Chat

Chat is a very simple service to implement, all it does is receive messages, and then forward them on to all other (not including the sender) clients.
It used to power the chat pane in the workspace, but doesn't anymore. Now it just powers multiplayer for .draw files.

Implementation & Messages

The chat service only deals with one message type, ChatMessage. Here is an example message that a client could send to the server:

{
    "chatMessage": {
        "username": "replbot",
        "text": "hello from replbot!"
    }
}

The server would then send the message along to all other connected clients.

Some info from the old developer docs.