are usable for the
outcome value of a task. Having a separate definition allows a tool for
building tasks to provide support that understands exactly which outcomes are
possible for a particular task.
<htd:possibleOutcomes>
<htd:possibleOutcome name="NCName">+
<htd:outcomeName xml:lang="xsd:language"?>+
Language specific display
</htd:outcomeName>
</htd:possibleOutcome>
</htd:possibleOutcomes>
Each <possibleOutcome>
element represents one possible outcome. For the typical example of an expense
report approval, the two outcomes might be ‘Approve’ and ‘Reject’. In addition
to the other data being collected by the rendering in the WS-HumanTask Client,
this represents the most important information about how to proceed in a
process that contains multiple tasks. Therefore, a rendering and client using
HTML might choose to show this as a dropdown list, list box with single
selection, a set of submit buttons, or a radio button group.
For each <possibleOutcome>, it is possible to have an <outcomeName>
element to specify a per-language display name. It uses xml:lang, a standard XML attribute, to
define the language of the enclosed information. This attribute uses tags according
to RFC 1766 (see [RFC1766]). There could be zero or more <outcomeName>
elements. A <possibleOutcome>
MUST NOT specify multiple <outcomeName> elements having the same value for attribute xml:lang.
Human tasks and notifications need to be rendered on user
interfaces like forms clients, portlets, e-mail clients, etc. The rendering
element provides an extensible mechanism for specifying UI renderings for human
tasks and notifications (task-UI). The element is optional. One or more
rendering methods can be provided in a task definition or a notification
definition. A task or notification can be deployed on any WS-HumanTask
Processor, irrespective of the fact whether the implementation supports
specified rendering methods or not. The rendering method is identified using a
QName.
Unlike for presentation elements, language considerations
are opaque for the rendering element because the rendering applications
typically provide multi-language support. Where this is not the case, providers
of certain rendering types can decide to extend the rendering method in order
to provide language information for a given rendering.
The content of the rendering element is not defined by this
specification. For example, when used in the rendering element, XPath extension
functions as defined in section 7.2 MAY be evaluated by a WS-HumanTask
Processor.
Syntax:
<htd:renderings>
<htd:rendering type="QName">+
<xsd:any minOccurs="1"
maxOccurs="1" />
</htd:rendering>
</htd:renderings>
A composite task is defined as a <htd:task> element with the <htd:composition>
element enclosed in it. The following are attributes and elements defined for
the composition
element.
·
type:
This optional attribute specifies the order in which enclosed sub-tasks are
executed. If the value is set to “sequential” the sub-tasks MUST be executed in
lexical order. Otherwise they MUST be executed in parallel. The default value
for this attribute is “sequential”.
·
instantiationPattern:
This optional attribute specifies the way how sub-tasks are instantiated. If
the value is set to “manual” the task client triggers instantiation of enclosed
sub-tasks. Otherwise, they are automatically instantiated at the time the composite
task itself turns into status “inProgress”. The default value for this
attribute is “manual”.
·
subtask: This element specifies a task that
will be executed as part of the composite task execution. The composition element
MUST enclose at least one subtask element. The subtask element has the following attributes and
elements. The name
attribute specifies the name of the sub-task. The name MUST be unique among the
names of all sub-tasks within the composition element. The htd:task element is used to define the
task inline. The htd:localTask
element is used to reference a task that will be executed as a sub-task. The htd:localTask element
MAY define values for standard overriding attributes: priority and people
assignments. The toParts element is used to assign values to
input message of the sub-task. The enclosed XPath expression MAY refer to the
input message of the composite task or the output message of other sub-task
enclosed in the same composition
element. The part
attribute refers to a part of the WSDL message type of the message used in the
XPath. The expressionLanguage
attribute specifies the expression language used in the enclosing elements. The
default value for this attribute is urn:ws-ht:sublang:xpath1.0 which represents the usage of
XPath 1.0 within human interactions definition. A WS-HumanTask Definition that
uses expressions MAY override the default expression language for individual
expressions.
When composition is defined on a task, the composition MUST
be applied for each of the potential owners defined in the task's people
assignment.
Syntax:
<htd:task>
...
<htd:composition type="sequential|parallel"
instantiationPattern="manual|automatic">
<htd:subtask name="NCName">+
( <htd:task>
...
</htd:task>
| <htd:localTask
reference="QName">
standard-overriding-elements
...
</htd:localTask>
)
<htd:toParts>?
<htd:toPart part="NCName" expressionLanguage="anyURI">+
XPath expression
</htd:toPart>
</htd:toParts>
</htd:subtask>
</htd:composition>
...
</htd:task>
Standard-overriding-elements is used in the syntax
above as a shortened form of the following list of elements:
<htd:priority expressionLanguage="anyURI"? >
integer-expression
</htd:priority>
<htd:peopleAssignments>?
<htd:genericHumanRole>
<htd:from>...</htd:from>
</htd:genericHumanRole>
</htd:peopleAssignments>
The <peopleAssignments>
element is used to assign people to a task. For each generic human role, a
people assignment element can be specified. A WS-HumanTask Definition MUST
specify a people assignment for potential owners of a human task. An empty <potentialOwners> element is used to specify that no
potential owner is assigned by the human task's definition but another means is
used e.g. nomination. Specifying people assignments for task stakeholders, task
initiators, excluded owners and business administrators is optional. Human
tasks never specify recipients. A WS-HumanTask Definition MUST NOT specify
people assignments for actual owners.
Syntax:
<htd:peopleAssignments>
<htd:potentialOwners>
...
</htd:potentialOwners>
<htd:excludedOwners>?
...
</htd:excludedOwners>
<htd:taskInitiator>?
...
</htd:taskInitiator>
<htd:taskStakeholders>?
...
</htd:taskStakeholders>
<htd:businessAdministrators>?
...
</htd:businessAdministrators>
</htd:peopleAssignments>
People assignments can result in a set of values or an empty
set. In case people assignment results in an empty set then the task
potentially requires administrative attention. This is out of scope of the
specification, except for people assignments for potential owners (see section 4.10.1 “Normal processing of a Human Task” for more details).
Example:
<htd:peopleAssignments>
<htd:potentialOwners>
<htd:from logicalPeopleGroup="regionalClerks">
<htd:argument name="region">
htd:getInput("ClaimApprovalRequest")/region
</htd:argument>
</htd:from>
</htd:potentialOwners>
<htd:businessAdministrators>
<htd:from logicalPeopleGroup="regionalManager">
<htd:argument name="region">
htd:getInput("ClaimApprovalRequest")/region
</htd:argument>
</htd:from>
</htd:businessAdministrators>
</htd:peopleAssignments>
Tasks can be assigned to people in sequence and parallel.
Elements htd:sequence
and htd:parallel
elements in htd:potentialOwners are used to represent such assignments.
4.7.1.1 Parallel Pattern
A task can be assigned to people in parallel using the htd:parallel element.
. The htd:parallel
element is defined as follows:
·
The htd:from
element defines the parallel potential owners. This can evaluate to multiple
users/groups.
·
The attribute ‘type’ in htd:parallel identifies how parallel assignments are
created for the multiple users/groups returned from htd:from. If type is ‘all’ then an
assignment MUST be created for each user returned by htd:from. If type is ‘single’ then an
assignment MUST be created for each htd:from clause (this assignment could have with n
potential owners). The default value of type is ‘all’.
·
The htd:parallel
and htd:sequence
elements define nested routing patterns within the parallel routing pattern
·
The htd:completionBehavior
defines when the routing pattern completes. The completion criteria also define
how the result is constructed for the parent task when a parallel routing
pattern is complete.
Each parallel assignment MUST result in a separate sub task.
Sub tasks created for each parallel assignment MUST identify the parent task
using the htd:parentTaskId.
Syntax:
<htd:potentialOwners>
<htd:parallel type="all|single"?>
<htd:completionBehavior>
<htd:from>...</htd:from>*
pattern*
</htd:parallel>
</htd:potentialOwners>
Example:
<htd:peopleAssignments>
<htd:potentialOwners>
<htd:parallel type="all">
<htd:from>
htd:getInput("ClaimApprovalRequest")/claimAgent
</htd:from>
</htd:parallel>
</htd:potentialOwners>
</htd:peopleAssignments>
4.7.1.2 Sequential Pattern
A task can be assigned to people in sequence using the htd:sequence element.
The htd:sequence
is defined as follows:
- The htd:from element can evaluate to multiple users/groups.
- The attribute ‘type’ in htd:sequence identifies how sequential
assignments are created for the multiple users/groups returned from htd:from. If
type is ‘all’ an assignment MUST be created for each user returned by htd:from. If
type is ‘single’, an assignment MUST be created for each htd:from clause
(this assignment could have with n potential owners). The default value of
type is ‘all’.
- The htd:parallel and htd:sequence elements define nested routing
patterns within the sequential routing pattern.
- The htd:completionBehavior defines when the routing pattern
completes. The completion criteria also define how the result is
constructed for the parent task when a sequential routing pattern is
complete.
Sequential routing patterns MUST use a separate sub task for
each step in a sequential pattern. Sub tasks created for each sequential
assignment MUST identify the parent task using the htd:parentTaskId.
Syntax:
<htd:potentialOwners>
<htd:sequence type="all|single"?>
<htd:completionBehavior>?
<htd:from>...</htd:from>*
pattern*
</htd:sequence>
</htd:potentialOwners>
Example:
<htd:peopleAssignments>
<htd:potentialOwners>
<htd:sequence type="all">
<htd:from logicalPeopleGroup="regionalClerks">
<htd:argument name="region">
htd:getInput("ClaimApprovalRequest")/region
</htd:argument>
</htd:from>
<htd:from
logicalPeopleGroup="regionalManager">
<htd:argument name="region">
htd:getInput("ClaimApprovalRequest")/region
</htd:argument>
</htd:from>
</htd:sequence>
</htd:potentialOwners>
</htd:peopleAssignments/>
The completion behavior of a task, routing pattern or
composite task can be influenced by a specification of completion conditions and
the result construction for tasks, routing patterns, or composite tasks. For
this purpose, the task, routing pattern or composite task contains a htd:completionBehavior element.
Multiple completion conditions can be specified as nested htd:completion elements. They are
evaluated in lexical order. When one of the specified completion conditions is
met then the task is considered to be completed; in case of routing patterns
and composite tasks all remaining running sub tasks MUST be skipped (i.e., set
to the "Obsolete" state) and the associated result construction MUST
be applied.
In case of composite tasks and routing patterns the
following applies: At most one default completion MUST be specified with no
completion condition in order to specify the result construction after regular
completion of all sub tasks. If no result construction is applied, e.g. because
no “default” result construction is specified and none of the specified
completion conditions is met, then the parent task’s output is not created,
i.e., it remains uninitialized. Moreover, note that a completion condition can
be specified without referencing sub task output data, which allows the parent
task to be considered completed even without creating any sub tasks. When
output data from sub tasks is referenced by completion conditions or result
constructions, only output data of already finished sub tasks MUST be
considered.
