7
Using Oracle Workflow

This chapter discusses using Oracle Workflow to apply business logic to an integration. Topics include:

• Oracle Workflow Overview

• OracleAS InterConnect Integration with Oracle Workflow

• Using Oracle Workflow to Apply Business Logic

• Design Business Process

Oracle Workflow Overview

Oracle Workflow is integrated with OracleAS InterConnect and is used for business process collaborations across two or more applications. A business process collaboration is defined as the conversation between two or more applications in the context of a business process.

OracleAS InterConnect leverages the robust design time and runtime Oracle Workflow business process definition and execution support to make business processes explicit and manageable.

Note: Knowledge of Oracle Workflow, its tools, and its Business Event System is required to utilize OracleAS InterConnect and Oracle Workflow for business process collaboration. For more information on Oracle Workflow, see Oracle Workflow Administrator's Guide.

Oracle Workflow Solves Common Business Problems

The following are some of the common business problems that can be solved using Oracle Workflow.

Error Management

If there is a problem in a conversation between two or more applications, the errors arising from this problem can be centrally managed and appropriate remedial actions can be defined. For example, it may be required to keep the data of an order entry system synchronize with a backend ERP system. Consider that a new purchase order is created in the order entry system but the ERP system is down at the time the purchase order is created. At a later time, the ERP system comes back up and an attempt is made to create a corresponding new purchase order through messaging using OracleAS InterConnect. This attempt fails. To deal with this scenario, the integrator can utilize Oracle Workflow to send a compensating message to the order entry system to undo the creation of the purchase order and notify the user who created the order.

In the example above, OracleAS InterConnect and Oracle Workflow can be used to model the following for every purchase order that is over $50,000:

• Send a notification to a named approver and wait for approval.

• If approved, send the message to the ERP system. Otherwise send a message to the order entry system to rollback the order creation.

Message Junctions

Fan-in and fan-out of messages can be effectively modeled using OracleAS InterConnect and Oracle Workflow. Fan-in messages involve combining two or more messages into one. Fan-out messages involve splitting one message into two or more.

For an example of fan-in messaging, consider the following. A global organization has a centralized Human Resources Enterprise Resource Planning (ERP) application in the United States. Each country has one or more local systems that capture local employee information. If a new employee joins the Japanese branch of this organization, data is entered into a local human resources application and a local Benefits application. Each entry launches a message for adding this information to the centralized system. However, the centralized system needs data from both systems combined and will only commit the data if it was entered successfully in both of the local systems connecting to OracleAS InterConnect. Using Oracle Workflow, this process can be modeled so that OracleAS InterConnect routes messages from both local systems to Oracle Workflow, Oracle Workflow waits until it receives both messages, combines the data, and launches a single message to be delivered by OracleAS InterConnect to the centralized human resources system.

Stateful Routing

OracleAS InterConnect provides extensive support for stateless routing through event-based and content-based routing features. Using Oracle Workflow, stateful routing can be accomplished. In other words, the decision to route can be based on more than the event or the content of the message.

Composite Services

Combining all of the examples, an internal (organization focused) or external (customer/partner focused) service can be built through a well-defined set of business processes involving communication between two or more applications. For example, a brick-and-mortar retail company wants to provide an on-line procurement service to their customers. Behind the user interface are several business processes controlling communication across several internal applications to deliver a robust, performant service to the customer.

Note: The ability to define explicit business process collaborations is a feature, not a requirement for completing integrations. It is not necessary to utilize Oracle Workflow for integration if the business process definition is simple enough to be implicitly captured in the messaging through the core functionality in iStudio.

OracleAS InterConnect Integration with Oracle Workflow

The following describes how OracleAS InterConnect and Oracle Workflow are integrated.

Design Time Tools

During design time, business process and event definitions in iStudio can be deployed to Oracle Workflow. Consequently, Oracle Workflow tools can be launched from within iStudio to graphically create process diagrams in the context of enterprise integration through OracleAS InterConnect.

