GeoDR preparation - EventHubs Offset is a string, not an integer encoded as a string

[LarryOsterman]

Treat Offset fields in Event Hubs as strings, not integers.

With the upcoming GeoDR functionality in Event Hubs, the Offset field needs to contain string data to handle BCDR recovery scenarios.

This change updates the Event Hubs client to respect the on-the-wire encoding of the Offset field rather than attempting to treat the Offset field as an integer type. It also only allows encoding the Offset field as a string, any other encoding is ignored.

GitHub Copilot Summary

This pull request includes multiple changes to the Azure Event Hubs SDK, focusing on modifying the Offset type from numeric to string across various components. The changes span multiple files and include updates to the implementation, tests, and constants.

Changes to Offset Type:

• sdk/eventhubs/azure-messaging-eventhubs-checkpointstore-blob/src/blob_checkpoint_store.cpp: Updated UpdateCheckpointImpl and CreateCheckpointBlobMetadata to handle Offset as a string instead of converting it to a numeric type. [1] [2]

• sdk/eventhubs/azure-messaging-eventhubs/inc/azure/messaging/eventhubs/models/checkpoint_store_models.hpp: Changed Offset type from Azure::Nullable<int64_t> to Azure::Nullable<std::string> in the Checkpoint model.

• sdk/eventhubs/azure-messaging-eventhubs/inc/azure/messaging/eventhubs/models/event_data.hpp: Modified Offset type from Azure::Nullable<std::uint64_t> to Azure::Nullable<std::string> in the EventData model.

• sdk/eventhubs/azure-messaging-eventhubs/src/event_data.cpp: Adjusted the handling of Offset to treat it as a string and updated the annotation key from OffsetNumberAnnotation to OffsetAnnotation.

• sdk/eventhubs/azure-messaging-eventhubs/src/private/eventhubs_constants.hpp: Renamed OffsetNumberAnnotation to OffsetAnnotation to reflect the change in type.

Test Updates:

• sdk/eventhubs/azure-messaging-eventhubs-checkpointstore-blob/test/ut/blob_checkpoint_store_test.cpp: Updated test cases to use string values for Offset instead of numeric values. [1] [2] [3]

• sdk/eventhubs/azure-messaging-eventhubs/test/ut/event_data_test.cpp: Modified tests to expect Offset as a string and removed tests that checked numeric offsets. [1] [2] [3]

• sdk/eventhubs/azure-messaging-eventhubs/test/ut/round_trip_test.cpp: Changed the startOffset type to string in the round trip test.

These changes ensure that the Offset type is consistently treated as a string across the Azure Event Hubs SDK, simplifying the handling of offsets and aligning with the expected data format.

[Copilot]

Copilot reviewed 14 out of 14 changed files in this pull request and generated no comments.

[azure-sdk]

API change check

API changes are not detected in this pull request.