Function addHandler

lib/utilities/will-interrupt-process.js:78–94

* Add process interruption handler * * When the first handler is added then automatically * sets up process interruption signals listeners * * @private * @method addHandler * @param {function} cb Callback to be called when process interruption fired

(cb)

   * @param {function} cb   Callback to be called when process interruption fired
   */
  addHandler(cb) {
    if (!_process) {
      throw new Error('process is not captured');
    }

    let index = handlers.indexOf(cb);
    if (index > -1) {
      return;
    }

    if (handlers.length === 0) {
      setupSignalsTrap();
    }

    handlers.push(cb);
    captureExit.onExit(cb);
  },

  /**
   * Remove process interruption handler