Using iStudio, the following tools can be launched:

• Oracle Workflow Builder--Use this tool to complete business process definitions defined and deployed through iStudio. This is accomplished by using Oracle Workflow Builder to create process diagrams.

  Figure 7-1 Oracle Workflow Builder

  

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• Oracle Workflow Home Page--Use this tool for centralized access to the web-based features of Oracle Workflow. The Business Event System management and administration is the most important feature exposed through this home page.

  For more information on the Business Event System, see Oracle Workflow Administrator's Guide.

  Figure 7-2 Oracle Workflow Home Page

  

  Text description of the illustration sc2.gif

Runtime

At runtime, OracleAS InterConnect integrates with the Business Event System of Oracle Workflow. The Business Event System is an application service that uses the Advanced Queueing infrastructure to communicate business events between systems. OracleAS InterConnect registers itself as an external system in Business Event System so the following conditions exist:

• Messages can flow from applications through OracleAS InterConnect, in the common view format, to the Business Event System. This will either trigger or continue Oracle Workflow business processes as defined using iStudio (Business Processes) and described using Oracle Workflow Builder (Process Diagrams).

• Messages can flow from the Business Event System to OracleAS InterConnect in the common view format to applications to either continue or end Oracle Workflow business processes.

At runtime, Oracle Workflow is integrated with OracleAS InterConnect at the hub. Messages are passed back and forth between OracleAS InterConnect and the Business Event System of Oracle Workflow via Advanced Queues. The OracleAS InterConnect Oracle Workflow Communication Infrastructure facilitates this communication.

At design time, to keep the integration methodology consistent, iStudio reuses the messaging paradigms of publish/subscribe and request/reply to specify communication between OracleAS InterConnect and Oracle Workflow. Therefore, for messages inbound into Oracle Workflow, the iStudio user can specify, in the context of a business process, which events Oracle Workflow is subscribing to and which procedures Oracle Workflow is implementing. For outbound messages, events that Oracle Workflow can publish and procedures it can invoke can be specified.

See Also: "Using Oracle Workflow to Apply Business Logic"

Using Oracle Workflow to Apply Business Logic

This section describes using OracleAS InterConnect with Oracle Workflow. There are three broad steps:

1. Install Oracle Workflow Components

2. Design Business Process

3. Deploy Business Processes for Runtime

Install Oracle Workflow Components

You need to install the necessary Oracle Workflow components and perform required configuration tasks following the procedures described in Oracle Application Server InterConnect Installation Guide.

Design Business Process

To deploy the business process:

• Design process bundles using iStudio.

• Deploy process bundles from iStudio to a .wft file.

• Complete process diagrams in Oracle Workflow Builder by launching Oracle Workflow Builder from iStudio and using the deployed .wft file.

Deploy Business Processes for Runtime

To deploy business processes for runtime:

• Deploy events to the Business Event System from iStudio.

• Deploy a process diagram from a file to the database using Oracle Workflow Builder.

Design Business Process

The following concepts discuss how iStudio and Oracle Workflow work together in OracleAS InterConnect. In addition, these topics discuss how to use iStudio and Oracle Workflow step by step during design time for business process collaborations across applications.

Process Bundle

A process bundle is a set of logically related business processes. This maps one-to-one with an Oracle Workflow item.

See Also: "Business Process"

Business Process

A business process is a set of OracleAS InterConnect common view events or procedures that must be routed to and from Oracle Workflow in one Oracle Workflow business process. These events and procedures manifest themselves as Oracle Workflow business events and can be used to define a process diagram in Oracle Workflow Builder. This maps one-to-one with an Oracle Workflow business process.

Activity

Activities in iStudio allow the user to define the common view events and procedures that must be a part of an Oracle Workflow business process. The following are types of activities in iStudio:

• Publish Event--Oracle Workflow publishes an OracleAS InterConnect common view event. At deployment time, a business event corresponding to the common view event is created in the Business Event System.

• Subscribe Event--Oracle Workflow subscribes to an OracleAS InterConnect common view event. At deployment time, a business event corresponding to the common view event is created in the Business Event System.

