摘要：續上篇所需技術等說明本編講解一個分布式架構的整個流程，首先對上編中的工程作一些小小的改動，以支持接下來的實驗。本篇中，定義了服務提供者，注冊中心及客戶端消費者三者關系。一服務提供者這里首先對服務端進行改造。
（續上篇）
所需技術：spring、mybatis、druid、flyway、logback、nodejs,zookeeper,dubbo,dubbo-admin等;
說明：本編講解一個分布式架構的整個流程，首先對上編中的demo工程作一些小小的改動，以支持接下來的實驗。特別說明，zookeeper作為服務注冊中心，dubbo-admin作為注冊中心管理客戶端，雖然都是開源軟件，但本章不作安裝部署講解。
目錄結構調整上圖所示，紅框中，作為調整內容，其它內容不變。
簡要
本篇引入了阿里公司開源的分布式服務框架[dubbo][1]。本篇中，定義了provider服務提供者，zookeeper注冊中心及客戶端消費者三者關系。provider是數據源，基于底層的數據交互都在這里完成。provider將服務暴露給zookeeper注冊中心，provider的所有服務都由zookeeper進行統一管理。client作為消費者，連接到注冊中心獲取相應的服務。
本文中消費者部分由nodejs編寫。
一、Provider服務提供者
這里首先對服務端進行改造。提供兩個接口，各一個方法。DemoService接口中提供一個方法，客戶端傳入String型參數，處理此參數后返回客戶端。IUserService接口中提供一個根據id查詢用戶信息的方法。方法實現同上篇文中介紹一樣不變。部分代碼如下：
DemoServiceImpl.java
package com.soyann.provider.demo.impl;
import com.soyann.provider.demo.DemoService;
/**
* @ProjectName: soyann
* @FileName: com.soyann.provider.demo.impl
* @Description: (do what)
* @Copyright: Copyright(C) 2016-2017 All rights Reserved
* @Company: ShenZhen Information Technology Co.,LTD.
* @Author: neil
* @Version V1.0
* @Date: 2017/11/17
*
* Modification History:
* Date Author Version Discription
* -----------------------------------------------------------------------------------
* 2017/11/17 neil 1.0 1.0
* Why & What is modified: <修改原因描述>
*/
public class DemoServiceImpl implements DemoService {
@Override
public String sayHello(String name) {
return "Hello Dubbo,Hello " + name;
}
}
UserServiceImpl.java
package com.soyann.provider.user.service.impl;
import com.soyann.provider.user.mapper.UserMapper;
import com.soyann.provider.user.model.UserEntity;
import com.soyann.provider.user.service.IUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
/**
* @ProjectName: soyann
* @FileName: com.soyann.business.user.service.impl
* @Description: (do what)
* @Copyright: Copyright(C) 2016-2017 All rights Reserved
* @Company: ShenZhen Information Technology Co.,LTD.
* @Author: dell657 neil
* @Version V1.0
* @Date: 2017/10/28
*
* Modification History:
* Date Author Version Discription
* -----------------------------------------------------------------------------------
* 2017/10/28 neil 1.0 1.0
* Why & What is modified: <修改原因描述>
*/
@Service("userService")
public class UserServiceImpl implements IUserService {
@Autowired(required=false)
private UserMapper userMapper;
@Override
public UserEntity getUserById(int userId) {
return userMapper.selectByPrimaryKey(userId);
}
@Override
public List getAllUser() {
return userMapper.getAllUser();
}
}
spring-provider.xml
在spring-applicationContext.xml中，引入spring-provider.xml
添加服務啟動測試類TestProvider.java
package com.soyann.demo;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.io.IOException;
/**
* @ProjectName: soyann
* @FileName: com.soyann.demo
* @Description: (do what)
* @Copyright: Copyright(C) 2016-2017 All rights Reserved
* @Company: ShenZhen Information Technology Co.,LTD.
* @Author: neil
* @Version V1.0
* @Date: 2017/11/17
*
* Modification History:
* Date Author Version Discription
* -----------------------------------------------------------------------------------
* 2017/11/17 neil 1.0 1.0
* Why & What is modified: <修改原因描述>
*/
public class TestProvider {
public static void main(String[] args) throws IOException {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring/spring-applicationContext.xml", "spring/spring-mybatis.xml");
System.out.println(context.getDisplayName() + ": here");
context.start();
System.out.println("服務已經啟動...");
System.in.read();
}
}
運行測試類，輸出以下信息：
……
18:45:48.299 [main] DEBUG ResultSet - {conn-10010, stmt-20003, rs-50003} Header: [installed_rank, version, description, type, script, checksum, installed_on, installed_by, execution_time, success]
18:45:48.299 [main] DEBUG ResultSet - {conn-10010, stmt-20003, rs-50003} closed
18:45:48.299 [main] DEBUG Statement - {conn-10010, stmt-20003} closed
18:45:48.299 [main] INFO DbMigrate - Current version of schema `soyann`: 1.0.1
18:45:48.299 [main] WARN DbMigrate - Schema `soyann` has version 1.0.1, but no migration could be resolved in the configured locations !
18:45:48.300 [main] DEBUG Statement - {conn-10010, pstmt-20004} created. SELECT RELEASE_LOCK("Flyway--294804349")
18:45:48.300 [main] DEBUG Statement - {conn-10010, pstmt-20004} Parameters : []
18:45:48.300 [main] DEBUG Statement - {conn-10010, pstmt-20004} Types : []
18:45:48.300 [main] DEBUG Statement - {conn-10010, pstmt-20004} executed. 0.414796 millis. SELECT RELEASE_LOCK("Flyway--294804349")
18:45:48.300 [main] DEBUG Statement - {conn-10010, pstmt-20004} clearParameters.