If none of the specified completion conditions is met then
the state of the task or the parent task remains unchanged.
<htd:completionBehavior completionAction=”manual|automatic”?>?
<htd:completion name="NCName">*
<htd:condition ... >
...
</htd:condition>
<htd:result>?
...
<htd:result>
</htd:completion>
<htd:defaultCompletion>?
<htd:result>
...
<htd:result>
</htd:defaultCompletion>
</htd:completionBehavior>
The completionBehavior
element has optional attribute completionAction. This optional attribute specifies how the task, routing
pattern, or composite task is completed. If the value is set to
"manual" the task or parent task MUST be completed explicitly by the
actual owner as soon as the completion conditions evaluate to true. If the
value is set to "automatic" the task or parent task MUST be set to
complete as soon as the completion conditions evaluate to true. For routing
patterns, the completionAction attribute MUST have value "automatic". The
default value for this attribute is “automatic”.
If completionBehavior is not
specified, the default behavior is that of a completionBehavior
with completionCondition is "true" and a completionAction of
"manual" for simple and composite tasks, and "automatic" for
routing patterns.
A completion condition defines when a task or a set of sub
tasks associated with the parent task is considered completed. It is specified
Boolean expression which can refer to input data of the task, the parent task
or its sub tasks, output data produced by already finished sub tasks, or other
data obtained from WS-HumanTask API calls (e.g. the number of sub tasks), or
functions that test that some designated amount of time has passed.
The completion condition MUST be defined using an htd:condition element.
<htd:condition expressionLanguage="anyURI"?>
boolean expression
</htd:condition>
Within the Boolean expression of a completion condition, aggregation functions can be used to evaluate output data
produced by the already finished sub tasks of the parent task.
If an error (e.g. division by zero) occurs during the
condition evaluation then the condition MUST be considered to have evaluated to
“false”.
The time functions that are available are defined as
follows:
- boolean
htd:waitFor(string)
- The parameter is an XPath expression evaluating to a
string conforming to the definition of the XML Schema type duration
- The return value is true
after the specified duration has elapsed, otherwise false
- boolean
htd:waitUntil(string)
- The parameter is an XPath expression evaluating to a
string conforming to the definition of the XML Schema type dateTime
The return value is true
after the specified absolute time has passed, otherwise false.
Completion conditions of a task MUST use only time
functions.
4.8.1.1 Evaluating the Completion Condition
The time functions in the completion condition are be
evaluated with respect to the beginning of execution of the task or parent task
on which the completion is defined. To achieve this, the evaluation of the htd:waitFor and htd:waitUntil calls within the
condition are treated differently from the rest of the expression. When the
containing task or parent task is created, the actual parameter expression for
any htd:waitFor and htd:waitUntil calls MUST be evaluated
and the completion condition should be rewritten to replace these calls with
only htd:waitUntil calls with
constant parameters. The durations calculated for any htd:waitFor calls MUST be converted into absolute times
and rewritten as htd:waitUntil calls.
The result of these replacements is called the preprocessed completion
condition.
For the parent task, the preprocessed completion condition
MUST be evaluated at the following times:
- Before starting the first subtask (it may be complete
before it starts)
- Whenever a subtask completes
- Whenever a duration specified in a htd:waitFor call has elapsed
- Whenever an absolute time specified in a htd:waitUntil call is passed.
For tasks, the preprocessed completion condition MUST be
evaluated at the following times:
- Before starting the task (it may be complete before it
starts)
- Whenever a duration specified in a htd:waitFor call has elapsed
- Whenever an absolute time specified in a htd:waitUntil call is passed.
Example:
The first completion condition may be met even without
starting sub tasks. When both parts of the second completion condition are met,
that is, 7 days have expired and more than half of the finished sub tasks have
an outcome of “Rejected”, then the parallel routing pattern is considered
completed.
<htd:parallel>
...
<htd:completionBehavior>
<htd:completion>
<htd:condition>
htd:getInput("ClaimApprovalRequest")/amount < 1000
</htd:condition>
<htd:result> ... </htd:result>
</htd:completion>
<htd:completion>
<htd:condition>
(
htd:getCountOfSubtasksWithOutcome("Rejected") /
htd:getCountOfSubtasks() > 0.5 )
and htd:waitFor("P7D")
</htd:condition>
<htd:result> ... </htd:result>
</htd:completion>
</htd:completionBehavior>
...
</htd:parallel>
When multiple sub tasks are created in order let several
people work on their own sub task in parallel then the outputs of these sub
tasks sometimes need to be combined for the creation of the
parent task’s output.
If all sub tasks have the same interface
definition (as in routing patterns) then the result construction can be defined
in a declarative way using aggregation functions. Alternatively, the result may
be created using explicit assignments.
The result construction MUST be defined as htd:result element, containing one or
more htd:aggregate or htd:copy elements, executed in the
order in which they appear in the task definition.
<htd:result>
(
<htd:aggregate ... />
|
<htd:copy> ...
</htd:copy>
)+
</htd:result>
4.8.2.1 Declarative Result Aggregation
An htd:aggregate
element describes the result aggregation for a leaf element of the parent
task’s output document. In most cases, this approach is only meaningful for
routing patterns with identical sub task interfaces. Note that the construction
of (complex-typed) non-leaf elements is out of scope of the declarative result
aggregation.
<htd:aggregate part="NCName"?
location="query"?
condition="bool-expr"?
function="function-call"/>+
The htd:aggregate
element is defined as follows:
- The optional part
attribute MUST contain the name of a WSDL part. The part attribute MUST be
specified when the task interface is defined using a WSDL message with
more than one WSDL part.
- The optional location
attribute MUST contain a query pointing to the location of a leaf element
of the tasks’ output documents:
- For each parallel sub task, this is the location of
exactly one element of the sub task’s output document that is processed
by the aggregation function. Each sub tasks’ output element is
(conditionally) added to a node-set passed as parameter to the aggregation
function.
- For the parent task, this is the element created in the
task’s output document that is the computed return value of the
aggregation function.
- The optional condition
attribute MUST contain a Boolean expression evaluated on each sub task’s output
document. If the expression evaluates to true
then the sub task’s output element identified by location is added to the node-set passed to the
aggregation function.
- The mandatory function
attribute contains the name of the aggregation function (QName; see a list
of supported aggregation functions below) and optional arguments, in the
following form:
FunctionName '(' ( Argument
( ',' Argument )* )? ')'
Important:
- The first parameter of each aggregation function is the
node-set of sub task’s output elements to be aggregated. This parameter
is inserted implicitly and MUST NOT be specified within the function attribute.
- Within the function
attribute, function arguments MUST be specified only for additional
parameters defined for an aggregation function.
If a declarative result aggregation is applied, it
is still possible that no values can be provided for the aggregation of a
particular output field, for example, if no subtask has set a value to an
optional field (by omission or by an explicit nil value).
In this case, the following rules determine how the
aggregated output field of the parent task is set.
- Rule (1): If the result value is optional
(element defined with minOccurs="0"
or attribute defined with use="optional")
then the corresponding element or attribute in the parent task output MUST
be omitted.
- Rule (2): If rule (1) does not apply and a
default value is provided (element or attribute defined with default="{value}")
then the parent task output element or attribute MUST be explicitly set to
this default value.
- Rule (3): If rules (1)-(2) do not apply and
the result value is a nillable element (element defined with nillable="true")
then the parent task output element MUST be set to a nil value (<a
xsi:nil="true"/>).
- Rule (4): If rules (1)-(3) do not apply, that
is, the result is mandatory (element defined with minOccurs="1"
or attribute defined with use="required")
but a value cannot be supplied, then a standard fault htd:aggregationFailure
MUST be thrown to indicate a non-recoverable error.
Example:
Consider the following output document used in a parallel
routing pattern:
<element name="Award" type="tns:tAward"
/>
<complexType name="tAward">
<sequence>
<element name="AwardRecommended" type="xsd:string" />
<element name="AwardDetails" type="tns:tAwardDetails" />
</sequence>
</complexType>
<complexType name="tAwardDetails">
<sequence>
<element name="Amount" type="xsd:integer"
/>
<element name="Appraisal" type="xsd:string" />
</sequence>
</complexType>
A possible result aggregation could then look like this. The
first aggregation determines the most frequent occurrence of an award
recommendation. The second aggregation calculates the average award amount for
sub tasks with an award recommendation of ‘yes’. The third aggregation creates
a comma-separated concatenation of all sub task’s appraisals.
<htd:parallel ...>
...
<htd:completionBehavior>
<htd:completion>
<htd:condition>
... </htd:condition>
<htd:result>
<htd:aggregate location="/Award/AwardRecommended"
function="htd:mostFrequentOccurence()"/>
<htd:aggregate location="/Award/AwardDetails/Amount"
condition="/Award/AwardRecommended='yes'"
function="htd:avg()"/>
<htd:aggregate location="/Award/AwardDetails/Appraisal"
function="htd:concatWithDelimiter(',')"/>
</htd:result>
</htd:completion>
</htd:completionBehavior>
</htd:parallel>
4.8.2.2 Explicit Result Assignment
An htd:copy element
describes the explicit assignment to an element of the parent task’s output
document.
<htd:copy>+
<htd:from expressionLanguage="anyURI"?>
expression
</htd:from>
<htd:to queryLanguage="anyURI"?>
query
</htd:to>
</htd:copy>
The htd:copy
element is defined as follows:
- The mandatory htd:from
element MUST contain an expression used to calculate the result value. The
expression can make use of WS-HumanTask aggregation functions.
- The mandatory htd:to
element MUST contain a query pointing to the location of an element of the
tasks’ output documents. This is the element created in the task’s output
document.
Example 1:
Consider the following output document used in a parallel
routing pattern:
<element name="Order" type="tns:tOrder"
/>
<complexType name="tOrder">
<sequence>
<element name="Item" type="tns:tItem"
maxOccurs="unbounded"/>
<element name="TotalPrice" type="xsd:integer" />
</sequence>
</complexType>
<complexType name="tItem">
<sequence>
...
</sequence>
</complexType>
A possible result aggregation could then look like this. All
sub task order item lists are concatenated to one parent task order item list.
The total price is calculated using an aggregation function.
<htd:parallel>
...
<htd:completionBehavior>
<htd:completion>
<htd:condition>
... </htd:condition>
<htd:result>
<htd:copy>
<htd:from>
htd:getSubtaskOutputs("orderResponse", "/Order/Item")
</htd:from>
<htd:to>/Order/Item</htd:to>
</htd:copy>
<htd:copy>
<htd:from>
htd:sum(htd:getSubtaskOutputs("orderResponse",
"/Order/TotalPrice"))
</htd:from>
<htd:to>/Order/TotalPrice</htd:to>
</htd:copy>
</htd:result>
</htd:completion>
</htd:completionBehavior>
</htd:parallel>
Example
2:
Output data from heterogeneous sub tasks is assigned into
the parent task’s output. The complete complex-typed sub task output documents
are copied into child elements of the parent task output document.
