refactor zkClient; update documents (#683)

* update english documents

* refactor zk client

* update documents

* update zkclient

docs/en_us/Backend Deployment Document.md → docs/en_US/Backend Deployment Document.md

@@ -42,20 +42,13 @@ escheduler  ALL=(ALL)       NOPASSWD: NOPASSWD: ALL
 #### Preparations 3: SSH Secret-Free Configuration
 Configure SSH secret-free login on deployment machines and other installation machines. If you want to install easyscheduler on deployment machines, you need to configure native password-free login itself.
 
-
-
 - [Connect the host and other machines SSH](http://geek.analysys.cn/topic/113)
 
-
 #### Preparations 4: database initialization
 
 * Create databases and accounts
 
-    Enter the mysql command line service by following MySQL commands:
-
-    > mysql -h {host} -u {user} -p{password} 
-
-    Then execute the following command to create database and account
+    Execute the following command to create database and account
     
     ```sql 
     CREATE DATABASE escheduler DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_general_ci;
@@ -64,17 +57,8 @@ Configure SSH secret-free login on deployment machines and other installation ma
     flush privileges;
     ```
 
-* Versions 1.0.0 and 1.0.1 create tables and import basic data
-    Instructions：在escheduler-backend/sql/escheduler.sql和quartz.sql
-
-    ```sql
-    mysql -h {host} -u {user} -p{password} -D {db} < escheduler.sql
-    
-    mysql -h {host} -u {user} -p{password} -D {db} < quartz.sql
-    ```
-
-* Version 1.0.2 later (including 1.0.2) creates tables and imports basic data
-    Modify the following attributes in conf/dao/data_source.properties
+* creates tables and imports basic data
+    Modify the following attributes in ./conf/dao/data_source.properties
 
     ```
         spring.datasource.url
@@ -88,7 +72,7 @@ Configure SSH secret-free login on deployment machines and other installation ma
 
 #### Preparations 5: Modify the deployment directory permissions and operation parameters
 
-Let's first get a general idea of the role of files (folders) in the escheduler-backend directory after decompression.
+     instruction of escheduler-backend directory 
 
 ```directory
 bin : Basic service startup script
@@ -99,7 +83,7 @@ sql : The project relies on SQL files
 install.sh :  One-click deployment script
 ```
 
-- Modify permissions (please modify the deployUser to the corresponding deployment user) so that the deployment user has operational privileges on the escheduler-backend directory
+- Modify permissions (please modify the 'deployUser' to the corresponding deployment user) so that the deployment user has operational privileges on the escheduler-backend directory
 
     `sudo chown -R deployUser:deployUser escheduler-backend`
 
@@ -109,9 +93,9 @@ install.sh :  One-click deployment script
 
  - Modify the parameters in **install.sh** to replace the values required by your business
    - MonitorServerState switch variable, added in version 1.0.3, controls whether to start the self-start script (monitor master, worker status, if off-line will start automatically). The default value of "false" means that the self-start script is not started, and if it needs to start, it is changed to "true".
-   - hdfsStartupSate switch variable controls whether to starthdfs
+   - 'hdfsStartupSate' switch variable controls whether to start hdfs
       The default value of "false" means not to start hdfs
-      If you need to start hdfs instead of "true", you need to create the hdfs root path by yourself, that is, hdfsPath in install.sh.
+      Change the variable to 'true' if you want to use hdfs, you also need to create the hdfs root path by yourself, that 'hdfsPath' in install.sh.
 
  - If you use hdfs-related functions, you need to copy**hdfs-site.xml** and **core-site.xml** to the conf directory
 
@@ -129,7 +113,7 @@ Automated deployment is recommended, and experienced partners can use source dep
 
     `sh install.sh` 
 
-- Use the jps command to see if the service is started (jps comes with Java JDK)
+- Use the `jps` command to check if the services are started (`jps` comes from `Java JDK`)
 
 ```aidl
     MasterServer         ----- Master Service
@@ -138,7 +122,8 @@ Automated deployment is recommended, and experienced partners can use source dep
     ApiApplicationServer ----- API Service
     AlertServer          ----- Alert Service
 ```
-If there are more than five services, the automatic deployment is successful
+
+If all services are normal, the automatic deployment is successful
 
