Message Processing

This section covers how to process messages in your microservice handlers, including filtering, handling, and dealing with unhandled messages.

Overview

Message processing is the core of Talon microservice development. Messages arrive on subscribed channels, are filtered and dispatched to handlers, where business logic executes within automatic transactions.

Message Processing Flow

1. Message Arrival - Inbound message arrives on subscribed channel

2. Duplicate Detection - Sequence numbers checked to detect and discard duplicates

3. Filtering - Optional filter determines if message should be processed

4. Handler Dispatch - AEP Engine dispatches to handler based on message type

5. Business Logic - Handler reads message, updates store, creates outbound messages

6. Transaction Commit - Handler returns, transaction commits with consensus

7. Message Acknowledgment - Inbound message acknowledged

Topics

• Detecting Duplicates - Detect and discard duplicate messages using sequence numbers

• Filtering Messages - Use message filters to selectively process messages

• Processing Messages - Core message handling and business logic

  • Handling Messages - Write message handlers

  • Sending Messages - Send outbound messages

• Unhandled Messages - Handle messages with no registered handler

Related Topics

• Message Processing - Conceptual overview

• Transactions - How transactions work

• Registering Message Interest - Subscribe to message channels