<htd:task name="bookTrip">
... produces itinerary ...
<htd:composition type="parallel" ...>
<htd:subtask name="bookHotel">
<htd:task>
... produces hotelReservation ...
</htd:task>
</htd:subtask>
<htd:subtask name="bookFlight">
<htd:task>
... produces flightReservation ...
</htd:task>
</htd:subtask>
</htd:composition>
...
<htd:completionBehavior>
<htd:defaultCompletion>
<htd:result>
<htd:copy>
<htd:from>
htd:getSubtaskOutput("bookHotel",
"bookHotelResponse",
"/hotelReservation")
</htd:from>
<htd:to>/itinerary/hotelReservation</htd:to>
</htd:copy>
<htd:copy>
<htd:from>
htd:getSubtaskOutput("bookFlight",
"bookFlightResponse",
"/flightReservation")
</htd:from>
<htd:to>/itinerary/flightReservation</htd:to>
</htd:copy>
</htd:result>
</htd:defaultCompletion>
</htd:completionBehavior>
</htd:task>
Timeouts and escalations allow the specification of a date
or time before which the task or sub task has to reach a specific state. If the
timeout occurs a set of actions is performed as the response. The state of the
task is not changed. Several deadlines are specified which differ in the point
when the timer clock starts and the state which has to be reached with the
given duration or by the given date. They are:
·
Start deadline: Specifies the time until the task has to start,
i.e. it has to reach state InProgress. It is defined as either the period
of time or the point in time until the task has to reach state InProgress.
Since expressions are allowed, durations and deadlines can be calculated at
runtime, which for example enables custom calendar integration. The time starts
to be measured from the time at which the task enters the state Created.
If the task does not reach state InProgress by the deadline an
escalation action or a set of escalation actions is performed. Once the task is
started, the timer becomes obsolete.
·
Completion deadline: Specifies the due time of the task. It is
defined as either the period of time until the task gets due or the point in
time when the task gets due. The time starts to be measured from the time at
which the task enters the state Created. If the task does not reach one
of the final states (Completed, Failed, Error, Exited,
Obsolete) by the deadline an escalation action or a set of escalation
actions is performed.
The element <deadlines> is used to include the definition of
all deadlines within the task definition. It is optional. If present then the
WS-HumanTask Definition MUST specify at least one deadline. Deadlines defined
in ad-hoc sub tasks created at runtime MUST NOT contradict the deadlines of
their parent task. The value of the name attribute MUST be unique for all
deadline specifications within a task definition.
Syntax:
<htd:deadlines>
<htd:startDeadline name="NCName">*
<htd:documentation xml:lang="xsd:language"? >*
text
</htd:documentation>
( <htd:for expressionLanguage="anyURI"? >
duration-expression
</htd:for>
| <htd:until expressionLanguage="anyURI"? >
deadline-expression
</htd:until>
)
<htd:escalation name="NCName">*
...
</htd:escalation>
</htd:startDeadline>
<htd:completionDeadline name="NCName">*
...
</htd:completionDeadline>
</htd:deadlines>
The language used in expressions is specified using the expressionLanguage
attribute. This attribute is optional. If not specified, the default language
as inherited from the closest enclosing element that specifies the attribute is
used.
For all deadlines if a status is not reached within a
certain time then an escalation action, specified using element <escalation>, can be triggered. The <escalation>
element is defined in the section below. When the task reaches a final state (Completed,
Failed, Error, Exited, Obsolete) all deadlines are deleted.
Escalations are triggered if
- The associated point in time is reached, or duration has elapsed,
and
- The associated condition (if any) evaluates to true
Escalations use notifications to inform people about the
status of the task. Optionally, a task might be reassigned to some other person
or group as part of the escalation. Notifications are explained in more detail
in section 6 “Notifications”. For an escalation, a WS-HumanTask Definition MUST
specify exactly one escalation action.
When defining escalations, a notification can be either
referred to, or defined inline.
- A notification defined in the <humanInteractions> root element or
imported from a different namespace can be referenced by specifying its
QName in the reference
attribute of a <localNotification>
element. When referring to a notification, the priority and the people
assignments of the original notification definition MAY be overridden
using the elements <priority>
and <peopleAssignments>
contained in the <localNotification>
element.
- An inlined notification is defined by a <notification> element.
Notifications used in escalations can use the same type of
input data as the surrounding task or sub task, or different type of data. If
the same type of data is used then the input message of the task or sub task is
passed to the notification implicitly. If not, then the <toPart> elements are used to
assign appropriate data to the notification, i.e. to explicitly create a
multi-part WSDL message from the data. The part attribute refers to a part of the WSDL message.
The expressionLanguage attribute
specifies the language used in the expression. The attribute is optional. If
not specified, the default language as inherited from the closest enclosing
element that specifies the attribute is used.
A WS-HumanTask Definition MUST specify a <toPart> element for every part
in the WSDL message definition because parts not explicitly represented by
<toPart> elements would result in uninitialized parts in the target WSDL
message. The order in which parts are specified is not relevant. If multiple <toPart> elements are present, a
WS-HumanTask Processor MUST execute them in an “all or nothing” manner. If any
of the <toPart>s fails, the escalation action will not be performed and
the execution of the task is not affected.
Reassignments are used to replace the potential owners of a
task when an escalation is triggered. The <reassignment> element is used to specify
reassignment. If present then a WS-HumanTask Definition MUST specify potential
owners. A reassignment triggered by a sub task escalation MUST apply to the sub
task only. A reassignment MAY comprise of a complex people assignment using
Routing Patterns.
In the case where several reassignment escalations are
triggered, the first reassignment (lexical order) MUST be considered for
execution by the WS-HumanTask Processor. The task is set to state Ready
after reassignment. Reassignments and notifications are performed in the
lexical order.
A task MAY have multiple start deadlines and completion
deadlines associated with it. Each such deadline encompasses escalation actions
each of which MAY send notifications to certain people. The corresponding set
of people MAY overlap.
As an example, the figure depicts a task that has been
created at time T1. Its two start deadlines would be missed at time T2 and T3,
respectively. The associated escalations whose conditions evaluate to “true”
are triggered. Both, the escalations Esc-1 to Esc-n as well as escalations
Esc-a to Esc-z can involve an overlapping set of people. The completion
deadline would be missed at time T4.
Syntax:
<htd:deadlines>
<htd:startDeadline name="NCName">*
...
<htd:escalation name="NCName">*
<htd:condition expressionLanguage="anyURI"?>?
boolean-expression
</htd:condition>
<htd:toParts>?
<htd:toPart part="NCName"
expressionLanguage="anyURI"?>+
expression
</htd:toPart>
</htd:toParts>
<!-- notification specified
by reference -->
<htd:localNotification reference="QName">?
<htd:priority expressionLanguage="anyURI"?>?
integer-expression
</htd:priority>
<htd:peopleAssignments>?
<htd:recipients>
...
</htd:recipients>
</htd:peopleAssignments>
</htd:localNotification>
<!-- notification specified
inline -->
<htd:notification name="NCName">?
...
</htd:notification>
<htd:reassignment>?
<htd:potentialOwners>
...
</htd:potentialOwners>
</htd:reassignment>
</htd:escalation>
</htd:startDeadline>
<htd:completionDeadline name="NCName">*
...
</htd:completionDeadline>
</htd:deadlines>
Example:
The following example shows the specification of a start
deadline with escalations. At runtime, the following picture depicts the result
of what is specified in the example:
The human task is created at T1. If it has not been started, i.e., no person is
working on it until T2, then the escalation “reminder” is triggered that
notifies the potential owners of the task that work is waiting for them. In
case the task has high priority then at the same time the regional manager is
informed. If the task amount is greater than or equal 10000 the task is reassigned
to Alan.
In case that task has been started before T2 was reached,
then the start deadline is deactivated, no escalation occurs.
<htd:startDeadline name="sendNotifications">
<htd:documentation xml:lang="en-US">
If not started within 3 days,
- escalation notifications are sent
if the claimed amount is less
than 10000 - to the task's potential
owners to remind them or
their todo - to the regional manager, if
this approval is of high
priority (0,1, or 2) - the task is
reassigned to Alan if the
claimed amount is greater than or equal
10000
</htd:documentation>
<htd:for>P3D</htd:for>
<htd:escalation name="reminder">
<htd:condition>
<![CDATA[
htd:getInput("ClaimApprovalRequest")/amount < 10000
]]>
</htd:condition>
<htd:toParts>
<htd:toPart name="firstname">
htd:getInput("ClaimApprovalRequest","ApproveClaim")/firstname
</htd:toPart>
<htd:toPart name="lastname">
htd:getInput("ClaimApprovalRequest","ApproveClaim")/lastname
</htd:toPart>
</htd:toParts>
<htd:localNotification reference="tns:ClaimApprovalReminder">
<htd:documentation xml:lang="en-US">
Reuse the predefined notification
"ClaimApprovalReminder".
Overwrite the recipients
with the task's potential owners.
</htd:documentation>
<htd:peopleAssignments>
<htd:recipients>
<htd:from>htd:getPotentialOwners("ApproveClaim")</htd:from>
</htd:recipients>
</htd:peopleAssignments>
</htd:localNotification>
</htd:escalation>
<htd:escalation name="highPrio">
<htd:condition>
<![CDATA[
(htd:getInput("ClaimApprovalRequest")/amount < 10000
&&
htd:getInput("ClaimApprovalRequest")/prio <= 2)
]]>
</htd:condition>
<!-- task input implicitly
passed to the notification -->
<htd:notification name="ClaimApprovalOverdue">
<htd:documentation xml:lang="en-US">
An inline defined
notification using the approval data as its
input.
</htd:documentation>
<htd:interface portType="tns:ClaimsHandlingPT"
operation="escalate" />
<htd:peopleAssignments>
<htd:recipients>
<htd:from logicalPeopleGroup="regionalManager">
<htd:argument name="region">
htd:getInput("ClaimApprovalRequest")/region
</htd:argument>
</htd:from>
</htd:recipients>
</htd:peopleAssignments>
<htd:presentationElements>
<htd:name xml:lang="en-US">Claim approval overdue</htd:name>
<htd:name xml:lang="de-DE">
Überfällige
Schadensforderungsgenehmigung
</htd:name>
</htd:presentationElements>
</htd:notification>
</htd:escalation>
<htd:escalation name="highAmountReassign">
<htd:condition>
<![CDATA[
htd:getInput("ClaimApprovalRequest")/amount >= 10000
]]>
</htd:condition>
<htd:reassignment>
<htd:documentation>
Reassign task to Alan if
amount is greater than or equal
10000.