18:45:48.300 [main] INFO DbMigrate - Schema `soyann` is up to date. No migration necessary.
18:45:48.301 [main] DEBUG Connection - {conn-10010} setAutoCommit false
18:45:48.301 [main] DEBUG Connection - {conn-10010} commited
18:45:48.301 [main] DEBUG Connection - {conn-10010} setAutoCommit true
18:45:48.302 [main] DEBUG Connection - {conn-10010} pool-recycle
18:45:48.527 [main] DEBUG SqlSessionFactoryBean - Parsed configuration file: "class path resource [mybatis/mybatis-config.xml]"
18:45:48.674 [main] DEBUG SqlSessionFactoryBean - Parsed mapper file: "file [D:workspaceJAVAsoyannprovider argetclassesmybatismappersqlmap-mapping-user.xml]"
org.springframework.context.support.ClassPathXmlApplicationContext@f2a0b8e: here
服務已經啟動...
這樣表示服務已經發布成功！（zookeeper注冊中心要先啟動，啟動方法略）
二、服務消費者部分
消費者部分采用node工程，這里也簡單創建了一個node工程進行連接實驗。目錄結構如下：
這里，必須的文件有三個文件，package.json,server.js,soyannClient-route.js
package.json
{
"name": "nodeClient",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "echo "Error: no test specified" && exit 1",
"build": "babel src -d lib"
},
"keywords": [],
"author": "",
"license": "ISC",
"dependencies": {
"cookie-parser": "^1.4.3",
"express": "^4.16.2",
"http": "^0.0.0",
"js-to-java": "^2.4.0",
"morgan": "^1.9.0",
"node-zookeeper-dubbo": "^2.2.1"
},
"devDependencies": {
"babel-cli": "^6.26.0",
"babel-preset-env": "^1.6.1"
}
}
server.js
/**
* @ProjectName: nodeClient
* @FileName:
* @Description: (服務主入口)
* @Copyright: Copyright(C) 2016-2017 All rights Reserved
* @Company: ShenZhen Information Technology Co.,LTD.
* @Author: dell657 neil
* @Version V1.0
* @Date: 2017/11/17
*
* Modification History:
* Date Author Version Discription
* -----------------------------------------------------------------------------------
* 2017/11/17 neil 1.0 1.0
* Why & What is modified: <修改原因描述>
*/
const logger = require("morgan"),
http = require("http"),
express = require("express"),
bodyParser = require("body-parser"),
debug = require("debug")("mydebug:http"),
cookieParser = require("cookie-parser");
const app = express();
//設置跨域訪問
app.all("*", function (req, res, next) {
if(req.headers.origin == "http://localhost:4200" || req.headers.origin == "http://ng2.com"){
res.header("Access-Control-Allow-Origin",req.headers.origin); //設置跨域訪問
res.header("Access-Control-Allow-Credentials", "true");
res.header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
res.header("Access-Control-Allow-Headers", "Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With, Authorization");
res.header("Content-Type", "application/json");
}
next();
});
app.use(bodyParser.urlencoded({extended: true}));
app.use(bodyParser.json());
app.use(function (err, req, res, next) {
if (err.name === "StatusError") {
res.send(err.status, err.message);
} else {
next(err);
}
});
/*引用模塊*/
app.use(require("./modules/soyannClient-route"));
//app.use(require("./modules/zkclient-route"));
/*監聽端口*/
const port = process.env.PORT || 8090;
http.createServer(app).listen(port, function (err) {
console.log("Node服務已啟動，請訪問：http://localhost:" + port);
});
soyannClient-route.js
/**
* @ProjectName: nodeClient
* @FileName:
* @Description: (do what)
* @Copyright: Copyright(C) 2016-2017 All rights Reserved
* @Company: ShenZhen Information Technology Co.,LTD.
* @Author: dell657 neil
* @Version V1.0
* @Date: 2017/11/17
*
* Modification History:
* Date Author Version Discription
* -----------------------------------------------------------------------------------
* 2017/11/17 neil 1.0 1.0
* Why & What is modified: <修改原因描述>
*/
const express = require("express"),
debug = require("debug")("mydebug:http"),
zookeeperClient = require("node-zookeeper-dubbo");
const app = module.exports = express.Router();
const opt = {
application: {name: "soyann-provider"},
register: "localhost:2181",
dubboVer: "2.5.7",
root: "dubbo",
dependencies: {
Demo: {
interface: "com.soyann.provider.demo.DemoService",
version: "1.0.0",
timeout: 6000,
group: "g-demo",
methodSignature: {
sayHello: sayHello = (name) => (java) => [ java.String(name) ]
}
},
Soyann: {
interface: "com.soyann.provider.user.service.IUserService",
version: "2.0.0",
timeout: 6000,
group: "g-soyann",
methodSignature: {
getUserById: getUserById = (id) => [ {"$class": "int", "$": id} ]
}
}
}
};
opt.java = require("js-to-java");
const Dubbo = new zookeeperClient(opt);
/*傳參數實例*/
app.post("/api/sayHello",(req,res)=>{
debug(req);
Dubbo.Demo
.sayHello(req.body.name)
.then(data=>res.send(data))
.catch(err=>res.send(err))
});
/*傳遞整形參數*/
app.post("/api/getUserById",(req,res)=>{
Dubbo.Soyann
.getUserById(Number(req.body.id))
.then(data=>res.send(data))
.catch(err=>res.send(err))
});
/*訪問實例*/
app.get("/api/demo",(req,res)=>{
const result={"result":"Hello world Neil!"};
debug(result);
res.status(200).send(result);
});
這個工程中，使用了node-zookeeper-dubbo這個開源模塊，使得node與java通信成為現實。
啟動工程，后面不用再說了吧，本篇完結。
http://dubbo.io/