 
 After successful deployment, the log can be viewed and stored in a specified folder.
@@ -164,49 +149,46 @@ After downloading the release version of the source package, unzip it into the r
 
 * View directory
 
-After normal compilation, target/escheduler-{version}/ is generated in the current directory
-
-
-
+After normal compilation, ./target/escheduler-{version}/ is generated in the current directory
 
 
 ### 2.3  Start-and-stop services commonly used in systems (for service purposes, please refer to System Architecture Design for details)
 
-* stop all services in the cluster at one click
+* stop all services in the cluster
   
    ` sh ./bin/stop_all.sh`
    
-* one click to open all services in the cluster
+* start all services in the cluster
   
    ` sh ./bin/start_all.sh`
 
-* start and stop Master
+* start and stop one master server
 
 ```start master
 sh ./bin/escheduler-daemon.sh start master-server
 sh ./bin/escheduler-daemon.sh stop master-server
 ```
 
-* start and stop Worker
+* start and stop one worker server
 
 ```start worker
 sh ./bin/escheduler-daemon.sh start worker-server
 sh ./bin/escheduler-daemon.sh stop worker-server
 ```
 
-* start and stop Api
+* start and stop api server
 
 ```start Api
 sh ./bin/escheduler-daemon.sh start api-server
 sh ./bin/escheduler-daemon.sh stop api-server
 ```
-* start and stop Logger
+* start and stop logger server
 
 ```start Logger
 sh ./bin/escheduler-daemon.sh start logger-server
 sh ./bin/escheduler-daemon.sh stop logger-server
 ```
-* start and stop Alert
+* start and stop alert server
 
 ```start Alert
 sh ./bin/escheduler-daemon.sh start alert-server
@@ -214,7 +196,7 @@ sh ./bin/escheduler-daemon.sh stop alert-server
 ```
 
 ## 3、Database Upgrade
-Database upgrade is a function added in version 1.0.2. The database can be upgraded automatically by executing the following commands
+Database upgrade is a function added in version 1.0.2. The database can be upgraded automatically by executing the following command:
 
 ```upgrade
 sh ./script/upgrade_escheduler.sh

docs/en_us/Backend development documentation.md → docs/en_US/Backend development documentation.md

@@ -8,7 +8,7 @@
  * [Maven](http://maven.apache.org/download.cgi)(3.3+) ：Must be installed
 
 Because the escheduler-rpc module in EasyScheduler uses Grpc, you need to use Maven to compile the generated classes.
-For those who are not familiar with Maven, please refer to: [maven in five minutes](http://maven.apache.org/guides/getting-started/maven-in-five-minutes.html)(3.3+)
+For those who are not familiar with maven, please refer to: [maven in five minutes](http://maven.apache.org/guides/getting-started/maven-in-five-minutes.html)(3.3+)
 
 http://maven.apache.org/install.html
 
@@ -23,7 +23,7 @@ After importing the EasyScheduler source code into the development tools such as
 
 * View directory
 
-After normal compilation, it will generate target/escheduler-{version}/ in the current directory.
+After normal compilation, it will generate ./target/escheduler-{version}/ in the current directory.
 
 ```
     bin

docs/en_us/Frontend Deployment Document.md → docs/en_US/Frontend Deployment Document.md

