Oracle SOA Dynamic Service Call Framework By Kathiravan Udayakumar

Transcription

1 Oracle SOA Dynamic Service Call Framework By Kathiravan Udayakumar Dynamic Service call Framework is very critical and immediate requirement of most of SOA Programs and SOA Implementation. Such as framework, is required to migrate existing and as well as the new use cases on to Oracle SOA Platform. Making decision at runtime to call appropriate function or operation to accomplish the required task is not new use case in SOA; the need is well felt before in Object Oriented Programming as well. Object Oriented Programs that are well known to us such as Java has provide the interfaces for design time and makes dynamic calls to required implementation through required binding at runtime. SOA also uses similar principles to make the Dynamic Service Call. This article will explain in detail about the need for Dynamic Service Call framework and implementation details. Framework Summary Dynamic Calls to WebServices can be achieved through WS-Addressing standards and Dynamic Partner links. To implement SOA Dynamic Service call Framework the configuration should be maintained in a web tool; in this case Oracle DVM (Domain Value Map) or Oracle Business Rules can also be used to configure the dynamic service configuration. The below diagram shows the overall dynamic service call framework; required endpoint adapter wrapper services are built to call the appropriate end points. Decision to call the required service at runtime is determined through the dynamic service call configuration.

2 Component Details From the above diagram, readers can identify the below listed components required for this Framework. 1. Dynamic Service Call Configuration Web Application 2. Dynamic Service Call Configuration Read Service 3. Dynamic Service Call End Point Wrappers Services Components a. DB End Point Wrapper (DynamicDBWriteService) b. File End Point Wrapper (DynamicFileWriteService) c. FTP End Point Wrapper (DynamicFTPWriteService) d. MQ End Point Wrapper (DynamicIBMMQCallService) e. JMS End Point Wrapper (DynamicWJMSCallService) f. Web Service End Point Wrapper (WebServiceAdapter) g. AQ End Point Wrapper (Not shown in this diagram) Component Description Dynamic Service Call Dynamic Service Call Configuration Web Tool/Application would aid the readers to store the required end point configuration for the incoming message. Based on the incoming message (into framework) and configuration

3 Configuration Web Application completed the web tool the required end point would be called from the framework. This configuration can be stored using a DVM as well; it would reduce the overhead in creating and maintain this application. It would also help to make calls from SOA Applications; downside this configuration will not be available from other application services. Dynamic Service Call Configuration Read Service Dynamic Service Call Configuration Read Service would be web service implementation that read the configuration from the web tool. DB End Point Wrapper DB End Point Wrapper Service is used to call the actual DB message) type that needs to be implemented by all DB End Point Service. File End Point Wrapper (DynamicFileWriteService) FTP End Point Wrapper (DynamicFTPWriteService) MQ End Point Wrapper (DynamicIBMMQCallService) JMS End Point Wrapper (DynamicWJMSCallService) Web Service End Point Wrapper (WebServiceAdapter) File End Point Wrapper Service is used to call the actual File message) type that needs to be implemented by all File End Point Service. All Parameters required for this service can be configured in the End Point Configuration file. FTP End Point Wrapper Service is used to call the actual FTP message) type that needs to be implemented by all FTP End Point Service. All Parameters required for this service can be configured in the End Point Configuration file. MQ End Point Wrapper Service is used to call the actual MQ message) type that needs to be implemented by all MQ End Point Service. All Parameters required for this service can be configured in the End Point Configuration file. JMS End Point Wrapper Service is used to call the actual MQ message) type that needs to be implemented by all JMS End Point Service. All Parameters required for this service can be configured in the End Point Configuration file. Web Service End Point Wrapper Service is used to call the actual MQ End Point Service. It defines an interface (input and out message) type that needs to be implemented by all WebService End Point Service.

4 AQ End Point Wrapper AQ End Point Wrapper Service is used to call the actual MQ message) type that needs to be implemented by all JMS End Point Service. All Parameters required for this service can be configured in the End Point Configuration file. Any additional parameters required for this service can be configured in the End Point Configuration file. Dynamic Service Call Configuration Web Application Dynamic Service Call for the Framework can be configured using the below list of Parameters. Based on the incoming message to the framework, required end point would be called. Read Service Component would aid to read the configuration completed using this application. 1. Application 2. Components 3. Business Object Name 4. Adapter Type 5. End Point URL 6. End Point Properties Dynamic Service Call Implementation The snapshot below shows the list of steps required to implement a dynamic service call.

5 Overriding the Partner Link References - Options: Using a Literal to Construct an Endpoint Using an Existing Partner Link's Endpoint Using an Incoming Message to Extract the Endpoint Using a Database Query to Provide an Endpoint Using a DVM to obtain the Endpoint Using a Business Rules to obtain the Endpoint Using a Service to Obtain the Endpoint. Dynamic Service Call Implementation through BPEL WebService Name and Partner Link name can be changed using the variables by lookup on the service configuration. Partner Link should be created as reference in the composite to be invoked by the overridden WebService Address at runtime. Below code snippet shows the runtime code that should be placed in BPEL to change the WebService. Listing 1: The below code shows the End-Point Reference assignment. <copy> <from> <EndpointReference xmlns=" <Address>[[WebserviceAddress]]</Address> </EndpointReference> </from> <to partnerlink="[[partnerlinkname]]"/> </copy> Note: Dynamic Addressing is only implemented for SOAP (HTTP Binding Component). Dynamic Service Call Implementation through Mediator Dynamic routing of service to different end point adapter service can be achieved through Mediator dynamic routing rule configuration.

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