• Invoke Procedure--Oracle Workflow invokes an OracleAS InterConnect common view procedure. At deployment time, two business events corresponding to the common view procedure are created in the Business Event System, one event for sending the request and the other for receiving the reply.

• Implement Procedure--Oracle Workflow implements an OracleAS InterConnect common view procedure. At deployment time, two business events corresponding to the common view procedure are created in the Business Event System, one event for receiving the request and the other for sending the reply.

The following table describes how iStudio and Oracle Workflow concepts are mapped.

iStudio Concept	Oracle Workflow Concept	Mapping
Process Bundle	Item	One-to-one.
Business Process	Business Process	One-to-one.
Common View Event	Business Event	One-to-one.Foot 1
Common View Procedure	Business Event	Two business events per procedure.
Publish Activity	Send Event Activity	One-to-one.
Subscribe Activity	Receive Event Activity	One-to-one.
Invoke Activity	Send Event Activity (for the request) Receive Event Activity (for the reply)
Implement Activity	Receive Event Activity (for the request) Send Event Activity (for the reply)

1 Only for all events that are part of a business process in iStudio. Events that are part of the common view but not part of a business process are not instantiated as Oracle Workflow business events. All common view events need not be part of business processes. In other words, depending on the integration, some common view events could be exchanged directly between applications without involving Oracle Workflow using the core functionality of OracleAS InterConnect. Other events may need to be part of an explicit business process. It is the latter set of events that become business events in Oracle Workflow. The same is true for common view procedures.

Creating a Process Bundle

To create a process bundle using iStudio:

1. From the project tree, click Workflow and expand the subtree.

2. Right-click on Process Bundles and select New. The Create Process Bundle dialog displays.

3. Enter the name of the process bundle in the Process Bundle Name field and click OK.

Creating a Business Process

To create a business process:

1. From the project tree, expand the process bundle for which the business process is to be created.

2. Right-click on Business Processes and select New. The Create Business Process dialog displays.

3. Enter a name for the business process in the Business Process Name field and click OK.

Populating a Business Process with Activities

To populate a business process with activities:

1. From the project tree, select the business process to populate.

2. Right-click the business process and in the context menu, select the activity to be part of the business process. Choose from the following activities:
   • New Publish Activity--Oracle Workflow sends a message to OracleAS InterConnect in the context of the business process.

   • New Subscribe Activity--Oracle Workflow receives a message from OracleAS InterConnect.^{Foot 1}

   • New Invoke Activity--Oracle Workflow sends a request message to OracleAS InterConnect and receives a reply.

   • New Implement Activity--Oracle Workflow receives a request from OracleAS InterConnect and sends a reply.

   The Subscribe Activity Wizard displays.

3. Select an event for the activity.

   

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4. Click Finish.

   Repeat these steps for adding other activities to the process.

   Note: When you create multiple activities under a business process, the list of activities is unordered. For example. the order in which the activities are added is not important. The order can be later decided in Oracle Workflow Builder through a process diagram.

Deploying to Oracle Workflow

After populating business processes with activities, this information must be deployed to Oracle Workflow to graphically model a business process. To deploy this information to Oracle Workflow:

1. On the Deploy tab in iStudio, right click on Workflow and select Deploy.

   The Deploy dialog displays:

   

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2. There are two sets of information that need to be deployed. They can be done independently or together:
   • Oracle Workflow Business Events--Business Events need to be created in the Business Event System of Oracle Workflow. This is a requirement for runtime only. Using Oracle Workflow Builder, users can decide not to deploy these until all design time work, including modeling the business process, is complete.

     Note: iStudio checks if an event is already deployed before deploying it. Therefore, users can safely decide to re-deploy all events at anytime. However, deploying events after all the design time work has been completed saves you the effort of redeploying events repeatedly.

     To check if events have been deployed, launch the Oracle Workflow Home page.

     See Also: "Launching the Oracle Workflow Home Page" for more information on the Oracle Workflow Home page.

   • Oracle Workflow Process Definitions through .wft file generation--Information about business processes captured in iStudio provides a foundation for building process diagrams in Oracle Workflow Builder. Deploying process definitions is required for design time.

