Designing business processes in Business Central

Red Hat Process Automation Manager 7.5

Red Hat Customer Content Services

Abstract

This document describes concepts and options for designing business processes in Red Hat Process Automation Manager 7.5.

Preface

As a business processes developer, you can use Business Central in Red Hat Process Automation Manager to design business processes to meet specific business requirements. This document describes business processes and the concepts and options for creating them using the process designer in Red Hat Process Automation Manager. This document also describes the BPMN2 elements in Red Hat Process Automation Manager. For more details about BPMN2, see the Business Process Model and Notation Version 2.0 specification.

Prerequisites

Chapter 1. Business processes

A business process is a diagram that describes the order for a series of steps that must be executed and consists of predefined nodes and connections. Each node represents one step in the process while the connections specify how to transition from one node to another.

A typical business process consists of the following components:

  • The header section that comprises global elements such as the name of the process, imports, and variables
  • The nodes section that contains all the different nodes that are part of the process
  • The connections section that links these nodes to each other to create a flow chart

Figure 1.1. Business process

This image shows the steps of "self evaluation" through the project manager and HR manager.

Red Hat Process Automation Manager contains the legacy process designer and the new process designer for creating business process diagrams. The new process designer has an improved layout and feature set and continues to be developed. Until all features of the legacy process designer are completely implemented in the new process designer, both designers are available in Business Central for you to use.

Note

The legacy process designer in Business Central is deprecated in Red Hat Process Automation Manager 7.5.1. It will be removed in a future Red Hat Process Automation Manager release. The legacy process designer will not receive any new enhancements or features. If you intend to use the new process designer, start migrating your processes to the new designer. Create all new processes in the new process designer. For information about migrating to the new designer, see Managing projects in Business Central.

Chapter 2. Business Process Modeling and Notation Version 2.0

The Business Process Modeling and Notation Version 2.0 (BPMN2) specification is an Object Management Group (OMG) specification that defines standards for graphically representing a business process, defines execution semantics for the elements, and provides process definitions in XML format.

A process is defined or determined by its process definition. It exists in a knowledge base and is identified by its ID. A process is a container for a set of modeling elements. It contains elements that specify the execution workflow of a business process or its parts using flow objects and flows. Each process has its own BPMN2 diagram. Red Hat Process Automation Manager contains the legacy process designer and the new process designer for creating BPMN2 diagrams. The new process designer has an improved layout and feature set and continues to be developed. Until all features of the legacy process designer are completely implemented in the new process designer, both designers are available in Business Central for you to use.

Chapter 3. Red Hat Process Automation Manager support for BPMN2

With Red Hat Process Automation Manager, you can model your business processes using the BPMN 2.0 standard. You can then use Red Hat Process Automation Manager to run, manage, and monitor these business processes. The full BPMN 2.0 specification also includes details on how to represent items such as choreographies and collaboration. However, Red Hat Process Automation Manager uses only the parts of the specification that you can use to specify executable processes. This includes almost all elements and attributes as defined in the Common Executable subclass of the BPMN2 specification, extended with some additional elements and attributes.

The following table contains a list of icons used to indicate whether a BPMN2 element is supported in the legacy process designer, the legacy and new process designer, or not supported.

Table 3.1. Support status icons

KeyDescription

grn check

Supported in the legacy and new process designer

grn star

Supported in the legacy process designer only

bk x

Not supported

Elements that have no icon do not exist in the BPMN2 specification.

Table 3.2. BPMN2 catching events

Element NameStartIntermediate

None

grn check

 

Message

grn check

grn check

Timer

grn check

grn check

Error

grn check

grn check

Escalation

grn check

grn check

Cancel

 

bk x

Compensation

grn check

grn check

Conditional

grn check

grn check

Link

 

bk x

Signal

grn check

grn check

Multiple

bk x

bk x

Parallel Multiple

bk x

bk x

Table 3.3. BPMN2 throwing and non-interrupting events

Element NameThrowing Non-interrupting 
 

End

Intermediate

Start

Intermediate

None

grn check

   

Message

grn check

grn check

grn check

grn check

Timer

  

grn check

grn check

Error

grn check

   

Escalation

grn check

grn check

grn check

grn check

Cancel

bk x

bk x

 

bk x

Compensation

grn check

grn check

  

Conditional

  

grn check

grn check

Link

 

bk x

  

Signal

grn check

grn check

grn check

grn check

Terminate

grn check

   

Multiple

bk x

bk x

bk x

bk x

Parallel Multiple

  

bk x

bk x

Table 3.4. BPMN2 elements

Element typeElementSupported

Task

Business rule

grn check

 

Script

grn check

 

User task

grn check

 

Service task

grn check

Subprocesses

Embedded

grn check

 

Ad hoc

grn check

 

Reusable

grn check

 

Event

grn check

Gateways

Inclusive

grn check

 

Exclusive

grn check

 

Parallel

grn check

 

Event-based

grn check

 

Complex

bk x

Connecting objects

Sequence flows

grn check

 

Association flows

grn check

Swimlanes

Swimlanes

grn check

Artifacts

Group

grn star

 

Text annotation

grn check

For more information about the background and applications of BPMN2, see the OMG Business Process Model and Notation (BPMN) Version 2.0 specification.

3.1. BPMN2 events in process designer

An event is something that happens to a business process. BPMN2 supports three categories of events:

  • Start
  • End
  • Intermediate

Within these categories, events are differentiated as either catching an event trigger or throwing an event result.

The following business process diagram shows examples of events: events

In this example, the following events occurred:

  • The ATM Card Inserted signal start event is triggered when the signal is received.
  • The timeout intermediate event is an interrupting event based on a timer trigger. This means that the Wait for PIN subprocess is canceled when the timer event is triggered.
  • The normal (none) end event ends the process.

3.1.1. Start events

Use start events to indicate the start of a business process. A start event cannot have an incoming sequence flow and must have only one outgoing sequence flow. You can use none start events in top-level processes, embedded subprocess, callable subprocesses, and event subprocesses.

All start events, with the exception of the none start event, are catch events. For example, a signal start event starts the process only when the referenced signal (event trigger) is received. You can configure start events in event subprocesses to be interrupting or non-interrupting. An interrupting start event for an event subprocess stops or interrupts the execution of the containing or parent process. A non-interrupting start event does not stop or interrupt the execution of the containing or parent process.

Table 3.5. Start events

Start event typeTop-levelSubprocesses 
  

Interrupt

Non-interrupt

None

bpmn start node

  

Conditional

bpmn conditional start

bpmn conditional start

bpmn conditional non interrupt

Compensation

bpmn compensation start

bpmn compensation start

 

Error

 

bpmn error start

 

Escalation

bpmn escalation start

bpmn escalation start

bpmn escalation non interrupt

Message

bpmn message node

bpmn message node

bpmn message non interrupt

Signal

bpmn signal start

bpmn signal start

bpmn signal non interrupt

Timer

bpmn timer start

bpmn timer start

bpmn timer non interrupt

None

The none start event is a start event without a trigger condition. A process or a subprocess can contain at most one none start event, which is triggered on process or subprocess start by default, and the outgoing flow is taken immediately.

When you use a none start event in a subprocess, the execution of the process flow is transferred from the parent process into the subprocess and the none start event is triggered. This means that the token (the current location within the process flow) is passed from the parent process into the subprocess activity and the none start event of the subprocess generates a token of its own.

Conditional

The conditional start event is a start event with a Boolean condition definition. The execution is triggered when the condition is first evaluated to false and then to true. The process execution starts only if the condition is evaluated to true after the start event has been instantiated.

A process can contain multiple conditional start events.

Compensation

A compensation start event is used to start a compensation event subprocess when using a subprocess as the target activity of a compensation intermediate event.

