LAST MODIFIED: 13-Nov-1998

The message service publishes messages originating from other software components. It is the only component of the architecture that is allowed to transmit messages to the outside world. The service filters messages according to their severity and dispatches them to different output destinations (such as the process' standard output and standard error streams, an error logging facility, the detector control system etc.).

A given message may be generated several times. The message service can count messages of a given type; it may filter out duplicate occurrences of a given message.

The type of filtering and the selection of output destinations is configurable via job options.

In the initial implementation there will be only two possible output destinations (standard output and standard error)

Interfaces

• IMessage interface. This interface is used by clients wishing to report a message to the MessageSvc.

• IMsgLogger interface. This interface is used to dispatch messages to message logging clients. This interface will not be implemented in the initial version of the MessageSvc
  
• IsetProperty interface. The message service must implement this interface in order to be configured

Dependencies and requirements

• Message severity levels must be uniquely defined throughout the system
  
• Message types must be identified by a unique combination of facility code and error number
  .
• Message sources (and destinations) must be uniquely identified.