Introduction to Synchronous Interactions

5-4 Oracle Fusion Middleware Developers Guide for Oracle SOA Suite Figure 5–3 provides an overview. Figure 5–3 Asynchronous Interaction BPEL Process Service Component as the Client When the BPEL process service component is on the client side of an asynchronous transaction, it needs an invoke activity to send the request and a receive activity to receive the reply. As with all partner activities, the WSDL file defines the interaction. BPEL Process Service Component as the Service As with a synchronous transaction, when the BPEL process service component is on the service side of an asynchronous transaction, it needs a receive activity to accept the incoming request and an invoke activity to return either the requested information or a fault. Note the difference between this and responding from a synchronous BPEL process: a synchronous BPEL process uses a reply activity to respond to the client and an asynchronous service uses an invoke activity. For more information about asynchronous interactions, see Chapter 8, Invoking an Asynchronous Web Service from a BPEL Process.

5.4 Introduction to Asynchronous Interactions with a Timeout

In an asynchronous interaction with a timeout which you perform in BPEL with a pick activity, a client sends a request to a service and waits until it receives a reply, or until a certain time limit is reached, whichever comes first. For example, a client requests a loan offer. If the client does not receive a loan offer reply within a specified amount of time, the request is canceled. Figure 5–4 provides an overview. Client BPEL Process WSDL PartnerLink d2 Service BPEL Process invoke Get response receive receive d1 Call service invoke Introduction to Interaction Patterns in a BPEL Process 5-5 Figure 5–4 Asynchronous Interaction with Timeout BPEL Process Service Component as the Client When the BPEL process service component is on the client side of an asynchronous transaction with a timeout, it needs an invoke activity to send the request and a pick activity with two branches: an onMessage branch and an onAlarm branch. If the reply comes after the time limit has expired, the message goes to the dead letter queue. As with all partner activities, the WSDL file defines the interaction. For more information about asynchronous interactions with a timeout, see Section 14.2, Creating a Pick Activity to Select Between Continuing a Process or Waiting. BPEL Process Service Component as the Service The behavior of the BPEL process service component as a service matches the behavior with the asynchronous interaction with the BPEL process service component as the service.

5.5 Introduction to Asynchronous Interactions with a Notification Timer