@@ -31,7 +31,7 @@ esc_proxy="8888"
 esc_proxy_port="http://192.168.xx.xx:12345"
 ```
 
->Front-end automatic deployment based on Linux system`yum`operation, before deployment, please install and update`yum`
+>Front-end automatic deployment based on Linux system `yum` operation, before deployment, please install and update`yum`
 
 under this directory, execute`./install-escheduler-ui.sh` 
 

docs/en_us/System manual.md → docs/en_US/System manual.md

@@ -7,9 +7,6 @@
 
 ## Operational Guidelines
 
-  - Administrator accounts can only be managed in terms of authority, do not participate in specific business, can not create projects, and can not perform related operations on process definition.
-  - The following operations can only be performed by using ordinary user login system.
-
 ### Create a project
 
   - Click "Project - > Create Project", enter project name,  description, and click "Submit" to create a new project.
@@ -18,7 +15,7 @@
       <img src="https://user-images.githubusercontent.com/53217792/61776719-2ee50380-ae2e-11e9-9d11-41de8907efb5.png" width="60%" />
  </p>
 
-> Project Home Page contains task status statistics, process status statistics, process definition statistics, queue statistics, command statistics.
+> Project Home Page contains task status statistics, process status statistics.
 
  - Task State Statistics: It refers to the statistics of the number of tasks to be run, failed, running, completed and succeeded in a given time frame.
  - Process State Statistics: It refers to the statistics of the number of waiting, failing, running, completing and succeeding process instances in a specified time range.

docs/en_us/Upgrade documentation.md → docs/en_US/Upgrade documentation.md

 
 # EasyScheduler upgrade documentation
 
-## 1. Back up the previous version of the file and database
+## 1. Back up the previous version of the files and database
 
 ## 2. Stop all services of escheduler
 
@@ -9,7 +9,7 @@
 
 ## 3. Download the new version of the installation package
 
-- [gitee](https://gitee.com/easyscheduler/EasyScheduler/attach_files), download the latest version of the front and rear installation package (backend referred to as escheduler-backend, front end referred to as escheduler-ui)
+- [gitee](https://gitee.com/easyscheduler/EasyScheduler/attach_files), download the latest version of the front and back installation packages (backend referred to as escheduler-backend, front end referred to as escheduler-ui)
 - The following upgrade operations need to be performed in the new version of the directory
 
 ## 4. Database upgrade
@@ -27,11 +27,12 @@
 
 ## 5. Backend service upgrade
 
-- Modify the contents of the install.sh configuration and execute the upgrade script
+- Modify the content of the install.sh configuration and execute the upgrade script
   
   `sh install.sh`
 
 ## 6. Frontend service upgrade
+
 - Overwrite the previous version of the dist directory
 - Restart the nginx service
   

docs/zh_CN/前端开发文档.md

@@ -106,7 +106,7 @@ npm install node-sass --unsafe-perm //单独安装node-sass依赖
 
 `src => combo` 项目第三方资源本地化 `npm run combo`具体查看`build/combo.js`
 
-`src => font` 字体图标库可访问 https://www.iconfont.cn 进行添加 注意：字体库用的自己的 二次开发需要重新引入自己的库 `src/sass/common/_font.scss`
+`src => font` 字体图标库可访问 `https://www.iconfont.cn` 进行添加 注意：字体库用的自己的 二次开发需要重新引入自己的库 `src/sass/common/_font.scss`
 
 `src => images` 公共图片存放
 

docs/zh_CN/后端开发文档.md

@@ -8,12 +8,12 @@
  * [Maven](http://maven.apache.org/download.cgi)(3.3+) ：必装 
 
 因EasyScheduler中escheduler-rpc模块使用到Grpc，需要用到Maven编译生成所需要的类
-对Maven不熟的伙伴请参考: [maven in five minutes](http://maven.apache.org/guides/getting-started/maven-in-five-minutes.html)(3.3+)
+对maven不熟的伙伴请参考: [maven in five minutes](http://maven.apache.org/guides/getting-started/maven-in-five-minutes.html)(3.3+)
 
 http://maven.apache.org/install.html
 
 ## 项目编译
-将EasyScheduler源码下载导入Idea等开发工具后，首先转为Maven项目(右键点击后选择"Add Framework Support")
+将EasyScheduler源码下载导入Idea开发工具后，首先转为Maven项目(右键点击后选择"Add Framework Support")
 
 * 执行编译命令：
 
@@ -23,7 +23,7 @@ http://maven.apache.org/install.html
 
 * 查看目录
 
-正常编译完后，会在当前目录生成 target/escheduler-{version}/
+正常编译完后，会在当前目录生成 ./target/escheduler-{version}/
 
 ```
     bin

docs/zh_CN/后端部署文档.md

@@ -43,12 +43,8 @@ escheduler  ALL=(ALL)       NOPASSWD: NOPASSWD: ALL
 #### 准备四：数据库初始化
 