Error

A process or subprocess can contain multiple error start events, which are triggered when an error object with a particular ErrorRef property is received. The error object can be produced by an error end event. It indicates an incorrect process ending. The process instance with the error start event starts execution after it has received the respective error object. The error start event is executed immediately upon receiving the error object and its outgoing flow is taken.

Escalation

The escalation start event is a start event that is triggered by an escalation with a particular escalation code. Processes can contain multiple escalation start events. The process instance with an escalation start event starts its execution when it receives the defined escalation object. The process is instantiated and the escalation start event is executed immediately and its outgoing flow is taken.

Message

A process or an event subprocess can contain multiple message start events, which are triggered by a particular message. The process instance with a message start event only starts its execution from this event after it has received the respective message. After the message is received, the process is instantiated and its message start event is executed immediately (its outgoing flow is taken).

Because a message can be consumed by an arbitrary number of processes and process elements, including no elements, one message can trigger multiple message start events and therefore instantiate multiple processes.

Signal

The signal start event is triggered by a signal with a particular signal code. A process can contain multiple signal start events. The signal start event only starts its execution within the process instance after the instance has received the respective signal. Then, the signal start event is executed and its outgoing flow is taken.

Timer

The timer start event is a start event with a timing mechanism. A process can contain multiple timer start events, which are triggered at the start of the process, after which the timing mechanism is applied.

When you use a timer start event in a subprocess, execution of the process flow is transferred from the parent process into the subprocess and the timer start event is triggered. The token is taken from the parent subprocess activity and the timer start event of the subprocess is triggered and waits for the timer to trigger. After the time defined by the timing definition has been reached, the outgoing flow is taken.

3.1.2. Intermediate events

Intermediate events drive the flow of a business process. Intermediate events are used to either catch or throw an event during the execution of the business process. These events are placed between the start and end events and can also be used on the boundary of an activity, like a subprocess or a human task, as a catch event. The boundary catch events can be configured as interrupting or non-interrupting. An interrupting boundary catch event cancels the bound activity whereas a non-interrupting event does not.

An intermediate event handles a particular situation that occurs during process execution. The situation is a trigger for an intermediate event. In a process, intermediate events with one outgoing flow can be placed on an activity boundary.

If the event occurs while the activity is being executed, the event triggers its execution to the outgoing flow. One activity may have multiple boundary intermediate events. Note that depending on the behavior you require from the activity with the boundary intermediate event, you can use either of the following intermediate event types:

  • Interrupting: The activity execution is interrupted and the execution of the intermediate event is triggered.
  • Non-interrupting: The intermediate event is triggered and the activity execution continues.

Table 3.6. Intermediate events

Intermediate event typeCatchingBoundary Throwing
  

Interrupt

Non-interrupt

 

Message

bpmn intermediate message

bpmn intermediate message

bpmn message noninterrupt

bpmn message throwing

Timer

bpmn intermediate timer

bpmn intermediate timer

bpmn timer noninterrupt

 

Error

 

bpmn intermediate error

  

Signal

bpmn intermediate signal

bpmn intermediate signal

bpmn signal noninterrupt

bpmn signal throwing

Conditional

bpmn intermediate conditional

bpmn intermediate conditional

bpmn conditional noninterrupt

 

Compensation

bpmn intermediate catch

bpmn intermediate catch

 

bpmn intermediate compensation throwing

Escalation

bpmn intermediate escalation

bpmn intermediate escalation

 

bpmn intermediate escalation throwing

Message

A message intermediate event is an intermediate event that enables you to manage a message object. Use one of the following events:

  • A throwing message intermediate event produces a message object based on the defined properties.
  • A catching message intermediate event listens for a message object with the defined properties.

Timer

A timer intermediate event enables you to delay workflow execution or to trigger the workflow execution periodically. It represents a timer that can trigger one or multiple times after a specified period of time. When the timer intermediate event is triggered, the timer condition, which is the defined time, is checked and the outgoing flow is taken. When the timer intermediate event is placed in the process workflow, it has one incoming flow and one outgoing flow. Its execution starts when the incoming flow transfers to the event. When a timer intermediate event is placed on an activity boundary, the execution is triggered at the same time as the activity execution.

The timer is canceled if the timer element is canceled, for example by completing or aborting the enclosing process instance.

Conditional

A conditional intermediate event is an intermediate event with a boolean condition as its trigger. The event triggers further workflow execution when the condition evaluates to true and its outgoing flow is taken.

The event must define the Expression property. When a conditional intermediate event is placed in the process workflow, it has one incoming flow, one outgoing flow, and its execution starts when the incoming flow transfers to the event. When a conditional intermediate event is placed on an activity boundary, the execution is triggered at the same time as the activity execution. Note that if the event is non-interrupting, the event triggers continuously while the condition is true.

Signal

A signal intermediate event enables you to produce or consume a signal object. Use either of the following options:

  • A throwing signal intermediate event produces a signal object based on the defined properties.
  • A catching signal intermediate event listens for a signal object with the defined properties.

Error

An error intermediate event is an intermediate event that can be used only on an activity boundary. It enables the process to react to an error end event in the respective activity. The activity must not be atomic. When the activity finishes with an error end event that produces an error object with the respective ErrorCode property, the error intermediate event catches the error object and execution continues to its outgoing flow.

Compensation

A compensation intermediate event is a boundary event attached to an activity in a transaction subprocess. It can finish with a compensation end event or a cancel end event. The compensation intermediate event must be associated with a flow, which is connected to the compensation activity.

The activity associated with the boundary compensation intermediate event is executed if the transaction subprocess finishes with the compensation end event. The execution continues with the respective flow.

Escalation

An escalation intermediate event is an intermediate event that enables you to produce or consume an escalation object. Depending on the action the event element should perform, you need to use either of the following options:

  • A throwing escalation intermediate event produces an escalation object based on the defined properties.
  • A catching escalation intermediate event listens for an escalation object with the defined properties.

3.1.3. End events

End events are used to end a business process and may not have any outgoing sequence flows. There may be multiple end events in a business process. All end events, with the exception of the none and terminate end events, are throw events.

End events indicate the completion of a business process. An end event is a node that ends a particular workflow. It has one or more incoming sequence flows and no outgoing flow.

A process must contain at least one end event.

During run time, an end event finishes the process workflow. The end event can finish only the workflow that reached it, or all workflows in the process instance, depending on the end event type.

Table 3.7. End events

None

The none end event specifies that no other special behavior is associated with the end of the process.

Message

When a flow enters a message end event, the flow finishes and the end event produces a message as defined in its properties.

Signal

A throwing signal end event is used to finish a process or subprocess flow. When the execution flow enters the element, the execution flow finishes and produces a signal identified by its SignalRef property.

Error

The throwing error end event finishes the incoming workflow, which means consumes the incoming token, and produces an error object. Any other running workflows in the process or subprocess remain uninfluenced.

Compensation

A compensation end event is used to finish a transaction subprocess and trigger the compensation defined by the compensation intermediate event attached to the boundary of the subprocess activities.

Escalation

The escalation end event finishes the incoming workflow, which means consumes the incoming token, and produces an escalation signal as defined in its properties, triggering the escalation process.

Terminate

The terminate end event finishes all execution flows in the specified process instance. Activities being executed are canceled. If a terminate end event is reached in a subprocess, the entire process instance is terminated.

