Relay-WS

Warning

This project is neither stable nor actively developed.

Simple and minimalistic WebRTC signalling server based on WebSocket.

How to use

Docker

$ docker buildx build -t <tag> -o type=docker .
$ docker run -dp 34098:34098 <tag>

Docker Compose

$ docker compose up -d

Build manually

$ corepack enable
$ pnpm install
$ pnpm build
$ pnpm run start

How relay server works

sequenceDiagram
    autonumber
    actor pc1 as Peer 1
    participant sig as Relay Server
    actor pc2 as Peer 2
    pc1->>sig: Peer 1 Join
    Note over sig: Assign Unique ID for Peer 1:<br><peer1>
    pc1->>+sig: type: ls
    sig--)-pc1: peers: []
    pc2->>sig: Peer 2 Join
    Note over sig: Assign Unique ID for Peer 2:<br><peer2>
    pc2->>+sig: type: ls
    sig--)-pc2: peers: [<peer1>]
    pc2->>+sig: type: offer, to: <peer1>
    sig--)-pc1: type: offer, from: <peer2>
    pc1->>+sig: type: answer, to: <peer2>
    sig--)-pc2: type: answer, from: <peer1>
    loop ICE Candidate Exchange
        par Candidate from Peer 1
            pc1->>+sig: type: ice, to: <peer2>
            sig--)-pc2: type: ice, from: <peer1>
        and Candidate from Peer 2
            pc2->>+sig: type: ice, to: <peer1>
            sig--)-pc1: type: ice, from: <peer2>
        end
    end
    pc1-->>+sig: type: leave
    Note over pc1: Peer 1 exits
    par Broadcase
        sig--)-pc2: type: leave, from: <peer1>
    end
    pc2-->>sig: type: leave
    Note over pc2: Peer 2 exits

Message table

List

Request

Name	Type
type	"ls"

Response

Name	Type
type	"ls"
peers	ID[]

Leave

Request

Name	Type
type	"leave"

Response

Name	Type
type	"leave"
from	ID

Offer

Request

Name	Type
type	"offer"
to	ID
sdp	string

Response

Name	Type
type	"offer"
from	ID
to	ID
sdp	string

Answer

Request

Name	Type
type	"answer"
to	ID
sdp	string

Response

Name	Type
type	"answer"
from	ID
to	ID
sdp	string

ICE candidate

Request

Name	Type
type	"ice"
to	ID
sdp	string

Response

Name	Type
type	"ice"
from	ID
to	ID
sdp	string