 * 创建database和账号
-
-    通过以下mysql命令进入mysql命令行服务：
-
-    > mysql -h {host} -u {user} -p{password} 
-
-    然后执行以下命令创建database和账号
+    
+    执行以下命令创建database和账号
     
     ```sql 
     CREATE DATABASE escheduler DEFAULT CHARACTER SET utf8 DEFAULT COLLATE utf8_general_ci;
@@ -57,17 +53,8 @@ escheduler  ALL=(ALL)       NOPASSWD: NOPASSWD: ALL
     flush privileges;
     ```
 
-* 1.0.0和1.0.1版本创建表和导入基础数据
-    说明：在escheduler-backend/sql/escheduler.sql和quartz.sql
-
-    ```sql
-    mysql -h {host} -u {user} -p{password} -D {db} < escheduler.sql
-    
-    mysql -h {host} -u {user} -p{password} -D {db} < quartz.sql
-    ```
-
-* 1.0.2之后(含1.0.2)版本创建表和导入基础数据
-    修改conf/dao/data_source.properties中的下列属性
+* 创建表和导入基础数据
+    修改./conf/dao/data_source.properties中的下列属性
 
     ```
         spring.datasource.url
@@ -81,7 +68,7 @@ escheduler  ALL=(ALL)       NOPASSWD: NOPASSWD: ALL
 
 #### 准备五: 修改部署目录权限及运行参数
 
-我们先来大体了解下解压后escheduler-backend目录下的文件(夹)的作用
+    escheduler-backend目录介绍
 
 ```
 bin : 基础服务启动脚本
@@ -92,7 +79,7 @@ sql : 项目依赖sql文件
 install.sh : 一键部署脚本
 ```
 
-- 修改权限(请将deployUser自行修改为对应部署用户)，使得部署用户对escheduler-backend目录有操作权限
+- 修改权限(请将'deployUser'字段修改为对应部署用户)，使得部署用户对escheduler-backend目录有操作权限
     
     `sudo chown -R deployUser:deployUser escheduler-backend`
 
@@ -124,7 +111,7 @@ install.sh : 一键部署脚本
 
     `sh install.sh` 
 
-- 使用jps命令查看服务是否启动(jps为java JDK自带)
+- 使用`jps`命令查看服务是否启动(`jps`为`java JDK`自带)
 
 ```aidl
     MasterServer         ----- master服务
@@ -133,7 +120,7 @@ install.sh : 一键部署脚本
     ApiApplicationServer ----- api服务
     AlertServer          ----- alert服务
 ```
-如果有以上5个服务，说明自动部署成功
+如果以上服务都正常启动，说明自动部署成功
 