3.2. BPMN2 tasks in process designer

A task is an automatic activity that is defined in the process model and the smallest unit of work in a process flow. The following task types defined in the BPMN2 specification are available in the Red Hat Process Automation Manager process designer palette:

  • Business rule tasks: Used to make decisions through a Decision Model and Notation (DMN) model or rule flow group
  • Script tasks: Used to execute a piece of code written in Java, JavaScript, or MVEL
  • User tasks: Used to include human actions as input to the business process

Table 3.8. Task

Business rule task

bpmn business rule task

Script task

bpmn script task

User task

bpmn user task

Service task

bpmn service task

None task

bpmn none task

In addition, the BPMN2 specification provides the ability to create custom tasks. The following predefined custom tasks are included with Red Hat Process Automation Manager:

  • Rest service tasks: Used to invoke a remote RESTful service
  • Email service tasks: Used to send an email
  • Log service tasks: Used to log a message
  • Java service tasks: Used to call Java code
  • WebService service tasks: Used to invoke a remote WebService call
  • DecisionTask tasks: Used to execute a DMN diagram

Business rule task

A business rule task defines a way to make a decision either through a DMN model or a rule flow group.

bpmn business rule task

When a process reaches a business rule task defined by a DMN model, the process engine executes the DMN model decision with the inputs provided.

When a process reaches a business rule task defined by a rule flow group, the process engine begins executing the rules in the defined rule flow group. When there are no more active rules in the rule flow group, the execution continues to the next element. During the rule flow group execution, new activations belonging to the active rule flow group can be added to the agenda because these activations are changed by other rules.

Script task

A script task represents a script to be executed during the process execution.

bpmn script task

The associated script can access process variables and global variables. Review the following list before using a script task:

  • Avoid low-level implementation details in the process. A script task can be used to manipulate variables, but consider using a service task when modelling more complex operations.
  • Ensure that the script is executed immediately, otherwise use an asynchronous service task.
  • Avoid contacting external services through a script task. Use a service task to model communication with an external service.
  • Ensure scripts do not throw exceptions. Runtime exceptions should be caught and managed, for example, inside the script or transformed into signals or errors that can then be handled inside the process.

When a script task is reached during execution, the script is executed and the outgoing flow is taken.

User task

User tasks are tasks in the process workflow that cannot be performed automatically by the system and therefore require the intervention of a human user, the actor.

bpmn user task

On execution, the User task element is instantiated as a task that appears in the list of tasks of one or more actors. If a User task element defines the Groups attribute, it is displayed in task lists of all users that are members of the group. Any user who is a member of the group can claim the task.

After it is claimed, the task disappears from the task list of the other users.

User tasks are implemented as domain-specific tasks and serve as a base for custom tasks.

Service task

Service tasks are tasks that do not require human interaction. They are completed automatically,by an external software service.

bpmn service task

None task

None tasks are completed on activation. This is a conceptual model only. A none task is never actually executed by an IT system.

bpmn none task

3.3. BPMN2 subprocesses in process designer

A subprocess is an activity that contains nodes. You can embed part of the main process within a subprocess. You can also include variable definitions within the subprocess. These variables are accessible to all nodes inside the subprocess.

A subprocess must have one incoming connection and one outgoing connection. If you use a terminate end event inside a subprocess, the entire process instance that contains the subprocess is terminated, not just the subprocess. A subprocess ends when there are no more active elements in it.

The following subprocess types are supported in Red Hat Process Automation Manager:

  • Embedded subprocess, which is a part of the parent process execution and shares its data
  • ad hoc subprocess, which has no strict element execution order
  • Reusable subprocess, which is independent from its parent process
  • Event subprocess, which is only triggered on a start event or a timer
  • Multi-instance subprocess

In the following example, the Place Order subprocess checks whether sufficient stock is available to place the order and updates the stock information if the order can be placed. The customer is then notified through the main process based on whether or not the order was placed.

subprocess

Embedded subprocess

An embedded subprocess encapsulates a part of the process. It must contain a start event and at least one end event. Note that the element enables you to define local subprocess variables that are accessible to all elements inside this container.

AdHoc subprocess

An ad hoc subprocess or process contains a number of embedded inner activities and is intended to be executed with a more flexible ordering compared to the typical routing of processes. Unlike regular processes, an ad hoc subprocess does not contain a complete, structured BPMN2 diagram description, for example, from start event to end event. Instead, the ad hoc subprocess contains only activities, sequence flows, gateways, and intermediate events. An ad hoc subprocess can also contain data objects and data associations. The activities within the ad hoc subprocesses are not required to have incoming and outgoing sequence flows. However, you can specify sequence flows between some of the contained activities. When used, sequence flows provide the same ordering constraints as in a regular process. To have any meaning, intermediate events must have outgoing sequence flows and they can be triggered multiple times while the ad hoc subprocess is active.

Reusable subprocess

Reusable subprocesses appear collapsed within the containing process, and the subprocesses elements are not visible until you click a plus sign at the lower edge of the rounded rectangle.

Event subprocess

An event subprocess becomes active when its start event is triggered. It can interrupt the parent process context or run in parallel with it.

With no outgoing or incoming connections, only an event or a timer can trigger the subprocess. The subprocess is not part of the regular control flow. Although self-contained, it is executed in the context of the bounding process.

Use an event subprocess within a process flow to handle events that happen outside of the main process flow. For example, while booking a flight, two events may occur:

  • Cancel booking (interrupting)
  • Check booking status (non-interrupting)

You can model both of these events using the event subprocess.

Multiple instance subprocess

A multiple instances subprocess is instantiated multiple times when its execution is triggered. The instances are created sequentially. A new subprocess instance is created only after the previous instance has finished.

A multiple instances subprocess has one incoming connection and one outgoing connection.

3.4. BPMN2 gateways in process designer

Gateways are used to create or synchronize branches in the workflow using a set of conditions called the gating mechanism. BPMN2 supports two types of gateways:

  • Converging gateways, merging multiple flows into one flow
  • Diverging gateways, splitting one flow into multiple flows

One gateway cannot have multiple incoming and multiple outgoing flows.

In the following business process diagram, the XOR gateway evaluates only the incoming flow whose condition evaluates to true: gateway

In this example, the customer details are verified by a user and the process is assigned to a user for approval. If approved, an approval notification is sent to the user. If the event of the request is rejected, a rejection notification is sent to the user.

Table 3.9. Gateway elements

Element typeIcon

exclusive (XOR)

bpmn gateway exclusive

Inclusive

bpmn gateway inclusive

Parallel

bpmn gateway parallel

Event

bpmn gateway event

Exclusive

In an exclusive diverging gateway, only the first incoming flow whose condition evaluates to true is chosen. In a converging gateway, the next node is triggered for each triggered incoming flow.

The gateway triggers exactly one outgoing flow. The flow with the constraint evaluated to true and the lowest priority number is taken.

Important

Ensure that at least one of the outgoing flows evaluates to true at run time. Otherwise, the process instance terminates with a runtime exception.

The converging gateway enables a workflow branch to continue to its outgoing flow as soon as it reaches the gateway. When one of the incoming flows triggers the gateway, the workflow continues to the outgoing flow of the gateway. If it is triggered from more than one incoming flow, it triggers the next node for each trigger.

Inclusive

With an inclusive diverging gateway, the incoming flow is taken and all outgoing flows that evaluate to true are taken. Connections with lower priority numbers are triggered before triggering higher priority connections. Priorities are evaluated but the BPMN2 specification does not guarantee the priority order. Avoid depending on the priority attribute in your workflow.

Important

Ensure that at least one of the outgoing flows evaluates to true at run time. Otherwise, the process instance terminates with a runtime exception.

A converging inclusive gateway merges all incoming flows previously created by an inclusive diverging gateway. It acts as a synchronizing entry point for the inclusive gateway branches.

Parallel

Use a parallel gateway to synchronize and create parallel flows. With a parallel diverging gateway, the incoming flow is taken, all outgoing flows are taken simultaneously. With a converging parallel gateway, the gateway waits until all incoming flows have entered and only then triggers the outgoing flow.

