private async establishConnection()

in src/sinks/connections/TcpClient.ts [87:124]

• 31 lines of code
• 4 McCabe index (conditional complexity)

  private async establishConnection(): Promise<void> {
    await new Promise((resolve, reject) => {
      const onError = (e: Error): void => {
        // socket is already open, no need to connect
        if (e.message.includes('EISCONN')) {
          resolve();
          return;
        }
        LOG('TCP Client received error', e);
        this.disconnect(e.message);
        reject(e);
      };

      const onConnect = (): void => {
        this.socket.removeListener('error', onError);
        LOG('TcpClient connected.', this.endpoint);
        resolve();
      };

      // TODO: convert this to a proper state machine
      switch (this.socket.readyState) {
        case 'open':
          resolve();
          break;
        case 'opening':
          // the socket is currently opening, we will resolve
          // or fail the current promise on the connect or
          // error events
          this.socket.once('connect', onConnect);
          this.socket.once('error', onError);
          break;
        default:
          LOG('opening connection with socket in state: ', this.socket.readyState);
          this.socket.connect(this.endpoint.port, this.endpoint.host, onConnect).once('error', onError);
          break;
      }
    });
  }