</htd:documentation>
<htd:potentialOwners>
<htd:from>
<htd:literal>
<htt:organizationalEntity>
<htt:user>Alan</htt:user>
</htt:organizationalEntity>
</htd:literal>
</htd:from>
</htd:potentialOwners>
</htd:reassignment>
</htd:escalation>
</htd:startDeadline>
All timeouts and escalations apply to sub tasks also. If
htd:escalation is triggered for a sub task, then any htd:reassignment MUST be
applied only to that.
Human tasks can have a number of different states and
substates. The state diagram for human tasks below shows the different states
and the transitions between them.
Upon creation, a task goes into its initial state Created.
Task creation starts with the initialization of its properties in the following
order:
- Input message
- Priority
- Generic human roles (such as excluded owners, potential owners and
business administrators) are made available in the lexical order of their
definition in the people assignment definition with the constraint that
excluded owners are taken into account when evaluating the potential
owners.
- All other properties are evaluated after these properties in an
implementation dependent order.
Task creation succeeds irrespective of whether the people
assignment returns a set of values or an empty set. People queries that cannot
be executed successfully are treated as if they were returning an empty set.
If potential owners were not assigned automatically during
task creation then they MUST be assigned explicitly using nomination, which is
performed by the task’s business administrator. The result of evaluating
potential owners removes the excluded owners from results. The task remains in
the state Created until it is activated (i.e., an activation timer has
been specified) and has potential owners.
When the task has a single potential owner, it transitions
into the Reserved state, indicating that it is assigned to a single
actual owner. Otherwise (i.e., when it has multiple potential owners or is
assigned to a work queue), it transitions into the Ready state,
indicating that it can be claimed by one of its potential owners. Once a
potential owner claims the task, it transitions into the Reserved state,
making that potential owner the actual owner.
Once work is started on a task that is in state Ready
or Reserved, it goes into the InProgress state, indicating that
it is being worked on – if the transition is from Ready, the user
starting the work becomes its actual owner.
On successful completion of the work, the task transitions
into the Completed final state. On unsuccessful completion of the work
(i.e., with an exception), the task transitions into the Failed final
state.
The lifecycle of sub tasks is the same as that of the main
task.
For human tasks that have subtasks two different cases
exist, with different implications:
- Tasks with subtasks where an actual owner is required
- Tasks with subtasks where no actual owner is required
The first case has the sub-case where a potential owner has
been modeled on the primary task and subtasks have been modeled that are
activated either manually or automatically. Another sub-case of the first case
is the one where no potential owner has been modeled and thus nomination has to
occur. In all cases there is an actual owner eventually and the primary task
goes through the state transitions from Created to Ready to Reserved
to InProgress, etc.
In the second case where no actual owner is desired the
human task (the primary task) directly transitions from state Created to
InProgress. Subtasks are always instantiated automatically.
The current actual owner of a human task can release
a task to again make it available for all potential owners. A task can be
released from active states that have an actual owner (Reserved, InProgress),
transitioning it into the Ready state. Business data associated with the
task (intermediate result data, ad-hoc attachments and comments) is kept.
A task that is currently InProgress can be stopped by
the actual owner, transitioning it into state Reserved. Business data
associated with the task as well as its actual owner is kept.
Task’s potential owners, actual owner or business
administrator can delegate a task to another user, making that user the
actual owner of the task, and also adding her to the list of potential owners
in case she is not, yet. A task can be delegated when it is in an active state
(Ready, Reserved, InProgress), and transitions the task
into the Reserved state. Business data associated with the task is kept.
Similarly, task’s potential owners, actual owner or business
administrator can forward an active task to another person or a set of people,
replacing himself by those people in the list of potential owners. Potential
owners can only forward tasks that are in the Ready state. Forwarding is
possible if the task has a set of individually assigned potential owners, not
if its potential owners are assigned using one or many groups. If the task is
in the Reserved or InProgress state then the task is implicitly
released first, that is, the task is transitioned into the Ready state.
Business data associated with the task is kept. The user performing the forward
is removed from the set of potential owners of the task, and the forwardee is
added to the set of potential owners.
Task state transitions may be caused by the invocation of
API operations (see section 7 “Programming Interfaces”) or by events (see
section 8 “Interoperable Protocol for Advanced Interaction with Human Tasks”).
If a task has sub tasks then some state transitions are
propagated to these sub tasks. Conversely, if a task has a parent task then some
state transitions are propagated to that parent task.
The following table defines how task state transitions MUST
be propagated to sub tasks and to parent tasks.
|
Task Event
|
Effect on Sub Tasks
(downward propagation)
|
Effect on Parent Task
(upward propagation)
|
|
suspend operation invoked
|
suspend (ignored if not applicable, e.g., if the sub task
is already suspended or in a final state) – a suspend event is propagated recursively
if the sub task is not in a final state
|
none
|
|
suspend event received (from a parent task)
|
|
resume operation invoked
|
resume (ignored if not applicable, e.g., if the sub task
is not suspended or in a final state) – a resume event is propagated recursively
if the sub task is not in a final state
|
none
|
|
resume event received (from a parent task)
|
|
complete operation invoked
|
exit (ignored if the sub task is in a final state)
|
completion may be initiated (see section 4.7 “Completion
Behavior”)
|
|
complete event received
|
|
fail operation invoked
|
exit (ignored if the sub task is in a final state)
|
none (if “manual” activation pattern), otherwise fail
|
|
fail event received
|
|
non-recoverable error event received
|
|
exit event received
|
exit (ignored if the sub task is in a final state)
|
none
|
|
skip operation invoked (and the task is “skipable”)
|
skip
|
completion may be initiated (see section 4.7 “Completion
Behavior”)
|
All other task state transitions MUST NOT affect sub tasks
or a parent task.
4.11 History of a Human Task
Task
lifecycle state changes and data changes are maintained as a history of task
events. Task events contain the following data:
Task
Event
- event id
- event time
- task id
- user (principal) that caused the state change
- event type (e.g. claim task).
- event data (e.g. data used in setOutput) and fault name
(event was setFault)
- startOwner - the actual owner before the event.
- endOwner - the actual owner after the event.
- task status at the end of the event
For example,
if the User1 delegated a task to User2, then the user and startOwner would be
User1, endOwner would be User2. The event data would be the
<htt:organizationalEntity/> element used in the WSHT delegate operation.
The system
generated attribute 'event id' MUST be unique on a per task basis.
4.11.1 Task Event
Types and Data
Some task
events (e.g. setOutput) may have data associated with event and others may not
(e.g. claim). The following table lists the event types and the data.
|
Actions/Operations
resulting in task events
|
|
Event Type
|
Owner Change
|
State Change
|
Data Value
|
|
created
|
maybe
|
yes
|
|
|
claim
|
yes
|
yes
|
|
|
Start
|
maybe
|
yes
|
|
|
stop
|
|
yes
|
|
|
release
|
yes
|
yes
|
|
|
suspend
|
|
yes
|
|
|
suspendUntil
|
|
yes
|
<htt:pointOfTime>2020-12-12T12:12:12Z </htt:pointOfTime>
or
<htt:timePeriod>PT1H</htt:timePeriod> |
|
resume
|
|
yes
|
|
|
complete
|
|
yes
|
<htt:taskData> <ns:someData xmlns:ns="urn:foo"/> </htt:taskData> |
|
remove
|
|
|
|
|
fail
|
|
yes
|
<htt:fail> <htt:identifier>urn:b4p:1</htt:identifier> <htt:faultName>fault1</htt:faultName> <htt:faultData> <someFaultData xmlns="urn:foo"/> </htt:faultData> </htt:fail> |
|
setPriority
|
|
|
<htt:priority>500000</htt:priority> |
|
addAttachment
|
|
|
<htt:addAttachment> <htt:identifier>urn:b4p:1</htt:identifier> <htt:name>myAttachment</htt:name> <htt:accessType>MIME</htt:accessType> <htt:contentType>text/plain</htt:contentType> <htt:attachment/> </htt:addAttachment> |
|
deleteAttachment
|
|
|
<htt:identifier> urn:b4p:1</htt:identifier> |
|
addComment
|
|
|
<htt:text>text for comment</htt:text> |
|
updateComment
|
|
|
<htt:text>new text for comment</htt:text> |
|
deleteComment
|
|
|
<htt:text>deleted comment text</htt:text> |
|
skip
|
|
yes
|
|
|
forward
|
maybe
|
maybe
|
<htt:organizationalEntity> <htt:user>user5</htt:user> <htt:user>user6</htt:user> </htt:organizationalEntity> |
|
delegate
|
yes
|
maybe
|
<htt:organizationalEntity> <htt:user>user5</htt:user> </htt:organizationalEntity> |
|
setOutput
|
|
|
<htt:setOutput> <htt:identifier>urn:b4p:1</htt:identifier> <htt:part>outputPart1</htt:part> <htt:taskData> <ns:someData xmlns:ns="urn:foo" /> </htt:taskData> </htt:setOutput> |
|
deleteOutput
|
|
|
|
|
setFault
|
|
|
<htt:setFault> <htt:identifier>urn:b4p:1</htt:identifier> <htt:faultName>fault1</htt:faultName> <htt:faultData><someFault xmlns="urn:fault"/></htt:faultData> </htt:setFault> |
|
deleteFault
|
|
|
|
|
activate
|
maybe
|
yes
|
|
|
nominate
|
maybe
|
maybe
|
<htt:organizationalEntity> <htt:user>user1</htt:user> <htt:user>user2</htt:user> </htt:organizationalEntity> |
|
setGenericHumanRole
|
|
|
<htt:setGenericHumanRole> <htt:identifier>urn:b4p:1</htt:identifier> <htt:genericHumanRole>businessAdministrators</htt:genericHumanRole> <htt:organizationalEntity> <htt:user>user7</htt:user> <htt:user>user8</htt:user> </htt:organizationalEntity> </htt:setGenericHumanRole> |
|
expire
|
|
yes
|
|
|
escalated
|
|
|
|
|
cancel
|
|
|
|
4.11.2 Retrieving the History
There is a
getTaskHistory operation that allows a client to query the system and retrieve
a list of task events that represent the history of the task. This operation
can:
- Return a list of task events with optional data
- Return a list of task events without optional event data
- Return a subset of the events based on a range (for
paging)
- Return a filtered list of events.
The option
to whether or not to include event data is useful since in some cases the event
data content (e.g. setOutput) may be large. In a typical case, an API client
should be able to query the system to get a "light weight" response
of events (e.g. with out event data) and then when necessary, make an
additional API call to get a specific event details with data. The latter can
be accomplished by specifying the event id when invoking the getTaskHistory
operation.
