Create the EventBatch infrastructure

[jsquire]

Summary

Historically, Event Hubs has allowed a batch of events with specified size limit to be prepared using a TryAdd-style interface. Because the size depends on the format of an event and event batch container as it would be transmitted, it is subject to change with the underlying transport and depends on the format used by that transport. Preview two will reintroduce this concept for the AMQP transport, using this as an opportunity to bring the message translation foundation forward from the track one implementation into track two.

Scope of Work

• Implement the EventBatch type, allowing for a size-limited batch to be created.

• Add an API to the producer to allow a new batch to be created, since it is bound to the transport, this creation must be done by the transport-specific client.

• Translate and adapt the track one code for AMQP message translation from the EventData format, along with associated tests.

Out of Scope

• Changes to any references within the TrackOneClient code; that will remain as-is.

• Implementing the actual sending of event batches through the producer and the track two->track one translation of the EventDataBatch; that will be covered under a dedicated workstream.

Success Criteria

• The EventHubProducer can create an EventHubBatch on request, with options configured to limit the size.

• The EventHubBatch can adequately represent its size needed to be published; event data is translated to its wire format for AMQP to be measured.

• The requisite tests have been implemented.