【Apache 之ODE介绍】

Apache ODE (Orchestration Director Engine) software executes business processes written following the WS-BPEL standard. It talks to web services, sending and receiving messages, handling data manipulation and error recovery as described by your process definition. It supports both long and short living process executions to orchestrate all the services that are part of your application.

ODE的开发目标是建立一个可靠的、轻型的、可嵌入的能够管理长时间运行流程的组件，该流程由BPEL流程描述语言定义。开发核心是创建一些小模块，这些小模块具有很小的互相的依赖性，通过很容易的组装这些组件可以构成一个完整的BPM系统。

 

 

WS-BPEL (Business Process Execution Language) is an XML-based language defining several constructs to write business processes. It defines a set of basic control structures like conditions or loops as well as elements to invoke web services and receive messages from services. It relies on WSDL to express web services interfaces. Message structures can be manipulated, assigning parts or the whole of them to variables that can in turn be used to send other messages. More about the specification can be found on our BPEL page.

 

 

 

The key components of the ODE architecture include the ODE BPEL Compiler, ODE BPEL Engine Runtime, ODE Data Access Objects (DAOs), ODE Integration Layers (ILs), and user tooling. A high-level depiction of the relationships between these components is shown in the Figure below. It can be summarized as: "The compiler converts BPEL documents into a form executable by the run-time, which executes them in a reliable fashion by relying on a persistent store accessible via the DAOs; the run-time executes in the context of an Integration Layer which connects the engine to the broader execution environment ( i.e. the "world").

 

 

Features

1)Side-by-side support for both the WS-BPEL 2.0 OASIS standard and the legacy BPEL4WS 1.1 vendor specification.

2)Supports 2 communication layers: one based on Axis2 (Web Services http transport) and another one based on the JBI standard (using ServiceMix).

3)Support for the HTTP WSDL binding, allowing invocation of REST-style web services.

4)Possibility to map process variables externally to a database table of your choice.

5)High level API to the engine that allows you to integrate the core with virtually any communication layer.

6)Hot-deployment of your processes.

7)Compiled approach to BPEL that provides detailed analysis and validation at the command line line or at deployment.

8)Management interface for processes, instances and messages.