What is bpel process

BPEL example workflow Source. Because of these 10 aims, BPEL particularly the 2. When your organization can access many internal and external services, BPEL can take all the data and make it readily available to you from a centralized location. Using external web services actually adds to the overall automation process—web services handle both abstract business and executable business processes, allowing your staff to spend more human hours on what you need them to. Similarly, new aspects of the infrastructure can be immediately integrated with BPEL and web services, allowing large scale improvements to business process.

Whenever new applications or infrastructure is added, they can be immediately integrated with new process descriptions. Large scale changes cause problems for many organizations, but the BPEL process management is there to make the process as painless as possible.

Orchestration in action Source. When Salesforce needs to interact with the head CRM application, BPEL can be used to automatically communicate between the BPEL powered execution environment or the engine and the platform and allow for proper application integration. BPEL is perfect for data collection and manipulation. Businesses live and die on their ability to repeat mission critical tasks. When these tasks can become more agile and performed without expensive integrations, a business can look forward to developing their process.

Integrating BPEL is perfect for businesses that have a wide range of process descriptions that can make the leap to the world of automation. For the clients, the BPEL process will expose its functionality in the same way as any other Web service. From the client perspective, it will look exactly like any other Web service. This is important and useful, as it allows us to compose services into simple processes, simple processes into more complex processes, and so on. A BPEL process consists of steps.

Each step is called an activity. BPEL supports primitive and structure activities. Primitive activities represent basic constructs and are used for common tasks, such as those listed below:. We can then combine these activities into more complex algorithms that specify the steps of a business process.

To combine primitive activities, BPEL supports several structure activities. The most important are:. BPEL also provides fault and compensation handlers, event handlers, and correlation sets. It provides means to express complex parallel flows. It also makes it relatively easy to call asynchronous operations and wait for callbacks. Typically, BPEL servers provide control over process instances that are executing and those that have finished. They support long-running processes and can dehydrate process state to save resources.

Some servers provide control over process activities and allow their monitoring. Finally, using a BPEL server, all our processes are deployed centrally, which simplifies maintenance.

All this makes the BPEL server the preferred environment for running and managing processes. Choosing the right BPEL server can be quite difficult, however, as there are several choices.

Let us now look at an example BPEL process for business travels that we have described above. We will develop an asynchronous process that will use a synchronous call to check the employee travel status and two asynchronous calls to acquire the plane ticket prices. The figure below shows the overall structure of our process. On the left, we see the client that invokes the process.

The process first calls the employee travel status Web service. Then it invokes both airlines' Web services concurrently and asynchronously. This means that the process will have to implement the callback operation and a port type , through which the airlines will return the flight ticket confirmation.

Finally, the process returns the best airline ticket offer to the client. In this example, to maintain simplicity, we will not implement any fault handling, which is crucial in real-world scenarios.

Let us now write the BPEL code. These chapters are useful for any developer interested in understanding the underlying functionality of BPEL. Specific topics discussed include the following:. Appendices in this part provide reference details about troubleshooting, supported activities, user accounts, XPath expression functions, Oracle Workflow support, and other features.

Table describes the contents of the samples directory. New samples are periodically added. Contains a set of common business scenarios and describes how they are implemented with BPEL. Table provides descriptions of the available demonstrations. Apache Axis.

BEA WebLogic. Table provides descriptions of the available activities and concepts. Table provides descriptions of the available tutorials.

Table describes the BPEL process demonstrations available for use in the demos directory. See the documentation available in these directories for instructions on running these demonstrations.

You can also click the. Describes how to perform a bank transfer. The sample shows two types of transaction management:. Describes how to create a business process for reviewing a document in parallel. A final reviewer reviews comments from each of the parallel reviewers.

A worklist application views and acts on the tasks. This example highlights the use of the following features:. Describes how to process a help desk service request. The demonstration uses a workflow for accepting or rejecting a service request. This sample illustrates the asynchronous multistep conversation between two BPEL processes. The second process waits for 30 seconds and responds asynchronously. Then the first process waits for 30 seconds and calls the second process again.

The second process responds again after 30 seconds. Describes how to integrate a synchronous credit rating service and two asynchronous loan processor services into an end-to-end loan procurement application with a Java Server Page JSP user interface to initiate the process and view loan offer results.

Describes how to extend the LoanDemo sample to use Java embedding exception management, including manual processing steps and development of a richer custom user interface.

Describes how to extend the LoanDemo sample to use a worklist application to approve or reject a loan application. Describes how to approve or reject an order. The approval or rejection is a two-step process involving an initial approver and the manager of the initial approver. OrderApproval also illustrates the use of workflow for multiple approvals. This sample illustrates how to use the nonBlockingInvoke property in bpel. This property enables you to execute a synchronous BPEL process calling multiple synchronous Web services in flow in real parallel mode.

Use a pick activity to control a process flow based on the outcome of another process including a timeout for the process. This process also illustrates the use of workflow for simple approvals, and the use of a deployment descriptor preference to replace a hard-coded value in the BPEL logic.

Describes how to invoke a service n times using a While loop activity. This sample illustrates the ability of the process priorities.

Oracle BPEL Server uses the priorities for scheduling work such that higher priority processes get executed in advance of lower priority processes when there is contention for engine execution threads. Describes how to use a BPEL process to manage fault handling and run time exceptions. Describes how to integrate the Salesforce. Describes how to use a process that receives a number, creates that number of branches using the flowN activity, and waits for a period of time based on the index variable setting.

This process receives an integer as input. It creates that number of branches using bpelx:flowN. In each branch, a wait activity is executed. The wait time is based on the index variable. Describes how to design user interactions and workflow tasks within a BPEL process. This sample illustrates use of the User Task and e-mail notification service. Describes how to approve or reject a vacation request. The approval or rejection is a one-step process involving the manager of the user filing the vacation request.

This demonstration also describes the use of workflow for simple approvals, and the use of a deployment descriptor preference to replace a static parameter value in the BPEL process. Describes how to create a transformation that maps a purchase order schema to an invoice schema. Table describes the activity and conceptual references available for review and use in the references directory.

The comment lines in each bpel. Shows how to receive an input string, prefix Hello to it using an assign activity, and asynchronously return the result. Shows how to use custom XPath functions within assign activities. Shows how to update dynamic partner links. Shows how to enable an asynchronous BPEL process and use event handlers to receive and process events while waiting for the asynchronous callback.

Shows how a link defines dependencies between executions of activities. In this sample, a link in a flow activity sequences the execution of two service invocations. Shows how to invoke an asynchronous loan service and use a BPEL pick activity to receive an asynchronous response or a timeout message.

If the loan amount is more than , it takes about 30 seconds for the server to process it, causing a timeout to be raised. Shows how to invoke an asynchronous loan service and wait for an asynchronous callback message using the BPEL receive activity. Shows how to receive a string as input, perform an assign, and use the reply activity to synchronously return the modified string. Shows how to use a switch activity to return a different text message based on whether the input value is greater or less than zero.

Shows how to invoke a synchronous stock quoting service. The terminate activity then aborts, causing the final callback invoke activity to be skipped. Shows how to invoke an incremental service n times with a while activity, where n is provided as an input value. Shows how to receive an invalid application, perform several XPath copies, and asynchronously return the application.