Function getVscodeBridge

vscode/src/webview/vscodeBridge.ts:23–114

()

let cachedBridge: VscodeBridge | null = null;

export function getVscodeBridge(): VscodeBridge {
  if (cachedBridge) {
    return cachedBridge;
  }

  const traceId =
    (document.body && document.body.dataset && document.body.dataset.muxTraceId) || "unknown";

  let vscode: { postMessage: (data: unknown) => void };
  try {
    // eslint-disable-next-line @typescript-eslint/ban-ts-comment
    // @ts-ignore VS Code injects this in the webview
    vscode = acquireVsCodeApi();
  } catch (error) {
    throw new Error(`mux webview: acquireVsCodeApi failed: ${String(error)}`);
  }

  const startedAtMs = Date.now();
  let nextSeq = 1;

  const listeners = new Set<(data: unknown) => void>();

  const onMessage = (handler: (data: unknown) => void): (() => void) => {
    listeners.add(handler);
    return () => {
      listeners.delete(handler);
    };
  };

  window.addEventListener("message", (event: MessageEvent) => {
    for (const handler of listeners) {
      try {
        handler(event.data);
      } catch (error) {
        // eslint-disable-next-line no-console
        console.error("mux webview: message handler crashed", error);
      }
    }
  });

  const postMessage = (payload: WebviewToExtensionMessage): void => {
    assert(payload && typeof payload === "object" && "type" in payload, "postMessage requires a payload with type");

    const meta = {
      traceId,
      seq: nextSeq++,
      sentAtMs: Date.now(),
      sinceStartMs: Date.now() - startedAtMs,
    };

    const envelope: Record<string, unknown> = { __muxMeta: meta, ...payload };
    vscode.postMessage(envelope);
  };

  const debugLog = (message: string, data?: unknown): void => {
    // Mirror to DevTools console.
    // eslint-disable-next-line no-console
    console.log(`[mux-webview ${traceId}] ${message}`, data);