azkaban webserver代码剖析

  /**
   * Constructor
   */
  public AzkabanWebServer(Server server, Props props) throws Exception {
    this.props = props;
    this.server = server;
    velocityEngine =
        configureVelocityEngine(props
            .getBoolean(VELOCITY_DEV_MODE_PARAM, false));
    sessionCache = new SessionCache(props);//SessionCache是用来保存session的,google.common.Cache
    userManager = loadUserManager(props);//加载用户管理类,默认是XmlUserManager,可以实现UserManager接口,

    alerters = loadAlerters(props);

    executorManager = loadExecutorManager(props);//executor管理器,获取所有executor,更新executor,获取executor整在跑的flow,获取当前flow在跑的个数等
    projectManager = loadProjectManager(props);

    triggerManager = loadTriggerManager(props);
    loadBuiltinCheckersAndActions();

    // load all trigger agents here
    scheduleManager = loadScheduleManager(triggerManager, props);

    String triggerPluginDir =
        props.getString("trigger.plugin.dir", "plugins/triggers");

    loadPluginCheckersAndActions(triggerPluginDir);

    baseClassLoader = this.getClassLoader();

    tempDir = new File(props.getString("azkaban.temp.dir", "temp"));

    // Setup time zone
    if (props.containsKey(DEFAULT_TIMEZONE_ID)) {
      String timezone = props.getString(DEFAULT_TIMEZONE_ID);
      System.setProperty("user.timezone", timezone);
      TimeZone.setDefault(TimeZone.getTimeZone(timezone));
      DateTimeZone.setDefault(DateTimeZone.forID(timezone));
      logger.info("Setting timezone to " + timezone);
    }

    configureMBeanServer();
    if (props.getBoolean(ServerProperties.IS_METRICS_ENABLED, false)) {
      startWebMetrics();
    }
  }

上面是AzkabanWebServer的构造函数,AzkabanWebServer有如下的管理器:

• userManager
• projectManager
• executorManager
• scheduleManager
• triggerManager

Usermanager

用户管理器,管理当前用户是否存在,获取该用户详细信息,比如所在的组,角色.可以通过它实现当前可以操作、查看哪些project

ProjectManager

工程管理器,管理工程创建、上传、下载、存储project,flow,properties信息.获取工程的所有流,获取流的所有job,解析zip包成flows,job

ExecutorManager

executor管理器,它有两种模式,单机版或集群版.如果单机版,获取executor,获取executor正在执行的flow,向executor提交flow、取消job、提交job等

scheduleManager

调度管理器

triggerManager

触发管理器.