Global Class: WebSocketCopy Anchor Link

The WebSocket global class provides a persistent, full-duplex TCP communication channel adhering to RFC 6455. It supports both plain (ws://) and TLS-encrypted (wss://) sockets.

Socket driver source code is maintained in the KryonOS GitHub Repository.

1. ConstructorCopy Anchor Link

new WebSocket(url, protocols)Copy Anchor Link

Creates a new WebSocket connection instance.

• Parameters:
  • url (String): WebSocket target endpoint (e.g. "wss://broker.kryonos.harislab.tech/ws").
  • protocols (String or Array, optional): Sub-protocol string or array of strings.
• Returns: WebSocket instance.

2. Properties & State ConstantsCopy Anchor Link

• ws.readyState (Integer): Current numeric state.
• ws.url (String): Connection URL string.

3. Event CallbacksCopy Anchor Link

Assign JavaScript handler functions to the instance event hooks:

• ws.onopen = function() { ... }: Triggered when the socket completes its handshake.
• ws.onmessage = function(event) { ... }: Triggered upon incoming frame reception (event.data contains string or TypedArray).
• ws.onerror = function(error) { ... }: Triggered on connection errors.
• ws.onclose = function(event) { ... }: Triggered on socket disconnection (event.code, event.reason).

4. MethodsCopy Anchor Link

ws.send(data)Copy Anchor Link

Transmits text or binary data across the active connection.

• Parameters: data (String, ArrayBuffer, or Uint8Array)
• Returns: Boolean (true if buffered/transmitted).

ws.close(code, reason)Copy Anchor Link

Initiates a graceful closing handshake.

• Parameters:
  • code (Integer, optional): Close code (default 1000 for Normal Closure).
  • reason (String, optional): Short closing message.
• Returns: undefined

Code Example: Real-Time Telemetry StreamerCopy Anchor Link

// Connect to remote WebSocket broker
var ws = new WebSocket("wss://echo.websocket.events");

ws.onopen = function() {
  System.print("WebSocket connected successfully!");
  
  // Send device handshake
  ws.send(JSON.stringify({
    event: "device_ready",
    uptime: System.millis(),
    heap: System.getInfo().freeRAM
  }));
};

ws.onmessage = function(event) {
  System.print("Received message: " + event.data);
  
  try {
    var cmd = JSON.parse(event.data);
    if (cmd.action === "reboot") {
      System.restart();
    }
  } catch(e) {}
};

ws.onerror = function(err) {
  System.print("WebSocket error occurred: " + err);
};

ws.onclose = function(evt) {
  System.print("WebSocket closed (code " + evt.code + ")");
};