what is STOMP?

[eubnara]

https://stomp.github.io/stomp-specification-1.2.html

[eubnara]

I found the usage at https://github.com/hortonworks/ambari-release/tree/AMBARI-2.7.3.2-19-tag

[eubnara]

STOMP is a very simple and easy to implement protocol, coming from the HTTP school of design; the server side may be hard to implement well, but it is very easy to write a client to get yourself connected. For example you can use Telnet to login to any STOMP broker and interact with it!

The server side may be hard to implement well.

[eubnara]

STOMP 1.2 Released on 10/22/2012

[eubnara]

frame HTTP command optional headers / body text / binary encoding: UTF-8 / other

[eubnara]

STOMP

• design philosophy
  • simplicity
  • interoperability
• text-based
  • binary message also OK
  • UTF-8 encoding (default)
• frame-based
  • with frames modelled on HTTP
  • frame = command + headers + body
  • HTTP frame != data link layer frame
• It doesn't define what the delivery (message exchange) semantics of destinations should be.
  • It can vary from server to server and even from destination to destination
  • This allows servers to be creative with the semantics that they can support with STOMP.
• STOMP client
  • producer
  • send messages to a destination on the server via a SEND frame.
  • client
  • send a SUBSCRIBE frame for a given destination
  • receive messages from the server as MESSAGE frames.

STOMP frames

A frame's structure

COMMAND
header1:value1
header2:value2

Body^@

• case sensitive

Body

• Only the SEND, MESSAGE, and ERROR frames MAY have a body.
• All other frames MUST NOT have a body.

Connecting

• send CONNECT or STOMP (used in STOMP 1.2 or some 1.1) frame to server
• send CONNECTED or ERROR frame to client

Client Frames

SEND
SUBSCRIBE
UNSUBSCRIBE
BEGIN
COMMIT
ABORT
ACK
NACK
DISCONNECT

SEND frame

SEND
destination:/queue/a
content-type:text/plain

hello queue a
^@

SEND supports a transaction header which allows for transactional sends.

[eubnara]

참고: http://jmesnil.net/stomp-websocket/doc/

ambari 에서는 STOMP endpoint 가 다음과 같은데 왜 websocket 을 썼을까?

wss://{ambari_host_name}:8441/agent/stomp/v1