Event

An event-based gateway is only diverging and enables you to react to possible events as opposed to the data-based exclusive gateway, which reacts to the process data. The outgoing flow is taken based on the event that occurs. Only one outgoing flow is taken at a time. The gateway might act as a start event, where the process is instantiated only if one of the intermediate events connected to the event-based gateway occurs.

3.5. BPMN2 connecting objects in process designer

Connecting objects create an association between two BPMN2 elements. When a connecting object is directed, the association is sequential and indicates that one of the elements is executed immediately before the other, within an instance of the process. Connecting objects can start and end at the top, bottom, right, or left of the process elements being associated. The OMG BPMN2 specification allows you to use your discretion, placing connecting objects in a way that makes the process behavior easy to understand and follow.

BPMN2 supports two main types of connecting objects:

  • Sequence flows: Connect elements of a process and define the order in which those elements are executed within an instance.
  • Association flows: Connect the elements of a process without execution semantics. Association flows can be undirected or unidirectional.
Note

The new process designer supports only undirected association flows. The legacy designer supports one direction and Unidirection flows.

3.6. BPMN2 swimlanes in process designer

Swimlanes are process elements that visually group tasks related to one group or user. You can use user tasks in combination with swimlanes to assign multiple human tasks to the same actor. At run time, swimlanes auto-claim or assign tasks to users who have completed another task in that lane, within the same process instance. When the first task in a swimlane is created, and that task has an actor ID specified, that actor ID is assigned to all other tasks of that swimlane as well. A lane is a sub-partition within a process that enables you to group some process elements and define their common parameters.

In the following example, the Analyst lane has two user tasks: swimlane

The Group field in the Update Customer Details and Resolve Customer Issue tasks has the value analyst. When the process is started, and the Update Customer Details task is claimed, started, or completed by an analyst user, the Resolve Customer Issue task is claimed and assigned to the user who completed the first task. However, if only the Update Customer Details task has the analyst group assigned, and the second task had no user or group assignments, the process stops after the first task completes.

Chapter 4. Creating a business process in Business Central

The process designer is the Red Hat Process Automation Manager process modeler. The output of the modeler is a BPMN 2.0 process definition file. The definition is used as input for the Red Hat Process Automation Manager process engine, which creates a process instance based on the definition.

The procedures in this section provide a general overview of how to create a simple business process. For a more detailed business process example, see Getting started with business processes.

Prerequisites

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project name to open the project’s asset list.
  3. Click Add Asset → Business Process.
  4. In the Create new Business Process wizard, enter the following values:

    • Business Process: New business process name
    • Package: Package location for your new business process, for example com.myspace.myProject
  5. Click Ok to open the process designer.
  6. In the upper-right corner, click the Diagram properties diagram properties icon and add your business process property information, such as process data and variables:

    1. Scroll down and expand Process Data.
    2. Click btn plus next to Process Variables and define the process variables that you want to use in your business process.
  7. In the process designer canvas, use the left toolbar to drag and drop BPMN components to define your business process logic, connections, events, tasks, or other elements.
  8. After you add and define all components of the business process, click Save to save the completed business process.

4.1. Creating business process tasks

You can create the following types of tasks as part of your business process:

  • Business rule tasks: Used to make decisions through a Decision Model and Notation (DMN) model or rule flow group
  • Script tasks: Used to execute a piece of code written in Java, JavaScript, or MVEL
  • User tasks: Used to include human actions as input to the business process

As an example, this procedure uses a user task.

Procedure

  1. Click the start event to create an outgoing connection to a new task.

    Figure 4.1. Outgoing connection from the start event to a user task

    Creating an outgoing connection from the start event to a user task
  2. Convert the new task to one of the available task types, such as a user task.

    Figure 4.2. Convert into a User task

    Converting in to a user task
  3. For this example, click the user task and in the upper-right corner, click the Diagram properties diagram properties icon.
  4. Add the user task property information, such as the following details:

    1. Expand Implementation/Execution and enter values for both the Task Name and Actor fields.
    2. Click btn assign next to Assignments to open the Data I/O window
    3. Create the input and output assignments for the user task.
  5. After you add and define all task information, click Save to save the updated business process.

4.2. Making a copy of a business process

You can make a copy of a business process in Business Central and modify the copied process as needed.

Procedure

  1. In the business process designer, click Copy in the upper-right toolbar.
  2. In the Make a Copy window, enter a new name for the copied business process, select the target package, and optionally add a comment.
  3. Click Make a Copy.
  4. Modify the copied business process as needed and click Save to save the updated business process.

4.3. Resizing elements and using the zoom function to view business processes

You can resize individual elements in a business process and zoom in or out to modify the view of your business process.

Procedure

  1. In the business process designer, select the element and click the red dot in the lower-right corner of the element.
  2. Drag the red dot to resize the element.

    Figure 4.3. Resize an element

    Resizing an element
  3. To zoom in or out to view the entire diagram, click the plus or minus sign on the lower-right side of the canvas.

    Figure 4.4. Enlarge or shrink a business process

    Zooming to view the entire diagram

4.4. Generating process documentation in Business Central

In the process designer in Business Central, you can view and print a report of the process definition. The process documentation summarizes the components, data, and visual flow of the process in a format (PDF) that you can print and share more easily.

Procedure

  1. In Business Central, navigate to a project that contains a business process and select the process.
  2. In the process designer, click the Documentation tab to view the summary of the process file, and click Print in the top-right corner of the window to print the PDF report.

    Figure 4.5. Generate process documentation

    Project-level service task settings

Chapter 5. Deploying a business process in Business Central

After you design your business process in Business Central, you can build and deploy your project in Business Central to make the process available to Process Server.

Prerequisites

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project that you want to deploy.
  3. Click Deploy.

    Note

    You can also select the Build & Install option to build the project and publish the KJAR file to the configured Maven repository without deploying to a Process Server. In a development environment, you can click Deploy to deploy the built KJAR file to a Process Server without stopping any running instances (if applicable), or click Redeploy to deploy the built KJAR file and replace all instances. The next time you deploy or redeploy the built KJAR, the previous deployment unit (KIE container) is automatically updated in the same target Process Server. In a production environment, the Redeploy option is disabled and you can click Deploy only to deploy the built KJAR file to a new deployment unit (KIE container) on a Process Server.

    To configure the Process Server environment mode, set the org.kie.server.mode system property to org.kie.server.mode=development or org.kie.server.mode=production. To configure the deployment behavior for a corresponding project in Business Central, go to project SettingsGeneral SettingsVersion and toggle the Development Mode option. By default, Process Server and all new projects in Business Central are in development mode. You cannot deploy a project with Development Mode turned on or with a manually added SNAPSHOT version suffix to a Process Server that is in production mode.

Chapter 6. Executing a business process in Business Central

After you build and deploy the project that contains your business process, you can execute the defined functionality for the business process.

As an example, this procedure uses the Mortgage_Process sample project in Business Central. In this scenario, you input data into a mortgage application form acting as the mortgage broker. The MortgageApprovalProcess business process runs and determines whether or not the applicant has offered an acceptable down payment based on the decision rules defined in the project. The business process either ends the rule testing or requests that the applicant increase the down payment to proceed. If the application passes the business rule testing, the bank approver reviews the application and either approves or denies the loan.

Prerequisites

  • Process Server is deployed and connected to Business Central. For more information about Process Server configuration, see Installing and configuring Red Hat Process Automation Manager on Red Hat JBoss EAP 7.2.
  • You have imported the Mortgage_Process sample project in Business Central. (Go to MenuDesignProjects, click dots in the upper-right corner of the screen, and select Try SamplesMortgage_ProcessOk.)
  • You have built and deployed the Mortgage_Process sample project.