The XML
Schema definition of the filter is the following:
<xsd:complexType name="tTaskHistoryFilter">
<xsd:choice>
<xsd:element name="eventId"
type="xsd:integer" />
<!-- Filter to
allow narrow down query by status, principal,
event Type. -->
<xsd:sequence>
<xsd:element name="status"
type="tStatus" minOccurs="0"
maxOccurs="unbounded" />
<xsd:element name="eventType"
type="tTaskEventType" minOccurs="0"
maxOccurs="unbounded"
/>
<xsd:element name="principal"
type="xsd:string" minOccurs="0" />
<xsd:element name="afterEventTime"
type="xsd:dateTime"
minOccurs="0" />
<xsd:element name="beforeEventTime"
type="xsd:dateTime"
minOccurs="0" />
</xsd:sequence>
</xsd:choice>
</xsd:complexType>
<xsd:simpleType name="tTaskEventType">
<xsd:restriction base="xsd:string">
<xsd:enumeration value="create"
/>
<xsd:enumeration value="claim"
/>
<xsd:enumeration value="start"
/>
<xsd:enumeration value="stop"
/>
<xsd:enumeration value="release"
/>
<xsd:enumeration value="suspend"
/>
<xsd:enumeration value="suspendUntil"
/>
<xsd:enumeration value="resume"
/>
<xsd:enumeration value="complete"
/>
<xsd:enumeration value="remove"
/>
<xsd:enumeration value="fail"
/>
<xsd:enumeration value="setPriority"
/>
<xsd:enumeration value="addAttachment"
/>
<xsd:enumeration value="deleteAttachment"
/>
<xsd:enumeration value="addComment"
/>
<xsd:enumeration value="updateComment"
/>
<xsd:enumeration value="deleteComment"
/>
<xsd:enumeration value="skip"
/>
<xsd:enumeration value="forward"
/>
<xsd:enumeration value="delegate"
/>
<xsd:enumeration value="setOutput"
/>
<xsd:enumeration value="deleteOutput"
/>
<xsd:enumeration value="setFault"
/>
<xsd:enumeration value="deleteFault"
/>
<xsd:enumeration value="activate"
/>
<xsd:enumeration value="nominate"
/>
<xsd:enumeration value="setGenericHumanRole"
/>
<xsd:enumeration value="expire"
/>
<xsd:enumeration value="escalated"
/>
</xsd:restriction>
</xsd:simpleType>
The XML
Schema definition of events returned for the history is the following:
<xsd:element
name="taskEvent">
<xsd:complexType>
<xsd:annotation>
<xsd:documentation>
A detailed event that represents a change in the task's state.
</xsd:documentation>
</xsd:annotation>
<xsd:sequence>
<!-- event id
- unique per task -->
<xsd:element name="id"
type="xsd:integer" />
<!-- event
date time -->
<xsd:element name="eventTime"
type="xsd:dateTime" />
<!-- task ID -->
<xsd:element name="identifier"
type="xsd:anyURI" />
<xsd:element name="principal"
type="xsd:string" minOccurs="0"
nillable="true" />
<!-- Event
type. Note - using a restricted type limits
extensibility to add custom event types. -->
<xsd:element name="eventType"
type="tTaskEventType" />
<!-- actual
owner of the task before the event -->
<xsd:element name="startOwner"
type="xsd:string" minOccurs="0"
nillable="true" />
<!-- actual
owner of the task after the event -->
<xsd:element name="endOwner"
type="xsd:string" minOccurs="0"
nillable="true" />
<!-- WSHT task
status -->
<xsd:element name="status"
type="tStatus" />
<!-- boolean to
indicate this event has optional data -->
<xsd:element name="hasData"
type="xsd:boolean" minOccurs="0" />
<xsd:element name="eventData"
type="xsd:anyType" minOccurs="0"
nillable="true" />
<xsd:element name="faultName"
type="xsd:string" minOccurs="0"
nillable="true" />
<!--
extensibility -->
<xsd:any namespace="##other"
processContents="lax" minOccurs="0"
maxOccurs="unbounded" />
</xsd:sequence>
</xsd:complexType>
</xsd:element>
The <leanTask>
element is used to specify human tasks. This section introduces the syntax for
the element, and individual properties are explained in subsequent sections.
The element <leanTask> derives from the type htd:tTask, with the
following augmentations:
<htd:leanTask>
<htd:interface>….</htd:interface>
<htd:messageSchema>...</htd:messageSchema>
... All elements from htd:task except
<interface> and <composition> ...
<htd:composition>….</htd:composition>
</htd:leanTask>
The following attributes and elements are defined for lean
tasks and are different from the definition of htd:task:
- interface
– Lean tasks are created through the CreateLeanTask operation (section
7.3.4), and their input message is derived from the messageSchema
element. Therefore, an interface element might contradict that
information, and to prevent that, interface is banned.
- messageSchema
– Identifies the schema of the inputMessage and outputMessage for the lean
task, and if the renderings element is not defined, the WS-HumanTask
Processor can use this to generate a rendering or pass this data directly
to a WS-HumanTask Client such that the rendering is generated from the
messageSchema.
- composition
– Lean tasks cannot have explicitly declared subtasks as defined for
composite tasks (section 4.6), consequently, this element is banned.
This element references the schema of the data that is used
for both the input and output messages of the lean task.
<messageSchema>
<messageField name="xsd:NCName" type="xsd:QName">*
<messageDisplay xml:lang="xsd:language"?>+
Language specific display
</messageDisplay>
<messageChoice
namevalue="xsd:NCNameanySimpleType">*
<messageDisplay
xml:lang="xsd:language"?>+
Language specific display
</messageDisplay>
</messageChoice>
</messageField>
</messageSchema>
The <messageSchema>
element specifies the data that a Lean Task accepts. As it is currently
defined, a WS-HumanTask Processor could render the following form elements in a
way that only requires vendor-specific knowledge between the WS-HumanTask
Processor and the WS-HumanTask Client and no vender-specific knowledge between
the WS-HumanTask Processor and the WS-HumanTask Parent:
—
String
—
Integer
—
Float
—
Date Time
—
Bool
—
Enumeration (Choice)
Each of these is accomplished by using an instance of a <messageField>.
For string, integer, float, datetime, and boolean fields, this is accomplished
by using the type attribute of the <messageField>. The supported set of values are:
xsd:string, xsd:integer, xsd:float, xsd:datetime, and xsd:boolean, all
respectively matching the list above. If a simple rendering language like HTML
were used, this could be accomplished by using a textbox control that simply
had special rules about the format of its input.
The enumeration field uses a combination of one <messageField>
element and possibly many child <messageChoice> elements. Each child <messageChoice>
represents one possible option that could be selected from the enumeration. If
a simple rendering language like HTML were used, this could be shown using
radio buttons, a dropdown list, or a listbox that only supports single
selection.
For all <messageField> and <messageChoice> elements, it is possible to
specify a per-lanugage <messageDisplay>
element. It uses xml:lang,
a standard XML attribute, to define the language of the enclosed information.
This attribute uses tags according to RFC 1766 (see [RFC1766]). There could be
zero or more <messageDisplay>
elements. A <messageField>
or <messageChoice>
MUST NOT specify multiple <messageDisplay> elements having the same value for the
attribute xml:lang.
The combination of <messageSchema> and <possibleOutcomes> can be used to
generate a form of sufficient functionality for many simple tasks, precluding
the need for a renderings element.
Example:
<messageSchema>
<messageField
name="amount"
type="xsd:float">
<messageDisplay xml:lang="en-us">Amount</messageDisplay>
<messageDisplay xml:lang="fr-fr”>Quantité</messageDisplay>
</messageField>
<messageField name="currencyUnit"
type="xsd:string">
<messageDisplay xml:lang="en-us">Currency<messageDisplay>
<messageDisplay xml:lang="fr-fr">Devise</messageDisplay>
<messageChoice namevalue="USD">
<messageDisplay xml:lang="en-us">US Dollars</messageDisplay>
<messageDisplay xml:lang="fr-fr">US Dollars</messageDisplay>
</messageChoice>
<messageChoice namevalue="EURO">
<messageDisplay xml:lang="en-us">Euro Dollars</messageDisplay>
<messageDisplay xml:lang="fr-fr">Euros</messageDisplay>
</messageChoice>
</messageField>
</messageSchema>
The following XML could be used for a simple ‘ToDoTask’:
<htd:task
name="ToDoTask">
<htd:messageSchema
/>
<htd:possibleOutcomes>
<htd:possibleOutcome
name="Completed"
/>
... language specific translations ...
</htd:possibleOutcomes>
<htd:delegation
potentialDelegates="anybody"
/>
<htd:presentationElements>
<htd:name>ToDo
Task</htd:name>
... language specific translations ...
<htd:subject>Please
complete the described work</htd:subject>
... language specific translations ...
<htd:description
contentType="mimeTypeString"
/>
... language specific translations ...
</htd:presentationElements>
</htd:task>
Notifications are used to notify a person or a group of
people of a noteworthy business event, such as that a particular order has been
approved, or a particular product is about to be shipped. They are also used in
escalation actions to notify a user that a task is overdue or a task has not
been started yet. The person or people to whom the notification will be
assigned to could be provided, for example, as result of a people query to
organizational model.
Notifications are simple human interactions that do not
block the progress of the caller, that is, the caller does not wait for the
notification to be completed. Moreover, the caller cannot influence the
execution of notifications, e.g. notifications are not terminated if the caller
terminates. The caller, i.e. an application, a business process or an
escalation action, initiates a notification passing the required notification
data. The notification appears on the task list of all notification recipients.
After a notification recipient removes it, the notification disappears from the
recipient’s task list.
A notification MAY have multiple recipients and optionally
one or many business administrators. The generic human roles task initiator,
task stakeholders, potential owners, actual owner and excluded owners play no
role.
Presentation elements and task rendering, as described in
sections 4.3 and 4.4 respectively, are used for notifications also. In most
cases the subject line and description are sufficient information for the
recipients, especially if the notifications are received in an e-mail client or
mobile device. But in some cases the notifications can be received in a
proprietary client so the notification can support a proprietary rendering
format to enable this to be utilized to the full, such as for rendering data
associated with the caller invoking the notification. For example, the
description could include a link to the process audit trail or a button to
navigate to business transactions involved in the underlying process.
Notifications do not have ad-hoc attachments, comments or
deadlines.
Definition of notifications
<htd:notification name="NCName">
<htd:interface portType="QName"
operation="NCName"/>
<htd:priority expressionLanguage="anyURI"?>?
integer-expression
</htd:priority>
<htd:peopleAssignments>
<htd:recipients>
...
</htd:recipients>
<htd:businessAdministrators>?
...
</htd:businessAdministrators>
</htd:peopleAssignments>
<htd:presentationElements>
...
</htd:presentationElements>
<htd:renderings>?
...
