Service Facade to WebSphere MQ: one-way with acknowledgment pattern

Use the Service Facade to WebSphere MQ: one-way with acknowledgment pattern to present a web service interface to clients and to fulfill the service requests by using a WebSphere MQ enabled application.

Use this pattern to bridge the asynchronous HTTP protocols and reliable messaging protocols to handle updates with an assurance that requests are saved for processing.

This pattern provides loose coupling between requesters and providers in timing, protocols, and transport. It is appropriate for service interfaces to existing systems.

A diagram showing the behavior of the pattern. Service requests from clients are placed on a queue for processing and an acknowledgment is then returned.

Solution

The solution is to implement a message flow that provides a service entry point. When a web service request is received over HTTP the data is placed as a persistent message on a queue for the provider application. When the message is placed, an acknowledgment is returned to confirm that the request has been accepted. If a client receives an acknowledgment, the message has been written to the queue. If a fault is received, no message has been sent, however, if the fault is a time out, the case is indeterminate, but client applications are aware that a problem exists.

Request flow
Error subflow
Log subflow

Related tasks

Read the following section for information about how to apply and use this pattern.

Constraints on the use of the pattern
Tasks to complete before applying the pattern
Resources to get you started with the pattern
Interface example
Parameters for the pattern
Tasks to complete after generating the pattern