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The actual messages have to be collected via individual API calls against the different "retrive" APIs. In order to streamline that process a "master"-retrieve API (/api/v2/availableMessages) is provided that returns a list of individual "retrieve" APIs that contain waiting messages for the retrieving registry. The availableMessages API will list per "retrive" API the sequence number(s) of the waiting message(s) in an array. Each "retrive" API will have the optional parameter "sequenceNumber", that allows for an indivual collection of that specific message. If that parameter is left empty all available messages are retrieved (according to the limit set in the parameters).
It is left for the retrieving registry to choose how to collect the messages:
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