</htd:renderings>
</htd:notification>
The following attributes and elements are defined for
notifications:
·
name: This
attribute is used to specify the name of the notification. The name combined
with the target namespace MUST uniquely identify a notification in the
notification definition. The attribute is mandatory. It is not used for
notification rendering.
·
interface: This
element is used to specify the operation used to invoke the notification. The
operation is specified using WSDL, that is a WSDL port type and WSDL operation
are defined. The element and its portType
and operation attributes are
mandatory. In the operation
attribute, a WS-HumanTask Definition MUST reference a one-way WSDL operation.
·
priority: This
element is used to specify the priority of the notification. It is an optional
element which value is an integer expression. If present then the WS-HumanTask
Definition MUST specify a value between 0 and 10, where 0 is the highest priority
and 10 is the lowest. If not present, the priority of the notification is
considered as 5. The result of the expression evaluation is of type htt:tPriority. The expressionLanguage attribute specifies
the language used in the expression. The attribute is optional. If not
specified, the default language as inherited from the closest enclosing element
that specifies the attribute is used.
·
peopleAssignments:
This element is used to specify people assigned to the notification. The
element is mandatory. A WS-HumanTask Definition MUST include a people
assignment for recipients and MAY include a people assignment for business
administrators.
·
presentationElements:
The element is used to specify different information used to display the
notification, such as name, subject and description, in a task list. The
element is mandatory. See section 4.3 for more information on presentation
elements.
·
rendering: The
element is used to specify rendering method. It is optional. If not present,
notification rendering is implementation dependent. See section 4.4 for more information on rendering.
Same as human tasks, notifications are in pseudo-state Inactive
before they are activated. Once they are activated they move to the Ready
state. This state is observable, that is, when querying for notifications then
all notifications in state Ready are returned. When a notification is
removed then it moves into the final pseudo-state Removed.
A number of applications are involved in the life cycle of a
task. These comprise:
·
The task list client, i.e. a client capable of displaying
information about the task under consideration
·
The requesting application, i.e. any partner that has initiated
the task
·
The supporting application, i.e. an application launched by the
task list client to support processing of the task.
The task infrastructure provides access to a given task. It
is important to understand that what is meant by task list client is the
software that presents a UI to one authenticated user, irrespective of whether
this UI is rendered by software running on server hardware (such as in a
portals environment) or client software (such as a client program running on a
users workstation or PC).
A given task exposes a set of operations to this end. A
WS-HumanTask Processor MUST provide the operations listed below and an
application (such as a task list client) can use these operations to manipulate
the task. All operations MUST be executed in a synchronous fashion and MUST
return a fault if certain preconditions do not hold. For operations that are
not expected to return a response they MAY return a void message. The above
applies to notifications also.
An operation takes a well-defined set of parameters as its
input. Passing an illegal parameter or an illegal number of parameters MUST
result in the hta:illegalArgumentFault
being returned. Invoking an operation that is not allowed in the current state
of the task MUST result in an hta:illegalStateFault.
By default, the identity of the person on behalf of which
the operation is invoked is passed to the task. When the person is not
authorized to perform the operation the hta:illegalAccessFault
and hta:recipientNotAllowed MUST
be returned in the case of tasks and notifications respectively.
Invoking an operation that does not apply to the task type
(e.g., invoking claim on a notification) MUST result in an hta:illegalOperationFault.
The language of the person on behalf of which the operation
is invoked is assumed to be available to operations requiring that information,
e.g., when accessing presentation elements.
For an overview of which operations are allowed in what
state, refer to section 4.10 “Human Task Behavior and State Transitions”. For a
formal definition of the allowed operations, see Appendix D “WS-HumanTask Client API Port Type".
For information which generic human roles are authorized to
perform which operations, refer to section 7.1.4 “Operation Authorizations”.
This specification does not stipulate the authentication,
language passing, addressing, and binding scheme employed when calling an
operation. This can be achieved using different mechanisms (e.g. WS-Security,
WS-Addressing).
Operations are executed by end users, i.e. actual or
potential owners. The identity of the user is implicitly passed when invoking
any of the operations listed in the table below.
If the task is in a predefined state listed as valid
pre-state before the operation is invoked then, upon successful completion, the
task MUST be in the post state defined for the operation. If the task is in a
predefined state that is not listed as valid pre-state before the operation is
invoked then the operation MUST be rejected and MUST NOT cause a task state
transition.
All of the operations below apply to tasks and sub tasks
only unless specifically noted below.
The column “Supports Batch Processing” below
indicates if an operation can be used to process multiple human tasks at the
same time. One or more operations on individual tasks may fail without causing
the overall batch operation to fail.
|
Operation Name
|
Description
|
Parameters
|
Supports Batch Processing
|
Pre-State
|
Post-State
|
|
claim
|
Claim responsibility for a task, i.e. set the
task to status Reserved
|
In
·
task identifier
Out
·
void
|
Yes
|
Ready
|
Reserved
|
|
start
|
Start the execution of the task, i.e. set the
task to status InProgress.
|
In
Out
|
Yes
|
Ready
Reserved
|
InProgress
|
|
stop
|
Cancel/stop the processing of the task. The task
returns to the Reserved state.
|
In
Out
|
Yes
|
InProgress
|
Reserved
|
|
release
|
Release the task, i.e. set the task back to
status Ready.
|
In
Out
|
Yes
|
InProgress
Reserved
|
Ready
|
|
suspend
|
Suspend the task.
|
In
Out
|
Yes
|
Ready
Reserved
InProgress
|
Suspended/Ready (from Ready)
Suspended/Reserved (from Reserved)
Suspended/InProgress (from InProgress)
|
|
suspendUntil
|
Suspend the task for a given period of time or
until a fixed point in time. The WS-HumanTask Client MUST specify either a
period of time or a fixed point in time.
|
In
task identifiertime period point of time
Out
|
Yes
|
Ready
Reserved
InProgress
|
Suspended/Ready (from Ready)
Suspended/Reserved (from Reserved)
Suspended/InProgress (from InProgress)
|
|
resume
|
Resume a suspended task.
|
In
Out
|
Yes
|
Suspended/Ready
Suspended/Reserved
Suspended/InProgress
|
Ready (from Suspended/Ready)
Reserved (from Suspended/Reserved)
InProgress (from Suspended/InProgress)
|
|
complete
|
Execution of the task finished successfully. If
no output data is set the operation MUST return hta:illegalArgumentFault.
|
In
task identifieroutput data of task
Out
|
Yes
|
InProgress
|
Completed
|
|
remove
|
Applies to notifications only.
Used by notification recipients to remove the
notification permanently from their task list client. It will not be returned
on any subsequent retrieval operation invoked by the same user.
|
In
Out
|
Yes
|
Ready (Notification state)
|
Removed (Notification state)
|
|
fail
|
Execution of the task fails and a fault is
returned.
The fault hta:illegalOperationFault
MUST be returned if the task interface defines no faults.
If fault name or fault data is not set the
operation MUST return hta:illegalArgumentFault.
|
In
task identifierfault – contains the fault name and fault
data
Out
|
Yes
|
InProgress
|
Failed
|
|
setPriority
|
Change the priority of the task. The WS-HumanTask
Client MUST specify the integer value of the new priority.
|
In
task identifierpriority (htt:tPriority)
Out
|
Yes
|
(any state)
|
(no state transition)
|
|
addAttachment
|
Add attachment to a task. Returns an identifier for the
attachment.
|
In
- task identifier
- attachment name
- access type
- content type
- attachment
Out
|
No
|
(any state)
|
(no state transition)
|
|
addCommentgetAttachmentInfos
|
Get attachment information for all attachments associated
with the task. Add a comment to a task. Returns an identifier
that can be used to later update or delete the comment.
|
In
- task identifier
- plain text
Out
list of attachment data (list of htt:attachmentInfo)
comment identifier
|
No
|
(any state)
|
(no state transition)
|
|
claimgetAttachment
|
GetClaim responsibility
for a task, i.e. set the task attachment with the
given identifier.to status Reserved
|
In
·
task identifier
Out
·
htt:attachmentvoid
|
NoYes
|
(any state)Ready
|
(no state transition)Reserved
|
|
complete
|
Execution of the task finished successfully. The
fault hta:illegalStateFault
MUST be returned if the task interface defines non-empty task output but no
output data is provided as the input parameter and the task output data has
not been set previously, e.g. using operation setOutput.
|
In
- task identifier
- output data of task (optional)
Out
|
Yes
|
InProgress
|
Completed
|
|
delegate
|
Assign the task to one user and set the task to
state Reserved. If the recipient was not a potential owner then this
person MUST be added to the set of potential owners.
For details on delegating human tasks refer to
section 4.10.3.
|
In
- task identifier
- organizational entity (htt:tOrganizationalEntity)
Out
|
Yes
|
Ready
Reserved
InProgress
|
Reserved
|
|
deleteAttachment
|
Delete the attachment with the specified identifier from
the task.
Attachments provided by the enclosing context MUST NOT be
affected by this operation.
|
In
- task identifier
- attachment identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
deleteCommentaddComment
|
Add a comment to a task. Returns an identifier
that can be used to later update or delete the comment.Deletes
the identified comment.
|
In
- task identifier
plain text
Out
Out
|
No
|
(any state)
|
(no state transition)
|
|
deleteFaultupdateComment
|
UpdatesDeletes
the identified comment withfault
name and fault data of the supplied new text.task.
|
In
- task identifier
comment identifierplain text
Out
|
No
|
(any state)InProgress
|
(no state transition)
|
|
deleteOutputdeleteComment
|
Deletes the identified comment.output
data of the task.
|
In
- task identifier
comment identifier
Out
|
No
|
(any state)InProgress
|
(no state transition)
|
|
getComments
|
Get all comments of a task
|
In
Out
list of comments (list of htt:comment)
|
No
|
(any state)
|
(no state transition)
|
|
failskip
|
SkipExecution of
the task. fails and a fault is
returned.
If the task is not skipable then the The
fault hta:illegalOperationFault
MUST be returned if the task interface defines no faults.
The fault hta:illegalStateFault
MUST be returned if the task interface defines at least one faults but either
fault name or fault data is not provided and it has not been set previously,
e.g. using operation setFault.
|
In
- task identifier
- fault (optional) – contains the fault name
and fault data
Out
|
Yes
|
Created
Ready
Reserved
InProgress
|
ObsoleteFailed
|
|
forward
|
Forward the task to another organization entity. The
WS-HumanTask Client MUST specify the receiving organizational entity.
Potential owners MAY forward a task while the task is in
the Ready state.
For details on forwarding human tasks refer to section 4.10.3 .
|
In
- task identifier
- organizational entity (htt:tOrganizationalEntity)
Out
|
Yes
|
Ready
Reserved
InProgress
|
Ready
|
|
getAttachmentdelegate
|
Assign the task to one user and set the task to
state Reserved. If the recipient was not a potential owner then this
person MUST be added to the set of potential owners.
