Raghav-B / NUS_RoboMaster_Signalling_Server

Signalling Server for WebRTC-based remote control of NUS RoboMaster's robots.

webRTC Signalling Server for Real-Time Robot Control

This server handles signalling for webRTC connection requests from a client on a device to a remotely controlled robot.

Setup for Full Signalling Server

• Install nodejs
• Setup TURN server using coTURN with the following instructions.
  • This is needed by webRTC to go through firewalls. Both the client frontend and robot need to know the IP:port for this server
• Run the script using the node server.js command

Setup for Local Testing

• Only requires running the script using node server.js

Function Reference

###robotLoginHandler(data, connection)

Use When a robot switches on, it sends a connection request that triggers this function. The function saves the robot information in an object/map called connectedRobots with the key as the robot name and the value being the robot connection object. It also appends a joinedGame parameter to the connection object to signify which game this robot is available to clients under.

Parameters data: Object of format:

{ 
    type: "robot-login", 
    name: <RobotNameString>,        // Unique identifier for robot
    joinedGame: "<GameNameString>   // Which game this robot will be available under
}

connection: The robot connection object returned by WebSocket

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###userLoginHandler(data, connection) Use When a client logs into the frontend from their browser, this function is called. It stores the client data in an object/map called connectedUsers with the key as the user name and the value being the user connection object. This data is later used by other functions to link up a robot and client together in a webRTC stream. It also performs a check if a user has entered a duplicate username as another user already connected.

Parameters data: Object of format:

{ 
    type: "user-login",     
    name: <UserNameString>, // Unique identifier for user (previously entered by user in frontend)
}

connection: The user connection object returned by WebSocket

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The other functions follow the same design pattern as above, where they are called from a single switch/case statement depending on what query the user has entered.