 
 部署成功后，可以进行日志查看，日志统一存放于指定文件夹内
@@ -159,7 +146,7 @@ install.sh : 一键部署脚本
 
 * 查看目录
 
-正常编译完后，会在当前目录生成 `target/escheduler-{version}/`
+正常编译完后，会在当前目录生成 `./target/escheduler-{version}/`
 
 ```查看目录
  ../

docs/zh_CN/系统使用手册.md

@@ -7,9 +7,6 @@
 
 ## 操作指南
 
-  - 管理员账号只能在权限上进行管理，不参与具体的业务，不能创建项目，不能对流程定义执行相关操作
-  - 以下操作需要使用普通用户登录系统才能进行。
-
 ### 创建项目
 
   - 点击“项目管理->创建项目”，输入项目名称，项目描述，点击“提交”，创建新的项目。

escheduler-common/src/main/java/cn/escheduler/common/zk/AbstractZKClient.java

@@ -64,16 +64,6 @@ public abstract class AbstractZKClient {
 	 */
 	protected String deadServerZNodeParentPath = null;
 
-	/**
-	 *  master node parent path
-	 */
-	protected String masterZNodeParentPath = null;
-
-	/**
-	 *  worker node parent path
-	 */
-	protected String workerZNodeParentPath = null;
-
 	/**
 	 * server stop or not
 	 */
@@ -318,18 +308,16 @@ public abstract class AbstractZKClient {
 		List<String> childrenList = new ArrayList<>();
 		try {
 			// read master node parent path from conf
-			masterZNodeParentPath = conf.getString(Constants.ZOOKEEPER_ESCHEDULER_MASTERS);
-			if(zkClient.checkExists().forPath(masterZNodeParentPath) != null){
-				childrenList = zkClient.getChildren().forPath(masterZNodeParentPath);
+			if(zkClient.checkExists().forPath(getZNodeParentPath(ZKNodeType.MASTER)) != null){
+				childrenList = zkClient.getChildren().forPath(getZNodeParentPath(ZKNodeType.MASTER));
 			}
 		} catch (Exception e) {
 			if(!e.getMessage().contains("java.lang.IllegalStateException: instance must be started")){
 				logger.warn(e.getMessage(),e);
 			}
-
+		}finally {
 			return childrenList.size();
 		}
-		return childrenList.size();
 	}
 
 	/**
@@ -585,9 +573,9 @@ public abstract class AbstractZKClient {
 	public String toString() {
 		return "AbstractZKClient{" +
 				"zkClient=" + zkClient +
-				", deadServerZNodeParentPath='" + deadServerZNodeParentPath + '\'' +
-				", masterZNodeParentPath='" + masterZNodeParentPath + '\'' +
-				", workerZNodeParentPath='" + workerZNodeParentPath + '\'' +
+				", deadServerZNodeParentPath='" + getZNodeParentPath(ZKNodeType.DEAD_SERVER) + '\'' +
+				", masterZNodeParentPath='" + getZNodeParentPath(ZKNodeType.MASTER) + '\'' +
+				", workerZNodeParentPath='" + getZNodeParentPath(ZKNodeType.WORKER) + '\'' +
 				", stoppable=" + stoppable +
 				'}';
 	}

escheduler-server/src/main/java/cn/escheduler/server/zk/ZKMasterClient.java

@@ -182,7 +182,8 @@ public class ZKMasterClient extends AbstractZKClient {
 	 *  monitor master
 	 */
 	public void listenerMaster(){
-		PathChildrenCache masterPc = new PathChildrenCache(zkClient, masterZNodeParentPath, true ,defaultThreadFactory);
+		PathChildrenCache masterPc = new PathChildrenCache(zkClient,
+				getZNodeParentPath(ZKNodeType.MASTER), true ,defaultThreadFactory);
 
 		try {
 			masterPc.start();
@@ -280,7 +281,8 @@ public class ZKMasterClient extends AbstractZKClient {
 	 */
 	public void listenerWorker(){
 
-		PathChildrenCache workerPc = new PathChildrenCache(zkClient,workerZNodeParentPath,true ,defaultThreadFactory);
+		PathChildrenCache workerPc = new PathChildrenCache(zkClient,
+				getZNodeParentPath(ZKNodeType.WORKER),true ,defaultThreadFactory);
 		try {
 			workerPc.start();
 			workerPc.getListenable().addListener(new PathChildrenCacheListener() {

escheduler-server/src/main/java/cn/escheduler/server/zk/ZKWorkerClient.java

@@ -117,7 +117,7 @@ public class ZKWorkerClient extends AbstractZKClient {
 
 		String heartbeatZKInfo = ResInfo.getHeartBeatInfo(new Date());
 
-		workerZNode = workerZNodeParentPath + "/" + OSUtils.getHost() + "_";
+		workerZNode = getZNodeParentPath(ZKNodeType.WORKER) + "/" + OSUtils.getHost() + "_";
 
 		workerZNode = zkClient.create().withMode(CreateMode.EPHEMERAL_SEQUENTIAL).forPath(workerZNode,
 				heartbeatZKInfo.getBytes());
@@ -144,7 +144,7 @@ public class ZKWorkerClient extends AbstractZKClient {
 	 *  monitor worker
 	 */
 	private void listenerWorker(){
-		PathChildrenCache workerPc = new PathChildrenCache(zkClient, workerZNodeParentPath, true, defaultThreadFactory);
+		PathChildrenCache workerPc = new PathChildrenCache(zkClient, getZNodeParentPath(ZKNodeType.WORKER), true, defaultThreadFactory);
 		try {
 
 			Date now = new Date();