Procedure

  1. In Business Central, go to MenuManageProcess Definitions.
  2. Click anywhere in the MortgageApprovalProcess row to view the process details.
  3. Click the Diagram tab to view the business process diagram in the editor.
  4. Click New Process Instance to open the Application form and input the following values into the form fields:

    • Down Payment: 30000
    • Years of amortization: 10
    • Name: Ivo
    • Annual Income: 60000
    • SSN: 123456789
    • Age of property: 8
    • Address of property: Brno
    • Locale: Rural
    • Property Sale Price: 50000
  5. Click Submit to start a new process instance. After starting the process instance, the Instance Details view opens.
  6. Click the Diagram tab to view the process flow within the process diagram. The state of the process is highlighted as it moves through each task.
  7. Click MenuManageTasks.

    For this example, the user or users working on the corresponding tasks are members of the following groups:

    • approver: For the Qualify task
    • broker: For the Correct Data and Increase Down Payment tasks
    • manager: For the Final Approval task
  8. As the approver, review the Qualify task information, click Claim and then Start to start the task, and then select Is mortgage application in limit? and click Complete to complete the task flow.
  9. In the Tasks page, click anywhere in the Final Approval row to open the Final Approval task.
  10. Click Claim to claim responsibility for the task, and click Complete to finalize the loan approval process.
Note

The Save and Release buttons are only used to either pause the approval process and save the instance if you are waiting on a field value, or to release the task for another user to modify.

Chapter 7. Process definitions and process instances in Business Central

A process definition is a Business Process Model and Notation (BPMN) 2.0 file that serves as a container for a process and its BPMN diagram. The process definition shows all of the available information about the business process, such as any associated subprocesses or the number of users and groups that are participating in the selected definition.

A process definition also defines the import entry for imported processes that the process definition uses, and the relationship entries.

BPMN2 source of a process definition

<definitions id="Definition"
               targetNamespace="http://www.jboss.org/drools"
               typeLanguage="http://www.java.com/javaTypes"
               expressionLanguage="http://www.mvel.org/2.0"
               xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"Rule Task
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xsi:schemaLocation="http://www.omg.org/spec/BPMN/20100524/MODEL BPMN20.xsd"
               xmlns:g="http://www.jboss.org/drools/flow/gpd"
               xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
               xmlns:dc="http://www.omg.org/spec/DD/20100524/DC"
               xmlns:di="http://www.omg.org/spec/DD/20100524/DI"
               xmlns:tns="http://www.jboss.org/drools">

    <process>
      PROCESS
    </process>

    <bpmndi:BPMNDiagram>
     BPMN DIAGRAM DEFINITION
    </bpmndi:BPMNDiagram>

    </definitions>

After you have created, configured, and deployed your project that includes your business processes, you can view the list of all the process definitions in Business Central MenuManageProcess Definitions. You can refresh the list of deployed process definitions at any time by clicking the refresh button in the upper-right corner.

The process definition list shows all the available process definitions that are deployed into the platform. Click any of the process definitions listed to show the corresponding process definition details. This displays information about the process definition, such as if there is a sub-process associated with it, or how many users and groups exist in the process definition. The Diagram tab in the process definition details page contains the BPMN2-based diagram of the process definition.

Within each selected process definition, you can start a new process instance for the process definition by clicking the New Process Instance button in the upper-right corner. Process instances that you start from the available process definitions are listed in MenuManageProcess Instances.

You can also define the default pagination option for all users under the Manage drop-down menu (Process Definition, Process Instances, Tasks, Execution Errors, and Jobs) and in MenuTrackTask Inbox.

For more information about process and task administration in Business Central, see Managing and monitoring business processes in Business Central.

7.1. Starting a process instance from the process definitions page

You can start a process instance in MenuManageProcess Definitions. This is useful for environments where you are working with several projects or process definitions at the same time.

Prerequisites

  • A project with a process definition has been deployed in Business Central.

Procedure

  1. In Business Central, go to MenuManageProcess Definitions.
  2. Select the process definition for which you want to start a new process instance from the list. The details page of the definition opens.
  3. Click the New Process Instance button in the upper-right corner to start a new process instance.
  4. Provide any required information for the process instance.
  5. Click Submit to create the process instance.
  6. View the new process instance in MenuManageProcess Instances.

7.2. Starting a process instance from the process instances page

You can create new process instances or view the list of all the running process instances in MenuManageProcess Instances.

Prerequisites

  • A project with a process definition has been deployed in Business Central.

Procedure

  1. In Business Central, go to MenuManageProcess Instances.
  2. Click the New Process Instance button in the upper-right corner and select the process definition for which you want to start a new process instance from the drop-down list.
  3. Provide any information required to start a new process instance.
  4. Click Start to create the process instance.

    The new process instance appears in the Manage Process Instances list.

7.3. Process definitions in XML

You can create processes directly in XML format using the BPMN 2.0 specifications. The syntax of these XML processes is defined using the BPMN 2.0 XML Schema Definition.

A process XML file consists of the following core sections:

  • process: This is the top part of the process XML that contains the definition of the different nodes and their properties. The process XML file consists of exactly one <process> element. This element contains parameters related to the process (its type, name, ID, and package name), and consists of three subsections: a header section where process-level information such as variables, globals, imports, and lanes are defined, a nodes section that defines each of the nodes in the process, and a connections section that contains the connections between all the nodes in the process.
  • BPMNDiagram: This is the lower part of the process XML file that contains all graphical information, such as the location of the nodes. The nodes section contains a specific element for each node and defines the various parameters and any sub-elements for that node type.

The following process XML file fragment shows a simple process that contains a sequence of a start event, a script task that prints "Hello World" to the console, and an end event:

<?xml version="1.0" encoding="UTF-8"?>

<definitions
  id="Definition"
  targetNamespace="http://www.jboss.org/drools"
  typeLanguage="http://www.java.com/javaTypes"
  expressionLanguage="http://www.mvel.org/2.0"
  xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.omg.org/spec/BPMN/20100524/MODEL BPMN20.xsd"
  xmlns:g="http://www.jboss.org/drools/flow/gpd"
  xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
  xmlns:dc="http://www.omg.org/spec/DD/20100524/DC"
  xmlns:di="http://www.omg.org/spec/DD/20100524/DI"
  xmlns:tns="http://www.jboss.org/drools">

  <process processType="Private" isExecutable="true" id="com.sample.hello" name="Hello Process">
    <!-- nodes -->
    <startEvent id="_1" name="Start" />

    <scriptTask id="_2" name="Hello">
      <script>System.out.println("Hello World");</script>
    </scriptTask>

    <endEvent id="_3" name="End" >
      <terminateEventDefinition/>
    </endEvent>

    <!-- connections -->

    <sequenceFlow id="_1-_2" sourceRef="_1" targetRef="_2" />
    <sequenceFlow id="_2-_3" sourceRef="_2" targetRef="_3" />
  </process>

  <bpmndi:BPMNDiagram>
    <bpmndi:BPMNPlane bpmnElement="com.sample.hello" >

      <bpmndi:BPMNShape bpmnElement="_1" >
        <dc:Bounds x="16" y="16" width="48" height="48" />
      </bpmndi:BPMNShape>

      <bpmndi:BPMNShape bpmnElement="_2" >
        <dc:Bounds x="96" y="16" width="80" height="48" />
      </bpmndi:BPMNShape>

      <bpmndi:BPMNShape bpmnElement="_3" >
        <dc:Bounds x="208" y="16" width="48" height="48" />
      </bpmndi:BPMNShape>

      <bpmndi:BPMNEdge bpmnElement="_1-_2" >
        <di:waypoint x="40" y="40" />
        <di:waypoint x="136" y="40" />
      </bpmndi:BPMNEdge>

      <bpmndi:BPMNEdge bpmnElement="_2-_3" >
        <di:waypoint x="136" y="40" />
        <di:waypoint x="232" y="40" />
      </bpmndi:BPMNEdge>

    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>

</definitions>

Chapter 8. Forms in Business Central

A form is a layout definition for a page, defined as HTML, that is displayed as a dialog window to the user during process and task instantiation. Task forms acquire data from a user for both the process and task instance execution, whereas process forms take input and output from process variables.

