Business process integration technology based on BPEL

Introduction

Based on WebService, an SOA (Service Oriented Architecture) architecture is used to establish an enterprise business system solution, analyzing and clarifying the business process of the enterprise and defining the Web service to fit the granularity. When it comes to cross departmental, end-to-end business process dynamic integration, these Web services need to be combined sequentially to achieve business process integration methods and technologies. Therefore, under the SOA architecture, BPEL is used as the business Process Execution language to study the implementation of business process dynamic integration among enterprise departments.

1 BPEL and business process choreography

The study uses IBM's methodology for SOA, industry solutions, and related technology products, so research on BPEL conforms to IBM's core component standards for SOA SCA/SDO (Service Component architecture/service Data Object). SDO is an application programming interface (API) that simplifies and unifies access to heterogeneous data; SCA is a new, language-independent programming model that provides a unified invocation approach that allows customers to encapsulate and invoke different component types through a standard interface. Combining the SDO data model, the programming model of this service component simplifies programmer programming and improves application flexibility. The SCA/SDO standard layering and relationships are shown in Figure 1.

where business processes (BPC) is a component that satisfies the SCA specification, SCA implements the service component layer through the Unified component specification, internally can be javabeans,bpel-processes and so on. Although BPC is only one of the SCA components in the SCA/SDO standard, it is unavoidable to interact with other SCA components (such as the Human Tasks, Business rules, and so on) while building a business process, so it is not possible to study the BPC component in isolation.

The standard BPEL specification is defined in terms of transport, messaging, service discovery, QOS (Quality's service) and orchestration Orchestration (Business process choreography), focusing on business process choreography. In the orchestration and implementation of the business process, the first need to model the business process, the real restoration of the current business scene (called As.is), and then according to business objectives, the implementation of Business process optimization (called to-be), and then according to the actual operation of the results of the next round of optimization. This is a cycle-iterative process that conforms to the SOA lifecycle: Modeling (model) assembly (assemble) one deployment (deploy) one Management (manager), while orchestration orchestration is complete throughout the SOA lifecycle.

When defining the BPC component, the component interfaces and references must conform to the SCA component specification, define Java interface/reference or interface/reference, and the specific implementation of the component is business processes as shown in Figure 2.

According to the BPEL specification, when implementing the BPC component, each step of the process is called an activity, with the following basic activities: Invoking the operation of a Web service (invoke); Waiting for a message to respond to an operation that calls a service interface from outside (receive) Generate input/output response (reply), wait for a period of time, copy data from one place to another (assign), indicate a place error (throw), terminate an entire service instance (terminate), or do nothing (empty). These primitive activities can be combined into more complex algorithms by using the structured activities provided by the BPEL language. The capabilities provided by these structured activities include defining a sequence of sequential sequences (sequence), using the "case.statement" method to produce a branch (switch), defining a loop (while), and executing one of several optional paths (pick) Indicates a set of steps (flow) that should be executed in parallel; In a set of activities that are executed in parallel, a link (1ink) can be used to indicate the constraints of the execution order, and to allow the recursive combination of structured activities to express arbitrary complex algorithms that represent the implementation of the service.

2 Service Assembly

Use IBM Websphere Integration Development6.0.1 (WID) to complete the Services assembly (service Assemble) in the SOA life-style. The above basic activities, structured activities in the WID have been a degree of encapsulation and detail shielding, through the wid provided by the graphical editor to complete the BPEL process orchestration, as shown in Figure 3.