message-channel

Message Channel (message-channel)

This example demonstrates using MessageChannel (via MessageClient) for peer messaging without media publish/subscribe.

Under the hood, the SDK negotiates a WebRTC connection with a data channel and uses it for chat-style communication only (no camera/microphone video pipeline required for core messaging).

What This Example Demonstrates

• data-channel-only messaging client flow
• opening/closing a message channel session
• configurable RTCDataChannel options (name, ordered/unordered, retransmit/lifetime modes)
• JSON text chat messaging between peers
• optional binary audio snippet send/receive over the same data channel

Core Behavior

1. User configures DataChannel settings.
2. App creates a dynamic stream name from DataChannel name + random suffix.
3. MessageChannel.init(...) is called with includeDataChannel: true.
4. open() establishes the channel.
5. Peer messages are sent/received through DataChannel events.

Minimal Developer Snippet

const channel = new red5prosdk.MessageChannel()

channel.on('*', (event) => {
  if (event.type === red5prosdk.MessageChannelEventTypes.RECEIVE) {
    console.log('Message received', event.data)
  }
})

await channel.init({
  endpoint,
  streamName,
  includeDataChannel: true,
  dataChannelConfiguration: {
    name: 'red5pro',
    ordered: true,
  },
})

await channel.open()
await channel.send(JSON.stringify({ message: 'hello' }))

Peer Testing Pattern

The example includes an Open Chat Peer link that opens another message-channel instance.
Use two tabs/windows to validate send/receive behavior between peers.

Endpoint and connectionParams: Standalone vs Stream Manager

MessageChannel endpoint setup follows the same environment rules as other SDK clients, while still focusing on data-channel-only messaging behavior.

Standalone Server

const endpoint = `https://${host}:443/live/whip/${streamName}`
const connectionParams = {}

Stream Manager

const endpoint = `https://${host}/as/v1/proxy/whip/${app}/${streamName}`
const connectionParams = {
  // e.g. region, nodeGroup, auth metadata
}

Where to Look in This Example

• channel open flow: startChannel()
• channel close flow: stopChannel()
• channel event handling: onChannelEvent()
• JSON send flow: sendJsonMessage()
• binary message flow: startBinaryMessageRecording() and handleMessageChannelReceive()
• DataChannel form wiring: src/lib/data-channel-configuration.ts

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Use this example as the baseline for adding lightweight chat/messaging capabilities through Red5 Pro data channels when media streaming is not required.