Function connectToDevTools

packages/react-devtools-core/src/backend.js:78–326

(options: ?ConnectOptions)

}

export function connectToDevTools(options: ?ConnectOptions) {
  const hook: ?DevToolsHook = window.__REACT_DEVTOOLS_GLOBAL_HOOK__;
  if (hook == null) {
    // DevTools didn't get injected into this page (maybe b'c of the contentType).
    return;
  }

  const {
    host = 'localhost',
    nativeStyleEditorValidAttributes,
    useHttps = false,
    port = 8097,
    websocket,
    resolveRNStyle = (null: $FlowFixMe),
    retryConnectionDelay = 2000,
    isAppActive = () => true,
    onSettingsUpdated,
    isReloadAndProfileSupported = getIsReloadAndProfileSupported(),
    isProfiling,
    onReloadAndProfile,
    onReloadAndProfileFlagsReset,
  } = options || {};

  const protocol = useHttps ? 'wss' : 'ws';
  let retryTimeoutID: TimeoutID | null = null;

  function scheduleRetry() {
    if (retryTimeoutID === null) {
      // Two seconds because RN had issues with quick retries.
      retryTimeoutID = setTimeout(
        () => connectToDevTools(options),
        retryConnectionDelay,
      );
    }
  }

  if (!isAppActive()) {
    // If the app is in background, maybe retry later.
    // Don't actually attempt to connect until we're in foreground.
    scheduleRetry();
    return;
  }

  let bridge: BackendBridge | null = null;

  const messageListeners = [];
  const uri = protocol + '://' + host + ':' + port;

  // If existing websocket is passed, use it.
  // This is necessary to support our custom integrations.
  // See D6251744.
  const ws = websocket ? websocket : new window.WebSocket(uri);
  ws.onclose = handleClose;
  ws.onerror = handleFailed;
  ws.onmessage = handleMessage;
  ws.onopen = function () {
    bridge = new Bridge({
      listen(fn) {