What role does ZMQ play in services?

[FFXI-Dev]

I saw the world server forwarding messages in the log. Does the world server message exist in ZMQ? Which service started ZMQ? What is the port on the ZMQ server and how is it linked?

[FFXI-Dev]

What mode do they use? Publish subscription?

[zach2good]

We use ROUTER/DEALER sockets between our different processes. xi_world holds the ROUTER and the other processes each have a DEALER.

The port is defined in the settings under network.ZMQ_PORT. All the processes read from and use this setting, so you can change this if you want .There's little need to unless you have other unrelated ZMQ things happening on that port.

You can find the central hub of our ZMQ messaging here: https://github.com/LandSandBoat/server/blob/base/src/world/message_server.cpp#L360

and for the other processes:
https://github.com/LandSandBoat/server/blob/base/src/map/message.cpp#L904

[FFXI-Dev]

Will DEALER consume messages in ZMQ's ROUTER/DEALER mode (which would result in other consumers not being able to access the messages)? I plan to create a page that displays different messages for listening (can these messages be processed without the AntoTranslate to obtain clear text). Is this feasible?

[zach2good]

ZMQ messaging is for communication between server processes, only about 30% of this is passing messages between players. There's also the caveat that messages between players hosted on the same process won't go through ZMQ. If you wanted to display text messages between players you'd need to look at the chat message packet handler in packet_system.

Autotranslate in text messages is a collection of 4x bytes, which are used as a lookup by the client in the DAT files. We have them partially mapped out in autotranslate.cpp, and another open PR here: #3626

[zanglikun]

Do ZMQ have a client? I would like to see what the message looks like. So that I can use other programming languages to process some data. @zach2good

[zach2good]

Please don't tag me directly.

You can see interaction with ZMQ with python with this script: https://github.com/LandSandBoat/server/blob/base/tools/announce.py

The message comes in here: https://github.com/LandSandBoat/server/blob/base/src/map/message.cpp#L904

and is then forwarded here: https://github.com/LandSandBoat/server/blob/base/src/map/message.cpp#L904

The documents for ZMQ are very very good, make sure you read them: https://zguide.zeromq.org/docs/chapter1/