The input is then mapped to the task using the data input assignment, which you can use inside of a task. When the task is completed, the data is mapped as a data output assignment to provide the data to the parent process instance.

8.1. Form Modeler

Red Hat Process Automation Manager provides a custom editor for defining forms called Form Modeler. With Form Modeler, you can generate forms for data objects, task forms, and process start forms without writing code. Form Modeler includes a widget library for binding multiple data types and a callback mechanism to send notifications when form values change. Form Modeler uses bean-based validation and supports binding form fields to static or dynamic models.

Form Modeler includes the following features:

  • Form modeling user interface for forms
  • Form auto-generation from the data model or Java objects
  • Data binding for Java objects
  • Formula and expressions
  • Customized forms layouts
  • Forms embedding

Form Modeler comes with predefined field types that you place onto the canvas to create a form.

Figure 8.1. Example mortgage loan application form

5011

8.2. Generating process and task forms in Business Central

You can generate a process form from your business process that is displayed at process instantiation to the user who instantiated the process. You can also generate a task form from your business process that is displayed at user task instantiation, when the execution flow reaches the task, to the actor of the user task.

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project name to open the asset view and then click the business process name.
  3. In the process designer, click the process task that you want to create a form for (if applicable).
  4. In the upper-right toolbar, click the Form Generation icon and select the forms that you want to generate:

    • Generate process form: Generates the form for the entire process. This is the initial form that a user must complete when the process instance is started.
    • Generate all forms: Generates the form for the entire process and for all user tasks.
    • Generate forms for selection: Generates the forms for the selected user task nodes.

    Figure 8.2. Form generation menu

    auto form create

    The forms are created in the root directory of your project.

  5. Go to the root directory of your project in Business Central, click the new form name, and use the Form Modeler to customize the form to meet your requirements.

8.3. Manually creating forms in Business Central

You can create task and process forms manually from your project asset view. This is another way to generate a form without selecting to generate forms from your business process. For example, the Form Modeler now supports creating forms from external data objects.

Procedure

  1. In Business Central, go to MenuDesignProjects and click the project name.
  2. Click Add AssetForm.
  3. Provide the following information in the Create new Form window:

    • Form name (must be unique)
    • Package name
    • Model type: Select either Business Process or Data Object.

      • For the Business Process model type, select your business process from the Select Process drop-down menu, and then select the form that you want to create from the Select Form drop-down menu.
      • For the Data Object model type, select one of your project data objects from the Select Data Object from Project drop-down menu.
  4. Click Ok to open the Form Modeler.
  5. In the Components view on the left side of the Form Modeler, expand the Model Fields and Form Controls menus and create a new form by dragging your required fields and form controls to the canvas.
  6. Click Save to save your changes.

8.4. Document attachments in a form or process

Red Hat Process Automation Manager supports document attachments in forms using the Document form field. With the Document form field, you can upload documents that are required as part of a form or process.

To enable document attachments in forms and processes, complete the following procedures:

  1. Set the document marshalling strategy.
  2. Create a document variable in the business process.
  3. Map the task inputs and outputs to the document variable.

8.4.1. Setting the document marshalling strategy

The document marshalling strategy for your project determines where documents are stored for use with forms and processes. The default document marshalling strategy in Red Hat Process Automation Manager is org.jbpm.document.marshalling.DocumentMarshallingStrategy. This strategy uses a DocumentStorageServiceImpl class that stores documents locally in your PROJECT_HOME/docs folder. You can set this document marshalling strategy or a custom document marshalling strategy for your project in Business Central or in the kie-deployment-descriptor.xml file.

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project name and click Settings.

    Figure 8.3. Settings tab

    Selecting the settings tab
  3. Click DeploymentsMarshalling StrategiesAdd Marshalling Strategy.
  4. In the Name field, enter the identifier of a document marshalling strategy, and in the Resolver drop-down menu, select the corresponding resolver type:

    • For single documents: Enter org.jbpm.document.marshalling.DocumentMarshallingStrategy as the document marshalling strategy and set the resolver type to Reflection.
    • For multiple documents: Enter new org.jbpm.document.marshalling.DocumentCollectionImplMarshallingStrategy(new org.jbpm.document.marshalling.DocumentMarshallingStrategy()) as the document marshalling strategy and set the resolver type to MVEL.
    • For custom document support: Enter the identifier of the custom document marshalling strategy and select the relevant resolver type.
  5. Click Test to validate your deployment descriptor file.
  6. Click Deploy to build and deploy the updated project.

    Alternatively, if you are not using Business Central, you can navigate to PROJECT_HOME/src/main/resources/META_INF/kie-deployment-descriptor.xml (if applicable) and edit the deployment descriptor file with the required <marshalling-strategies> elements.

    Example deployment descriptor file with document marshalling strategy for multiple documents

    <deployment-descriptor
        xsi:schemaLocation="http://www.jboss.org/jbpm deployment-descriptor.xsd"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
      <persistence-unit>org.jbpm.domain</persistence-unit>
      <audit-persistence-unit>org.jbpm.domain</audit-persistence-unit>
      <audit-mode>JPA</audit-mode>
      <persistence-mode>JPA</persistence-mode>
      <runtime-strategy>SINGLETON</runtime-strategy>
      <marshalling-strategies>
        <marshalling-strategy>
          <resolver>mvel</resolver>
          <identifier>new org.jbpm.document.marshalling.DocumentCollectionImplMarshallingStrategy(new org.jbpm.document.marshalling.DocumentMarshallingStrategy());</identifier>
        </marshalling-strategy>
      </marshalling-strategies>

8.4.1.1. Using a custom document marshalling strategy for a content management system (CMS)

The document marshalling strategy for your project determines where documents are stored for use with forms and processes. The default document marshalling strategy in Red Hat Process Automation Manager is org.jbpm.document.marshalling.DocumentMarshallingStrategy. This strategy uses a DocumentStorageServiceImpl class that stores documents locally in your PROJECT_HOME/docs folder. If you want to store form and process documents in a custom location, such as in a centralized content management system (CMS), add a custom document marshalling strategy to your project. You can set this document marshalling strategy in Business Central or in the kie-deployment-descriptor.xml file directly.

Procedure

  1. Create a custom marshalling strategy .java file that includes an implementation of the org.kie.api.marshalling.ObjectMarshallingStrategy interface. This interface enables you to implement the variable persistence required for your custom document marshalling strategy.