     Note: When deploying process definitions, iStudio prompts for a filename. If an existing file is specified, iStudio will overwrite the file. Therefore, if there are existing process definitions in a file modified using Oracle Workflow Builder, do not select that filename as the target, otherwise all modifications made will be lost.

   By default, both choices are selected. The dialog also allows the following to be automatically launched:

   • Oracle Workflow Builder--Defines business process diagrams.

   • Oracle Workflow Home Page--Verifies Business Event deployment.

   By default, these choices are unselected. Choose to launch these tools with deployment or complete this task at a later time on the Design tab.

   See Also: "Launching Oracle Workflow Tools"

3. Select the appropriate choices and click OK.

   If deploying event definitions to the Oracle Workflow Business Event System is selected, the following dialog displays:

   

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4. Enter the required information based on the selections made during Oracle Workflow installation and click OK.

   If Deploying Process Definitions to a .wft file was selected, a file dialog displays:

   

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5. Enter the name and location of the file to create and click OK.

   Note: When deploying process definitions, iStudio prompts for a filename. If an existing file is specified, iStudio will overwrite the file. Therefore, if there are existing process definitions in a file modified using Oracle Workflow Builder, do not select that filename as the target, otherwise all modifications made will be lost.

Launching Oracle Workflow Tools

The following topics discuss how to launch Oracle Workflow tools in iStudio.

Launching the Oracle Workflow Home Page

To launch the Oracle Workflow Home page:

1. On the Design tab in iStudio, right click on Workflow and select Launch WF Home Page. The Oracle Workflow Home Page dialog displays:

   

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2. Make sure the URL is correct and click on OK.

   The Username and Password Required dialog displays:

   

   Text description of the illustration sc22.gif

3. Enter the login information for the Oracle Workflow Home Page and click OK.

   The Oracle Workflow Home page is launched using the default browser.

Launching Oracle Workflow Builder

To launch Oracle Workflow Builder:

1. On the Design tab in iStudio, right click on the process bundle to view in Oracle Workflow Builder and select Launch Workflow Builder. The Deploy dialog displays:

   

   Text description of the illustration sc19.gif

2. In the Deploy dialog, select an existing .wft file name to load into Oracle Workflow Builder.

   Note: The assumption is that a process definition has already been deployed to a file.

   Oracle Workflow Builder is launched depending on which process definition file is selected.

   Note: To launch Oracle Workflow Builder outside of a specific OracleAS InterConnect process bundle, right-click on Workflow and select Launch Workflow Builder.

Modifying Existing Oracle Workflow Processes

When modifying existing Oracle Workflow processes, do not add, modify, or remove OracleAS InterConnect event activities directly in Oracle Workflow Builder. Always make all event-related process changes in iStudio, redeploy to the file, and import in Oracle Workflow Builder.

For example, the following steps were completed to create an integration-related Oracle Workflow business process:

1. Create a process bundle in iStudio and create business processes with some activities.

2. Deploy to the my_process_bundle.wft file.

3. Import the file into Oracle Workflow Builder.

4. Make non-event related modifications to the process in Oracle Workflow Builder, such as adding other activities like notifications and decision functions to complete the business process.

5. Save the modified process to my_process_bundle.wft.

At this point, you need to make some event-related modifications to the business process. For example, add two new events to the business process with the following steps:

6. Using iStudio, make the additions to the particular business process.

7. Deploy to a different file such as changes_to_my_process_bundle.wft. Do not deploy to my_process_bundle.wft because any non-event-related modifications made through Oracle Workflow Builder will be lost.

8. Launch Oracle Workflow Builder and import both my_process_bundle.wft and changes_to_my_process_bundle.wft.

9. Drag the required modifications from the process representing changes_to_my_process_bundle.wft to the process representing my_process_bundle.wft.

10. Save the modified process to my_process_bundle.wft.

    The my_process_bundle.wft file now contains the updated process definition with both the event and the non-event modifications.

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¹ This example is used for explaining the steps. The steps are similar regardless of the selection.