AMQP (Advanced Message Queuing Protocol)

Table of contents

  1. Overview
  2. General Frame Format
  3. Method Payloads
  4. Property and Method Summary
  5. Sample Hexdump
  6. Reference

Overview

AMQP (Advanced Message Queuing Protocol) is an open standard for message-oriented communication that enables reliable and interoperable data exchange between distributed systems. It defines a binary protocol for framing, routing, and delivering messages, supporting patterns such as publish/subscribe, request/response, and point-to-point. AMQP ensures features like guaranteed delivery, message acknowledgment, and flexible routing through exchanges and queues, and is widely used in enterprise integration and cloud services.

General Frame Format 

0      1         3         7                size+7     size+8
+------+---------+---------+ +-------------+ +-----------+
| type | channel | size    | |   payload   | | frame-end |
+------+---------+---------+ +-------------+ +-----------+
 octet   short     long        'size' octets     octet

AMQP defines these frame types:
* Type = 1, "METHOD": method frame.
* Type = 2, "HEADER": content header frame.
* Type = 3, "BODY": content body frame.
* Type = 4, "HEARTBEAT": heartbeat frame.

Method Payloads 

0          2           4
+----------+-----------+-------------- - -
| class-id | method-id | arguments...
+----------+-----------+-------------- - -
    short      short   ...

Property and Method Summary

Class ID Short Class Description Method ID Short Method Description
connection 10 work with socket connections start 10 start connection negotiation
      start-ok 11 select security mechanism and locale
      secure 20 security mechanism challenge
      secure-ok 21 security mechanism response
      tune 30 propose connection tuning parameters
      tune-ok 31 negotiate connection tuning parameters
      open 40 open connection to virtual host
      open-ok 41 signal that connection is ready
      close 50 request a connection close
      close-ok 51 confirm a connection close
channel 20 work with channels open 10 open a channel for use
      open-ok 11 signal that the channel is ready
      flow 20 enable/disable flow from peer
      flow-ok 21 confirm a flow method
      close 40 request a channel close
      close-ok 41 confirm a channel close
exchange 40 work with exchanges declare 10 verify exchange exists, create if needed
      declare-ok 11 confirm exchange declaration
      delete 20 delete an exchange
      delete-ok 21 confirm deletion of an exchange
queue 50 work with queues declare 10 declare queue, create if needed
      declare-ok 11 confirms a queue definition
      bind 20 bind queue to an exchange
      bind-ok 21 confirm bind successful
      purge 30 purge a queue
      purge-ok 31 confirms a queue purge
      delete 40 delete a queue
      delete-ok 41 confirm deletion of a queue
      unbind 50 unbind a queue from an exchange
      unbind-ok 51 confirm unbind successful
basic 60 work with basic content qos 10 specify quality of service
      qos-ok 11 confirm the requested qos
      consume 20 start a queue consumer
      consume-ok 21 confirm a new consumer
      cancel 30 end a queue consumer
      cancel-ok 31 confirm a cancelled consumer
      publish 40 publish a message
      return 50 return a failed message
      deliver 60 notify the client of a consumer message
      get 70 direct access to a queue
      get-ok 71 provide client with a message
      get-empty 72 indicate no messages available
      ack 80 acknowledge one or more messages
      reject 90 reject an incoming message
      recover-async 100 redeliver unacknowledged messages
      recover 110 redeliver unacknowledged messages
      recover-ok 111 confirm recovery
tx 90 work with transactions select 10 select standard transaction mode
      select-ok 11 confirm transaction mode
      commit 20 commit the current transaction
      commit-ok 21 confirm a successful commit
      rollback 30 abandon the current transaction
      rollback-ok 31 confirm successful rollback

Sample Hexdump

Protocol Header. The client MUST start a new connection by sending a protocol header. This is an 8-octet sequence:

Advanced Message Queuing Protocol
    Type: Method (1)
    Channel: 0
    Length: 524
    Class: Connection (10)
    Method: Start (10)
    Arguments

0000   41 4d 51 50 00 00 09 01                           AMQP....

Connection.Open

Advanced Message Queuing Protocol
    Type: Method (1)
    Channel: 0
    Length: 8
    Class: Connection (10)
    Method: Open (40)
    Arguments
        Virtual-Host: /
        Capabilities: 
        .... ...1 = Insist: True

0000   01 00 00 00 00 00 08 00 0a 00 28 01 2f 00 01 ce   ..........(./...

Reference

https://github.com/ericwu1997/references/blob/master/amqp-specification.zip