Method close

packages/socket.io/lib/index.ts:822–851

* Closes server connection * * @param [fn] optional, called as `fn([err])` on error OR all conns closed

(fn?: (err?: Error) => void)

   * @param [fn] optional, called as `fn([err])` on error OR all conns closed
   */
  public async close(fn?: (err?: Error) => void): Promise<void> {
    await Promise.allSettled(
      [...this._nsps.values()].map(async (nsp) => {
        nsp.sockets.forEach((socket) => {
          socket._onclose(class="st">"server shutting down");
        });

        await nsp.adapter.close();
      }),
    );

    this.engine.close();

    class="cm">// restore the Adapter prototype, when the Socket.IO server was attached to a uWebSockets.js server
    restoreAdapter();

    if (this.httpServer) {
      return new Promise<void>((resolve) => {
        this.httpServer.close((err) => {
          fn && fn(err);
          if (err) {
            debug(class="st">"server was not running");
          }
          resolve();
        });
      });
    } else {
      fn && fn();
    }
  }

  /**
   * Registers a middleware, which is a function that gets executed for every incoming {@link Socket}.