Implementing Event Hubs SDK over AMQP 1.0

[minghuaw]

This is the initial attempt at implementing the EventHubs sdk over AMQP 1.0 protocol in rust. The overall approach is very similar to the Service Bus over AMQP PR (#1185), which essentially follow what the dotnet SDK does. There is one minor distinction though, which is that all public methods that returns a Result try to use azure_core::Error instead of custom enums. This minor distinction will be adopted by #1185 later.

Scope

What has been implemented in this PR

Not all features are implemented. Below is a list of the features that are included in this PR.

Feature checklist (this will be updated over time):

• EventHubConnection
  • Get Event Hub properties
  • Get partition properties
  • Automatic recovery
• EventHubProducerClient
  • create from connection string
  • (won't implement) send_idempotent
    This is NOT implemented because (1) the underlying AMQP 1.0 sender already takes care of keeping track of unsettled deliveries (2) the current design take the ownership of event/message, making storing things like pending_sequence_no useless
  • create and send EventBatch
  • Get Event Hub properties
  • Get partition properties
  • Automatic recovery
• EventHubConsumerClient
  • create from connection string
  • receive from partition
  • receive from all partition
    Closing the AMQP receivers currently uses a temporary workaround which simply drops all receivers and their sessions. The workaround is acceptable because the internal states of AMQP Sender and Session (not Sender itself but its inner state) implements the Drop trait which performs proper exchange of Detach/End frames upon dropping.
  • auto-recovery
  • impl Stream
• PartitionReceiver

What will be implemented in future PRs?

• EventHubBufferedProducerClient
• EventHubProcessor
• CheckpointStore and BlobCheckpointStore
• Support for wasm32 targets

[cataggar]

Hi @minghuaw,

Those of us volunteering on this project really like seeing this work. However, for now, I think it is best suited in an another repository.

https://crates.io/crates/azeventhubs