For details on delegating human tasks refer to
section 4.10.3.Get
the task attachment with the given identifier.
|
In
- task identifier
organizational entity (htt:tOrganizationalEntity)
Out
voidattachment
identifier
Out
|
YesNo
|
Ready
Reserved
InProgress(any state)
|
Reserved(no state transition)
|
|
getAttachmentInfos
|
Get attachment information for all attachments
associated with the task.
|
In
Out
- list of attachment data (list of htt:attachmentInfo)
|
No
|
(any state)
|
(no state transition)
|
|
getComments
|
Get all comments of a task
|
In
Out
- list of comments (list of htt:comment)
|
No
|
(any state)
|
(no state transition)
|
|
getFault
|
Get the fault data of the task.
|
In
Out
- fault – contains the fault name and fault
data
|
No
|
(any state)
|
(no state transition)
|
|
getInput
|
Get the data for the part of the task's input
message.
|
In
- task identifier
- part name (optional for single part
messages)
Out
|
No
|
(any state)
|
(no state transition)
|
|
getOutcome
|
Get the outcome of the task
|
In
Out
|
No
|
(any state)
|
(no state transition)
|
|
getOutput
|
Get the data for the part of the task's output
message.
|
In
- task identifier
- part name (optional for single part
messages)
Out
|
No
|
(any state)
|
(no state transition)
|
|
getParentTask
|
Returns the superior
composite task of a sub task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
getParentTaskIdentifier
|
Returns the task
identifier of the superior composite task of a sub task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
getRendering
|
Applies to both tasks and notifications.
Returns the rendering specified by the type parameter.
|
In
- task identifier
- rendering type
Out
|
No
|
(any state)
|
(no state transition)
|
|
getRenderingTypes
|
Applies to both tasks and notifications.
Returns the rendering types available for the task or
notification.
|
In
Out
|
No
|
(any state)
|
(no state transition)
|
|
getSubtaskIdentifiersgetTaskDetails
|
Applies to both tasks and notifications.
Returns a
data objectthe identifiers of type htt:tTaskDetails all already created sub tasks of a task
|
In
·
task identifier
Out
- list
of task
(htt:tTaskDetails)identifiers
|
No
|
(any state)
|
(no state transition)
|
|
getSubtasks
|
Returns all sub tasks
of a task (created instances + not yet created sub task definitions)
|
In
·
task identifier
Out
- list of tasks
(list of htt:tTask)
|
No
|
(any state)
|
(no state transition)
|
|
getTaskDescription
|
Applies to both tasks and notifications. Returns the
presentation description in the specified mime type.
|
In
- task identifier
- content type – optional, default is text/plain
Out
|
No
|
(any state)
|
(no state transition)
|
|
getTaskDetailsgetTaskOperations
|
Applies to both tasks. and
notifications.
Returns lista data object
of operations that are available to the authorized
user given the user's role and the state of the task.type
htt:tTaskDetails
|
In
Out
List of available operation.task
(htt:tTaskDetails)
|
No
|
(any state)
|
(no state transition)
|
|
setOutput
|
Set the data for the part of the task's output
message.
|
In
task identifierpart name (optional for single part messages
)output data of task
Out
|
No
|
InProgress
|
(no state transition)
|
|
deleteOutput
|
Deletes the output data of the task.
|
In
Out
|
No
|
InProgress
|
(no state transition)
|
|
setFault
|
Set the fault data of the task.
The fault hta:illegalOperationFault
MUST be returned if the task interface defines no faults.
|
In
task identifierfault – contains the fault name and fault
data
Out
|
No
|
InProgress
|
(no state transition)
|
|
deleteFault
|
Deletes the fault name and fault data of the
task.
|
In
Out
|
No
|
InProgress
|
(no state transition)
|
|
getInput
|
Get the data for the part of the task's input
message.
|
In
task identifierpart name (optional for single part
messages)
Out
|
No
|
(any state)
|
(no state transition)
|
|
getOutput
|
Get the data for the part of the task's output
message.
|
In
task identifierpart name (optional for single part
messages)
Out
|
No
|
(any state)
|
(no state transition)
|
|
getFault
|
Get the fault data of the task.
|
In
Out
fault – contains the fault name and fault
data
|
No
|
(any state)
|
(no state transition)
|
|
getOutcome
|
Get the outcome of the task
|
In
Out
|
No
|
(any state)
|
(no state transition)
|
|
getTaskHistory
|
Get a list of events representing the history of the task.
Filter allows narrowing the results by status,
principal, event Type.
startIndex and maxTasks are integers that
allow paging of the results.
includeData is a Boolean. Data is included with
the returned events only if this is true.
|
In
- task identifier
- filter (htt:tTaskHistoryFilter)
- startIndex
- maxTasks
- includeData
Out
|
No
|
(any state)
|
(no state transition)
|
|
getTaskInstanceData
|
Get any or all details of a task,
except the contents of the attachments. This duplicates functionality
provided by the get() operations above, but provides all the data in a single
round trip.
Properties is an optional space separated list of properties of the
task that should be provided. Properties are named by the local part of the
QName of the element returned for task details.
If it is not specified, then all
properties are returned.
If it is specified, then only
the properties specified are returned. In the case that multiple elements
have the same local part (which can happen for extensions from two different
namespaces) then all of the matching properties are returned.
Some properties of a task may
have multiple values (i.e., taskDescription, input and ouput). When such a
property is requested, all valid values for the property are returned. There
is an exception for the “renderings” property, which is controlled by the
“renderingPreferences” parameter..
renderingPreference is an optional list of
rendering types, in order of preference. If properties is not specified or
includes "renderings", then
If renderingPreferences is not specified, the result
includes all renderings.
If it is specified, then the task's rendering whose type
is earliest in the provided list of rendering types is returned.
|
In
·
properties
Out
- task (htt:tTaskInstanceData)
|
No
|
(any state)
|
(no state transition)
|
|
getTaskOperationsgetSubtasks
|
Returns all sub tasks
of a task (created instances + not yet created sub task definitions)Applies
to tasks. Returns list of operations that are available to
the authorized user given the user's role and the state of the task.
|
In
Out
listList
of tasks (list of
htt:tTask)available
operation.
|
No
|
(any state)
|
(no state transition)
|
|
getSubtaskIdentifiers
|
Returns the
identifiers of all already created sub tasks of a task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
hasSubtasks
|
Returns true if a task has at
least one (already created or not yet created, but specified) sub task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
getParentTask
|
Returns the superior
composite task of a sub task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
getParentTaskIdentifier
|
Returns the task
identifier of the superior composite task of a sub task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
isSubtask
|
Returns true if a
task is a sub task of a superior composite task
|
In
·
task identifier
Out
|
No
|
(any state)
|
(no state transition)
|
|
instantiateSubTask
|
Creates an instantiateable
subtask for the task from the definition of the task.
The fault
hta:illegalArgumentFault MUST be returned if the task does not have an
instantiateable subtask of the given name.
Returns the identifier for the
created subtask.
|
In
·
task identifier
·
subtask name
Out
|
No
|
Reserved
In Progress
|
(no state transition)
|
|
setTaskStartDeadlineExpressionisSubtask
|
SetsReturns
true if a deadline expression for the named start deadlinetask
is a sub task of thea
superior composite task
|
In
·
task identifier
deadline
namedeadline
expression
Out
|
YesNo
|
Created
Ready
Reserved
In Progress(any state)
|
(no state transition)
|
|
release
|
Release the task, i.e. set the task back to
status Ready.
|
In
Out
|
Yes
|
InProgress
Reserved
|
Ready
|
|
setTaskStartDurationExpressionremove
|
Sets a duration
expression for the named start deadline of the taskApplies
to notifications only.
Used by notification recipients to remove the
notification permanently from their task list client. It will not be returned
on any subsequent retrieval operation invoked by the same user.
|
In
deadline
nameduration
expression
Out
|
Yes
|
Created
Ready
Reserved
In Progress (Notification state)
|
(noRemoved (Notification
state transition)
|
|
resume
|
Resume a suspended task.
|
In
Out
|
Yes
|
Suspended/Ready
Suspended/Reserved
Suspended/InProgress
|
Ready (from Suspended/Ready)
Reserved (from Suspended/Reserved)
InProgress (from Suspended/InProgress)
|
|
setFault
|
Set the fault data of the task.
The fault hta:illegalOperationFault
MUST be returned if the task interface defines no faults.
|
In
- task identifier
- fault – contains the fault name and fault
data
Out
|
No
|
InProgress
|
(no state transition)
|
|
setOutput
|
Set the data for the part of the task's output
message.
|
In
- task identifier
- part name (optional for single part messages
)
- output data of task
Out
|
No
|
InProgress
|
(no state transition)
|
|
setPriority
|
Change the priority of the task. The WS-HumanTask
Client MUST specify the integer value of the new priority.
|
In
- task identifier
- priority (htt:tPriority)
Out
|
Yes
|
(any state)
|
(no state transition)
|
|
setTaskCompletionDeadlineExpression
|
Sets a deadline expression for
the named completion deadline of the task
|
In
- task identifier
- deadline name
- deadline
expression
Out
void
|
Yes
|
Created
Ready
Reserved
In Progress
|
(no state transition)
|
|
setTaskCompletionDurationExpression
|
Sets a duration expression for
the named completion deadline of the task
|
In
- task identifier
- deadline name
- duration
expression
Out
void
|
Yes
|
Created
Ready
Reserved
In Progress
|
(no state transition)
|
|
setTaskStartDeadlineExpression
|
Sets a deadline
expression for the named start deadline of the task
|
In
- task
identifier
- deadline
name
- deadline
expression
Out
|
Yes
|
Created
Ready
Reserved
In Progress
|
(no state transition)
|
|
setTaskStartDurationExpression
|
Sets a duration
expression for the named start deadline of the task
|
In
- task
identifier
- deadline
name
- duration
expression
Out
void
|
Yes
|
Created
Ready
Reserved
In Progress
|
(no state transition)
|
|
skip
|
Skip the task.