    The following methods in this interface help you create your strategy:

    • boolean accept(Object object): Determines if the specified object can be marshalled by the strategy
    • byte[] marshal(Context context, ObjectOutputStream os, Object object): Marshals the specified object and returns the marshalled object as byte[]
    • Object unmarshal(Context context, ObjectInputStream is, byte[] object, ClassLoader classloader): Reads the object received as byte[] and returns the unmarshalled object
    • void write(ObjectOutputStream os, Object object): Same as the marshal method, provided for backward compatibility
    • Object read(ObjectInputStream os): Same as the unmarshal method, provided for backward compatibility

    The following code sample is an example ObjectMarshallingStrategy implementation for storing and retrieving data from a Content Management Interoperability Services (CMIS) system:

    Example implementation for storing and retrieving data from a CMIS system

    package org.jbpm.integration.cmis.impl;
    
    import java.io.ByteArrayInputStream;
    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.util.HashMap;
    
    import org.apache.chemistry.opencmis.client.api.Folder;
    import org.apache.chemistry.opencmis.client.api.Session;
    import org.apache.chemistry.opencmis.commons.data.ContentStream;
    import org.apache.commons.io.IOUtils;
    import org.drools.core.common.DroolsObjectInputStream;
    import org.jbpm.document.Document;
    import org.jbpm.integration.cmis.UpdateMode;
    
    import org.kie.api.marshalling.ObjectMarshallingStrategy;
    
    public class OpenCMISPlaceholderResolverStrategy extends OpenCMISSupport implements ObjectMarshallingStrategy {
    
    	private String user;
    	private String password;
    	private String url;
    	private String repository;
    	private String contentUrl;
    	private UpdateMode mode = UpdateMode.OVERRIDE;
    
    	public OpenCMISPlaceholderResolverStrategy(String user, String password, String url, String repository) {
    		this.user = user;
    		this.password = password;
    		this.url = url;
    		this.repository = repository;
    	}
    
    	public OpenCMISPlaceholderResolverStrategy(String user, String password, String url, String repository, UpdateMode mode) {
    		this.user = user;
    		this.password = password;
    		this.url = url;
    		this.repository = repository;
    		this.mode = mode;
    	}
    
    	   public OpenCMISPlaceholderResolverStrategy(String user, String password, String url, String repository, String contentUrl) {
    	        this.user = user;
    	        this.password = password;
    	        this.url = url;
    	        this.repository = repository;
    	        this.contentUrl = contentUrl;
    	    }
    
    	    public OpenCMISPlaceholderResolverStrategy(String user, String password, String url, String repository, String contentUrl, UpdateMode mode) {
    	        this.user = user;
    	        this.password = password;
    	        this.url = url;
    	        this.repository = repository;
    	        this.contentUrl = contentUrl;
    	        this.mode = mode;
    	    }
    
    	public boolean accept(Object object) {
    		if (object instanceof Document) {
    			return true;
    		}
    		return false;
    	}
    
    	public byte[] marshal(Context context, ObjectOutputStream os, Object object) throws IOException {
    		Document document = (Document) object;
    		Session session = getRepositorySession(user, password, url, repository);
    		try {
    			if (document.getContent() != null) {
    				String type = getType(document);
    				if (document.getIdentifier() == null || document.getIdentifier().isEmpty()) {
    					String location = getLocation(document);
    
    					Folder parent = findFolderForPath(session, location);
    					if (parent == null) {
    						parent = createFolder(session, null, location);
    					}
    					org.apache.chemistry.opencmis.client.api.Document doc = createDocument(session, parent, document.getName(), type, document.getContent());
    					document.setIdentifier(doc.getId());
    					document.addAttribute("updated", "true");
    				} else {
    					if (document.getContent() != null && "true".equals(document.getAttribute("updated"))) {
    						org.apache.chemistry.opencmis.client.api.Document doc = updateDocument(session, document.getIdentifier(), type, document.getContent(), mode);
    
    						document.setIdentifier(doc.getId());
    						document.addAttribute("updated", "false");
    					}
    				}
    			}
    			ByteArrayOutputStream buff = new ByteArrayOutputStream();
    	        ObjectOutputStream oos = new ObjectOutputStream( buff );
    	        oos.writeUTF(document.getIdentifier());
    	        oos.writeUTF(object.getClass().getCanonicalName());
    	        oos.close();
    	        return buff.toByteArray();
    		} finally {
    			session.clear();
    		}
    	}
    
    	public Object unmarshal(Context context, ObjectInputStream ois, byte[] object, ClassLoader classloader) throws IOException, ClassNotFoundException {
    		DroolsObjectInputStream is = new DroolsObjectInputStream( new ByteArrayInputStream( object ), classloader );
    		String objectId = is.readUTF();
    		String canonicalName = is.readUTF();
    		Session session = getRepositorySession(user, password, url, repository);
    		try {
    			org.apache.chemistry.opencmis.client.api.Document doc = (org.apache.chemistry.opencmis.client.api.Document) findObjectForId(session, objectId);
    			Document document = (Document) Class.forName(canonicalName).newInstance();
    			document.setAttributes(new HashMap<String, String>());
    
    			document.setIdentifier(objectId);
    			document.setName(doc.getName());
    			document.setLastModified(doc.getLastModificationDate().getTime());
    			document.setSize(doc.getContentStreamLength());
    			document.addAttribute("location", getFolderName(doc.getParents()) + getPathAsString(doc.getPaths()));
    			if (doc.getContentStream() != null && contentUrl == null) {
    				ContentStream stream = doc.getContentStream();
    				document.setContent(IOUtils.toByteArray(stream.getStream()));
    				document.addAttribute("updated", "false");
    				document.addAttribute("type", stream.getMimeType());
    			} else {
    			    document.setLink(contentUrl + document.getIdentifier());
    			}
    			return document;
    		} catch(Exception e) {
    			throw new RuntimeException("Cannot read document from CMIS", e);
    		} finally {
    			is.close();
    			session.clear();
    		}
    	}
    
    	public Context createContext() {
    		return null;
    	}
    
    	// For backward compatibility with previous serialization mechanism
    	public void write(ObjectOutputStream os, Object object) throws IOException {
    		Document document = (Document) object;
    		Session session = getRepositorySession(user, password, url, repository);
    		try {
    			if (document.getContent() != null) {
    				String type = document.getAttribute("type");
    				if (document.getIdentifier() == null) {
    					String location = document.getAttribute("location");
    
    					Folder parent = findFolderForPath(session, location);
    					if (parent == null) {
    						parent = createFolder(session, null, location);
    					}
    					org.apache.chemistry.opencmis.client.api.Document doc = createDocument(session, parent, document.getName(), type, document.getContent());
    					document.setIdentifier(doc.getId());
    					document.addAttribute("updated", "false");
    				} else {
    					if (document.getContent() != null && "true".equals(document.getAttribute("updated"))) {
    						org.apache.chemistry.opencmis.client.api.Document doc = updateDocument(session, document.getIdentifier(), type, document.getContent(), mode);
    
    						document.setIdentifier(doc.getId());
    						document.addAttribute("updated", "false");
    					}
    				}
    			}
    			ByteArrayOutputStream buff = new ByteArrayOutputStream();
    	        ObjectOutputStream oos = new ObjectOutputStream( buff );
    	        oos.writeUTF(document.getIdentifier());
    	        oos.writeUTF(object.getClass().getCanonicalName());
    	        oos.close();
    		} finally {
    			session.clear();
    		}
    	}
    
    	public Object read(ObjectInputStream os) throws IOException, ClassNotFoundException {
    		String objectId = os.readUTF();
    		String canonicalName = os.readUTF();
    		Session session = getRepositorySession(user, password, url, repository);
    		try {
    			org.apache.chemistry.opencmis.client.api.Document doc = (org.apache.chemistry.opencmis.client.api.Document) findObjectForId(session, objectId);
    			Document document = (Document) Class.forName(canonicalName).newInstance();
    
    			document.setIdentifier(objectId);
    			document.setName(doc.getName());
    			document.addAttribute("location", getFolderName(doc.getParents()) + getPathAsString(doc.getPaths()));
    			if (doc.getContentStream() != null) {
    				ContentStream stream = doc.getContentStream();
    				document.setContent(IOUtils.toByteArray(stream.getStream()));
    				document.addAttribute("updated", "false");
    				document.addAttribute("type", stream.getMimeType());
    			}
    			return document;
    		} catch(Exception e) {
    			throw new RuntimeException("Cannot read document from CMIS", e);
    		} finally {
    			session.clear();
    		}
    	}
    
    }

  2. In Business Central, go to MenuDesignProjects.
  3. Click the project name and click Settings.

    Figure 8.4. Settings tab

    Selecting the settings tab
  4. Click DeploymentsMarshalling StrategiesAdd Marshalling Strategy.
  5. In the Name field, enter the identifier of the custom document marshalling strategy, such as org.jbpm.integration.cmis.impl.OpenCMISPlaceholderResolverStrategy in this example.
  6. Select the relevant option from the Resolver drop-down menu, such as Reflection in this example.
  7. Click Test to validate your deployment descriptor file.
  8. Click Deploy to build and deploy the updated project.

