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It is left for the retrieving registry to choose how to collect the messages, by picking one of the following scenarios:
- Using the endpoint: availableMessages - Retrieve an array with an overview of all the messages that are ready to be downloaded, including sequence numbers
This endpoint allows end users to retrieve an overview of all messages ready to be downloaded, including their corresponding sequence numbers. This information can be used to retrieve the messages from their respective *retrieve endpoints. If desired, the messages can be pulled in chronological order, given by the sequence numbers. Each "retrieve" endpoint will have an optional parameter "sequenceNumber", that allows for an individual collection of the corresponding message(s). If that parameter is left empty all available messages are retrieved (according to the limit set in the parameters).
- Using the endpoint: availableMessagesAll - Retrieve an array of all the messages that are ready to be downloaded, including message content (OPTIONAL, MAY NOT BE IMPLEMENTED)
This endpoint allows end users to retrieve an array of all messages ready to be downloaded, including their content. This would allow a registry to call one single endpoint to collect all messages.
Limitations:
This option does not work for all applications/tooling, like defining custom API connectors in the 365 PowerPlatform. In those cases the same static structure for all call responses on a specific endpoint is not only implementing best practices (IBP), but also required.
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