If the task is not skipable then the fault hta:illegalOperationFault
MUST be returned.
|
In
Out
|
Yes
|
Created
Ready
Reserved
InProgress
|
Obsolete
|
|
start
|
Start the execution of the task, i.e. set the
task to status InProgress.
|
In
Out
|
Yes
|
Ready
Reserved
|
InProgress
|
|
stop
|
Cancel/stop the processing of the task. The task
returns to the Reserved state.
|
In
Out
|
Yes
|
InProgress
|
Reserved
|
|
suspend
|
Suspend the task.
|
In
Out
|
Yes
|
Ready
Reserved
InProgress
|
Suspended/Ready (from Ready)
Suspended/Reserved (from Reserved)
Suspended/InProgress (from InProgress)
|
|
suspendUntil
|
Suspend the task for a given period of time or
until a fixed point in time. The WS-HumanTask Client MUST specify either a
period of time or a fixed point in time.
|
In
- task identifier
- time period
- point of time
Out
|
Yes
|
Ready
Reserved
InProgress
|
Suspended/Ready (from Ready)
Suspended/Reserved (from Reserved)
Suspended/InProgress (from InProgress)
|
|
updateComment
|
Updates the identified comment with the supplied
new text.
|
In
- task identifier
- comment identifier
- plain text
Out
|
No
|
(any state)
|
(no state transition)
|
Simple query operations allow retrieving task data. These
operations MUST be supported by a WS-HumanTask Processor. The identity of the
user is implicitly passed when invoking any of the following operations.
The following operations will return both matching tasks and
sub tasks.
|
Operation Name
|
Description
|
Parameters
|
Authorization
|
|
getMyTaskAbstracts
|
Retrieve the task abstracts. This operation is used to
obtain the data required to display a task list.
If no task type has been
specified then the default value “ALL” MUST be used.
If no generic human role has been specified then the
default value “actualOwner” MUST be used.
If no work queue has been specified then only personal
tasks MUST be returned. If the work queue is specified then only tasks of
that work queue MUST be returned.
If no status list has been specified then tasks in all
valid states are returned.
The where clause is optional. If specified, it MUST
reference exactly one column using the following operators: equals
(“=”), not equals (“<>”), less than (“<”), greater
than (“>”), less than or equals (“<=”), and greater than
or equals (“>=”), e.g., “Task.Priority = 1”).
The created-on clause is optional. The where clause is logically
ANDed with the created-on clause, which MUST reference the column
Task.CreatedTime with operators as described above.
The combination of the two clauses enables simple but restricted paging
in a task list client.
If maxTasks is specified, then the number of task
abstracts returned for this query MUST NOT exceed this limit. The
taskIndexOffset can be used to perform multiple identical queries and iterate
over result sets where the maxTasks size exceeds the query limit. If maxTasks
has not been specified then all tasks fulfilling the query are returned.
|
In
- task type (“ALL” | “TASKS” | “NOTIFICATIONS”)
- generic human role
- work queue
- status list
- where clause
- order-by clause
- created-on clause
- maxTasks
- taskIndexOffset
Out
- list of tasks (list of htt:tTaskAbstract)
|
Any
|
|
getMyTaskDetails
|
Retrieve the task details. This operation is used to
obtain the data required to display a task list, as well as the details for
the individual tasks.
If no task type has been
specified then the default value “ALL” MUST be used.
If no generic human role has been specified then the
default value “actualOwner” MUST be used.
If no work queue has been specified then only personal
tasks MUST be returned. If the work queue is specified then only tasks of
that work queue MUST be returned.
If no status list has been specified then tasks in all
valid states are returned.
The where clause is optional. If specified, it MUST
reference exactly one column using the following operators: equals
(“=”), not equals (“<>”), less than (“<”), greater
than (“>”), less than or equals (“<=”), and greater than
or equals (“>=”),e.g., “Task.Priority = 1”.
The created-on clause is optional. The where clause is logically
ANDed with the created-on clause, which MUST reference the column
Task.CreatedTime with operators as described above.
The combination of the two clauses enables simple but restricted paging
in the task list client.
If maxTasks is specified, then the number of task details
returned for this query MUST NOT exceed this limit. If maxTasks has not been
specified then all tasks fulfilling the query are returned.
|
In
- task type (“ALL” | “TASKS” | “NOTIFICATIONS”)
- generic human role
- work queue
- status list
- where clause
- created-on clause
- maxTasks
Out
- list of tasks (list of htt:tTaskDetails)
|
Any
|
The return types tTaskAbstract
and tTaskDetails are defined in
section 3.8.4 “Data Types for Task Instance Data”.
Simple
Task View
The table below lists the task attributes available to the
simple query operations. This view is used when defining the where clause of
any of the above query operations.
|
Column Name
|
Type
|
|
ID
|
xsd:string
|
|
TaskType
|
Enumeration
|
|
Name
|
xsd:QName
|
|
Status
|
Enumeration (for values see 4.10 “Human Task Behavior and
State Transitions”)
|
|
Priority
|
htt:tPriority
|
|
CreatedTime
|
xsd:dateTime
|
|
ActivationTime
|
xsd:dateTime
|
|
ExpirationTime
|
xsd:dateTime
|
|
HasPotentialOwners
|
xsd:boolean
|
|
StartByTimeExists
|
xsd:boolean
|
|
CompleteByTimeExists
|
xsd:boolean
|
|
RenderingMethodExists
|
xsd:boolean
|
|
Escalated
|
xsd:boolean
|
|
ParentTaskId
|
xsd:string
|
|
HasSubTasks
|
xsd:boolean
|
|
SearchBy
|
xsd:string
|
|
Outcome
|
xsd:string
|
The advanced query operation is used by the task list client
to perform queries not covered by the simple query operations defined in 7.1.2. A WS-HumanTask Processor MAY support this operation. An implementation MAY
restrict the results according to authorization of the invoking user.
The following operations will return both matching tasks and
sub tasks.
|
Operation Name
|
Description
|
Parameters
|
|
query
|
Retrieve task data. All clauses assume a (pseudo-) SQL
syntax. If maxTasks is specified, then the number of task returned by the
query MUST NOT exceed this limit. The taskIndexOffset can be used to perform
multiple identical queries and iterate over result sets where the maxTasks
size exceeds the query limit.
|
In
- select clause
- where clause
- order-by clause
- maxTasks
- taskIndexOffset
Out
- task query result set (htt:tTaskQueryResultSet)
|
ResultSet
Data Type
This is the result set element that is returned by the query operation.
<xsd:element name="taskQueryResultSet" type="tTaskQueryResultSet" />
<xsd:complexType name="tTaskQueryResultSet">
<xsd:sequence>
<xsd:element name="row" type="tTaskQueryResultRow"
minOccurs="0" maxOccurs="unbounded"
/>
</xsd:sequence>
</xsd:complexType>
The following is the type of the row element contained in
the result set. The value in the row are returned in the same order as
specified in the select clause of the query.
<xsd:complexType name="tTaskQueryResultRow">
<xsd:choice minOccurs="0"
maxOccurs="unbounded">
<xsd:element name="id" type="xsd:stringanyURI"/>
<xsd:element name="taskType" type="xsd:string"/>
<xsd:element name="name" type="xsd:QName"/>
<xsd:element name="status" type="tStatus"/>
<xsd:element name="priority" type="htt:tPriority"/>
<xsd:element name="taskInitiator"
type="htt:tUser"/>
<xsd:element name="taskStakeholders"
type="htt:tOrganizationalEntity"/>
<xsd:element name="potentialOwners"
type="htt:tOrganizationalEntity"/>
<xsd:element name="businessAdministrators"
type="htt:tOrganizationalEntity"/>
<xsd:element name="actualOwner" type="htt:tUser"/>
<xsd:element name="notificationRecipients"
type="htt:tOrganizationalEntity"/>
<xsd:element name="createdTime" type="xsd:dateTime"/>
<xsd:element name="createdBy" type="xsd:string"/>
<xsd:element name="lastModifiedTime" type="xsd:dateTime"/>
<xsd:element name="lastModifiedBy" type="xsd:string"/>
<xsd:element name="activationTime" type="xsd:dateTime"/>
<xsd:element name="expirationTime" type="xsd:dateTime"/>
<xsd:element name="isSkipable" type="xsd:boolean"/>
<xsd:element name="hasPotentialOwners" type="xsd:boolean"/>
<xsd:element name="startByTime" type="xsd:dateTime"/>
<xsd:element name="completeByTime" type="xsd:dateTime"/>
<xsd:element name="presentationName" type="tPresentationName"/>
<xsd:element name="presentationSubject"
type="tPresentationSubject"/>
<xsd:element name="renderingMethodName"
type="xsd:QName"/>
<xsd:element name="hasOutput" type="xsd:boolean"/>
<xsd:element name="hasFault" type="xsd:boolean"/>
<xsd:element name="hasAttachments" type="xsd:boolean"/>
<xsd:element name="hasComments" type="xsd:boolean"/>
<xsd:element name="escalated" type="xsd:boolean"/>
<xsd:element name="parentTaskId" type="xsd:stringanyURI"/>
<xsd:element name="hasSubTasks" type="xsd:boolean"/>
<xsd:element name="searchBy" type="xsd:string"/>
<xsd:element name="outcome" type="xsd:string"/>
<xsd:element name="taskOperations" type="tTaskOperations"/>
<xsd:any namespace="##other"
processContents="lax"/>
</xsd:choice>
</xsd:complexType>
Complete
Task View
The table below is the set of columns used when defining
select clause, where clause, and order-by clause of query operations.
Conceptually, this set of columns defines a universal relation. As a result the
query can be formulated without specifying a from clause. A WS-HumanTask
Processor MAY extend this view by adding columns.
|
Column Name
|
Type
|
Constraints
|
|
ID
|
xsd:string
|
|
|
TaskType
|
Enumeration
|
Identifies the task type. The following values are
allowed:
- “TASK” for a human task
- “NOTIFICATION” for notifications
Note that notifications are simple tasks that do not block
the progress of the caller,
|
|
Name
|
xsd:QName
|
|
|
Status
|
Enumeration
|
For values see section 4.10 “Human Task Behavior and State
Transitions”
|
|
Priority
|
htt:tPriority
|
|
|
(GenericHumanRole)
|
xsd:tUser
or
htt:tOrganizationalEntity
|
|
|
CreatedTime
|
xsd:dateTime
|
The time in UTC when the task has been created.
|
|
CreatedBy
|
xsd:string
|
|
|
LastModifiedTime
|
xsd:dateTime
|
The time in UTC when the task has been last modified.
|
|
LastModifiedBy
|
xsd:string
|
|
|
ActivationTime
|
xsd:dateTime
|
The time in UTC when the task has been activated.
|
|
ExpirationTime
|
xsd:dateTime
|
The time in UTC when the task will expire.
|
|
IsSkipable
|
xsd:boolean
|
|
|
StartByTime
|
xsd:dateTime
|
The time in UTC when the task needs to be started. This
time corresponds to the respective start deadline.
|
|
CompleteByTime
|
xsd:dateTime
|
The time in UTC when the task needs to be completed. This
time corresponds to the respective end deadline.
|
|
PresentationName
|
xsd:string
|
The task’s presentation name.
|
|
PresentationSubject
|
xsd:string
|
The task’s presentation subject.
|
|
RenderingMethodName
|
xsd:QName
|
The task’s rendering method name.
|
|
HasOutput
|
xsd:boolean
|
|
|
HasFault
|
xsd:boolean
|
|
|
HasAttachments
|
