Service operations
When a service instance is added successfully to the application, using the Diffusion management console or by using a configuration file, it will be in an active state, meaning that the service is publishing to or consuming from Diffusion topics as expected.
The framework allows each active service to be paused and resumed using the Diffusion management console. It is also possible to pause the whole application, which pauses all services in the application.
The operations available on running Gateway application can be viewed in the Diffusion management console which are: Pause, Resume and Shutdown. For services, the operations are Pause and Resume.
Pause Operation
When a service instance is paused, data are neither published to Diffusion topics nor data from Diffusion topics are processed/published to an external system.
Other than a service being paused by a user via Diffusion management console, there are two more reasons for a service to be paused, which are:
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If the framework loses its connection to Diffusion server
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If the application reports that a severe issue has occurred by setting a RED status for a service
Resume Operation
Corresponding to reasons for a service to be paused, there are three reasons for it to be resumed and activated. They are:
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Resuming via Diffusion management console
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If the connection to Diffusion service re-establishes
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If the application reports that the issue is resolved by setting GREEN status for the service
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It is possible for a service to be paused for more than one
reason. For example, if an application reported a RED status, and
then the connection to Diffusion was lost. In this case, even if the application
reports a GREEN status, the service will not be resumed until the
connection has been re-established. The service would be only resumed if the connection to Diffusion server re-establishes.
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