task.js

/**
 * created by maple 2017-01-10
 */
'use strict';

const EventEmitter = require('events').EventEmitter;

const Tigger = require('./lib/trigger');
const ts = require('./lib/timestamp');

module.exports = class Task extends EventEmitter {
  constructor (heartbeatCheckTime, taskExpireTime, defaultTime) {
    super();

    if (typeof heartbeatCheckTime === 'object') {
      const {
        hbCheckTime: _heartbeatCheckTime,
        expireTime: _taskExpireTime,
        defaultTime: _defaultTime
      } = heartbeatCheckTime;

      heartbeatCheckTime = _heartbeatCheckTime;
      taskExpireTime = _taskExpireTime;
      defaultTime = _defaultTime;
    }

    // heartbeatCheckTime
    this.heartbeatCheckTime = heartbeatCheckTime || 10000;
    // taskExpireTime
    this.taskExpireTime = taskExpireTime || 20000;

    // task name list
    this.taskNames = [];
    // task list
    this.tasks = [];
    // task intervalTime list
    this.taskIntervalTimes = [];
    // task heartbeatTime list
    this.heartbeatTimes = [];
    // task tigger list
    this.tiggers = [];
    // task options
    this.taskOptions = [];

    this.defaultTime = defaultTime;
  }

  _startTasks () {
    const self = this;
    // start tasks
    self.taskNames.forEach((taskName, index) => {
      const taskIntervalTime = self.taskIntervalTimes[index];
      const task = self.tasks[index];
      const t = new Tigger(taskIntervalTime);
      const options = self.taskOptions[index];
      t.on('done', () => {
        self.heartbeatTimes[index] = ts.get();
        let beginTime;
        if (options.timing) {
          beginTime = ts.getMs();
        }
        task(() => {
          if (beginTime && options.timing) {
            self.emit('log', `【  TASK  】${taskName} RUN TIME ${ts.getMs() - beginTime} ms`);
          }
        });
        self.emit('log', `【  TASK  】${taskName} START RUN at time ${ts.toLocaleString()}`);
      });
      t.start();
      self.tiggers[index] = t;
    });
  }

  run () {
    // start check tasks
    this._startTasks();
    this.emit('start');
  }

  stop () {
    const tiggers = this.tiggers;
    try {
      for (const t of tiggers) {
        if (!t || typeof t.stop !== 'function') continue;
        t.stop();
        t.removeAllListeners();
      }
    } catch (e) {
      this.emit('error', e);
    }
    this.emit('stop');
  }

  addTask (taskName, task, taskIntervalTime, options) {
    if (typeof taskIntervalTime === 'object') {
      options = taskIntervalTime;
      taskIntervalTime = null;
    }

    // 默认间隔时间
    if (!taskIntervalTime) {
      taskIntervalTime = this.defaultTime;
    }

    if (!taskName || !parseInt(taskIntervalTime)) {
      return this.emit('error', new Error('illegal taskName & intervalTime'));
    }
    if (!task || typeof task !== 'function') {
      return this.emit('error', new Error('task should be function'));
    }
    if (this.taskNames.indexOf(taskName) > -1) {
      return this.emit('error', new Error(`taskName ${taskName} is existed!`));
    }

    this.taskNames.push(taskName);
    this.tasks.push(task);
    this.taskIntervalTimes.push(parseInt(taskIntervalTime));
    this.heartbeatTimes.push(null);
    this.taskOptions.push(options || {});
  }
};