FIMS Media SOA Framework - AMWA

FIMS Media SOA Framework Phase1 (Preliminary)If an error is detected during the execution of a long-running process (e.g. Job Ended with Failure) and thefaultTo parameter has been set in the request message, then an error notification message shall be sent to thedestination specified by faultTo.The client may also retrieve the status of the failed operation by polling the service. The service shall provide aresponse message with the status indicating the operation failed and the associated fault information.6.2.4 Failure RecoveryA service failure during the execution of a workflow should be a recoverable process. The framework allows forthe retry of the failed service since in many cases the cause of the failure can be easily fixed by humanintervention. In this scenario the workflow is paused at the invocation of the failed service and can be restartedmanually after the service is fixed.The framework also allows for the definition of a compensation mechanism in the workflow to rollback to a welldefined condition when the failure cannot be recovered by a simple retry mechanism.6.2.5 Job QueueA service may implement a queue to support multiple simultaneous requests. If implemented, job requests arefirst en-queued in the order of priority and arrival. The service de-queue the jobs and processes them one byone. Multiple jobs can be de-queued at once if the service supports the execution of multiple simultaneous jobs(multi-threading).The figure below shows the states associated to the job queue and the transitions initiated by the queuecommands issued to the service. The states are associated to the processes that en-queue (accepts new jobs)and de-queue (starts execution of an en-queued job) requests. The Started state means that both the enqueuingand de-queuing processes are active. Locked means jobs cannot be en-queued but they are still beingde-queued. Stopped means jobs are not being either en-queued or de-queued.Private committee documentWorking Draft for review by FIMS Rev v1, Nov-16-2010 Page 21 of 89