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AMQP 0-9-1 Message Binding v0.3.0 ​

The AMQP message binding defines message-specific properties for AMQP 0-9-1, allowing you to specify content encoding and an application-specific message type.

Overview ​

This binding object provides metadata about the message payload, helping consumers understand how to decode and process it.

Message Properties ​

PropertyTypeDescription
contentEncodingstringA MIME-type encoding for the message content, such as gzip or application/json.
messageTypestringAn application-specific string that describes the message type, e.g., user.signup or order.created.
bindingVersionstringThe version of this binding. For v0.3.0, this MUST be 0.3.0.

Examples ​

Gzip Content Encoding ​

This example specifies that the message payload is compressed using gzip.

yaml
messages:
  userProfile:
    bindings:
      amqp:
        contentEncoding: 'gzip'
        messageType: 'user.profile.update'
        bindingVersion: '0.3.0'

Application-Specific Message Type ​

This example uses messageType to label the event, which helps consumers route or handle the message correctly.

yaml
messages:
  orderEvent:
    bindings:
      amqp:
        messageType: 'order.created.v2'
        bindingVersion: '0.3.0'

Use Cases ​

Content Compression ​

Use contentEncoding to specify that a message payload is compressed (e.g., with gzip) to reduce network bandwidth and storage costs, especially for large payloads.

Message-Driven Logic ​

Use messageType to implement message-driven logic where consumers can inspect this property to decide how to deserialize and process the payload without having to inspect the payload itself.

Event Versioning ​

The messageType property can also be used to version events (e.g., user.created.v1, user.created.v2), allowing for smoother schema evolution and backward compatibility.

Versioning ​

This binding is for version 0.3.0 of the AMQP binding specification.