    Alternatively, if you are not using Business Central, you can navigate to PROJECT_HOME/src/main/resources/META_INF/kie-deployment-descriptor.xml (if applicable) and edit the deployment descriptor file with the required <marshalling-strategies> elements.

    Example deployment descriptor file with custom document marshalling strategy

    <deployment-descriptor
        xsi:schemaLocation="http://www.jboss.org/jbpm deployment-descriptor.xsd"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
      <persistence-unit>org.jbpm.domain</persistence-unit>
      <audit-persistence-unit>org.jbpm.domain</audit-persistence-unit>
      <audit-mode>JPA</audit-mode>
      <persistence-mode>JPA</persistence-mode>
      <runtime-strategy>SINGLETON</runtime-strategy>
      <marshalling-strategies>
        <marshalling-strategy>
          <resolver>reflection</resolver>
          <identifier>
            org.jbpm.integration.cmis.impl.OpenCMISPlaceholderResolverStrategy
          </identifier>
        </marshalling-strategy>
      </marshalling-strategies>

  9. To enable documents stored in a custom location to be attached to forms and processes, create a document variable in the relevant processes and map task inputs and outputs to that document variable in Business Central.

8.4.2. Creating a document variable in a business process

After you set a document marshalling strategy, create a document variable in the related process to upload documents to a human task and for the document or documents to be visible in the Process Instances view in Business Central.

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project name to open the asset view and click the business process name.
  3. Click the canvas and click diagram properties on the right side of the window to open the Diagram properties panel.
  4. Expand Process Data and click 6176 and enter the following values:

    • Name: document
    • Custom Type: org.jbpm.document.Document for a single document or org.jbpm.document.DocumentCollection for multiple documents

8.4.3. Mapping task inputs and outputs to the document variable

If you want to view or modify the attachments inside of task forms, create assignments inside of the task inputs and outputs.

Procedure

  1. In Business Central, go to MenuDesignProjects.
  2. Click the project name to open the asset view and click the business process name.
  3. Click a user task and click diagram properties on the right side of the window to open the Diagram properties panel.
  4. Expand Implementation/Execution and next to Assignments, click btn assign to open the Data I/O window.
  5. Next to Data Inputs and Assignments, click Add and enter the following values:

    • Name: taskdoc_in
    • Data Type: org.jbpm.document.Document for a single document or org.jbpm.document.DocumentCollection for multiple documents
    • Source: document
  6. Next to Data Outputs and Assignments, click Add and enter the following values:

    • Name: taskdoc_out
    • Data Type: org.jbpm.document.Document for a single document or org.jbpm.document.DocumentCollection for multiple documents
    • Target: document

    The Source and Target fields contain the name of the process variable you created earlier.

  7. Click Save.

Chapter 9. Invoking a Decision Model and Notation (DMN) service in a business process

You can use Decision Model and Notation (DMN) to model a decision service graphically in a decision requirements diagram (DRD) in Business Central and then invoke that DMN service as part of a business process in Business Central. Business processes interact with DMN services by identifying the DMN service and mapping business data between DMN inputs and the business process properties.

As an illustration, this procedure uses an example TrainStation project that defines train routing logic. This example project contains the following data object and DMN components designed in Business Central for the routing decision logic:

Example Train object

public class Train {

     private String departureStation;

     private String destinationStation;

     private BigDecimal railNumber;

     // Getters and setters
}

Figure 9.1. Example Compute Rail DMN model

dmn execution graph

Figure 9.2. Example Rail DMN decision table

dmn execution expression

Figure 9.3. Example tTrain DMN data type

dmn execution data type

For more information about creating DMN models in Business Central, see Designing a decision service using DMN models.

Prerequisites

  • All required data objects and DMN model components are defined in the project.

Procedure

  1. In Business Central, go to MenuDesignProjects and click the project name.
  2. Select or create the business process asset in which you want to invoke the DMN service.
  3. In the process designer, use the left toolbar to drag and drop BPMN components as usual to define your overall business process logic, connections, events, tasks, or other elements.
  4. To incorporate a DMN service in the business process, add a Business Rule task from the left toolbar or from the start-node options and insert the task in the relevant location in the process flow.

    For this example, the following Accept Train business process incorporates the DMN service in the Route To Rail node:

    Figure 9.4. Example Accept Train business process with a DMN service

    dmn execution business process
  5. Select the business rule task node that you want to use for the DMN service, click Diagram properties in the upper-right corner of the process designer, and under Implementation/Execution, define the following fields:

    • Rule Language: Select DMN.
    • Namespace: Enter the unique namespace from the DMN model file. Example: https://www.drools.org/kie-dmn
    • Decision Name: Enter the name of the DMN decision node that you want to invoke in the selected process node. Example: Rail
    • DMN Model Name: Enter the DMN model name. Example: Compute Rail
  6. Under Data AssignmentsAssignments, click the Edit icon and add the DMN input and output data to define the mapping between the DMN service and the process data.

    For the Route To Rail DMN service node in this example, you add an input assignment for Train that corresponds to the input node in the DMN model, and add an output assignment for Rail that corresponds to the decision node in the DMN model. The Data Type must match the type that you set for that node in the DMN model, and the Source and Target definition is the relevant variable or field for the specified object.

    Figure 9.5. Example input and output mapping for the Route To Rail DMN service node

    dmn execution io mapping
  7. Click Save to save the data input and output data.
  8. Define the remainder of your business process according to how you want the completed DMN service to be handled.

    For this example, the Diagram propertiesImplementation/ExecutionOn Exit Action value is set to the following code to store the rail number after the Route To Rail DMN service is complete:

    Example code for On Exit Action

    train.setRailNumber(rail);

    If the rail number is not computed, the process reaches a No Appropriate Rail end error node that is defined with the following condition expression:

    Figure 9.6. Example condition for No Appropriate Rail end error node

    dmn execution negative condition

    If the rail number is computed, the process reaches an Accept Train script task that is defined with the following condition expression:

    Figure 9.7. Example condition for Accept Train script task node

    dmn execution positive condition

    The Accept Train script task also uses the following script in Diagram propertiesImplementation/ExecutionScript to print a message about the train route and current rail:

    com.myspace.trainstation.Train t =
        (com.myspace.trainstation.Train) kcontext.getVariable("train");
    System.out.println("Train from: " + t.getDepartureStation() +
                       ", to: " + t.getDestinationStation() +
                       ",  is on rail: " + t.getRailNumber());
  9. After you define your business process with the incorporated DMN service, save your process in the process designer, deploy the project, and run the corresponding process definition to invoke the DMN service.

    For this example, when you deploy the TrainStation project and run the corresponding process definition, you open the process instance form for the Accept Train process definition and set the departure station and destination station fields to test the execution:

    Figure 9.8. Example process instance form for the Accept Train process definition

    dmn execution process instance form

    After the process is executed, a message appears in the server log with the train route that you specified:

    Example server log output for the Accept Train process

    Train from: Zagreb, to: Belgrade,  is on rail: 1

Chapter 10. Additional resources

Appendix A. Versioning information

Documentation last updated on Thursday, October 31, 2019.

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