SpringBoot + nodeJS + zookeeper 搭建微服务示例
总体来说该项目由服务注册 + 服务发现 + 服务代理 + 服务调用四部分组成。
使用java客户的开发服务注册组件，它是整个微服务架构中的服务注册表，使用Node.js客户端开发服务发现组件，它用于在服务注册表中根据具体的服务名称获取对应的服务配置。
由项目1提供接口
/**
* 注册服务信息
* @param serviceName 服务名称
* @param serviceAddress 注册服务的地址
*/
void register(String serviceName,String serviceAddress);由项目2依赖项目1，实现其提供的接口
@Component
public class ServiceRegistryImpl implements ServiceRegistry,Watcher{
private static Logger logger = LoggerFactory.getLogger(ServiceRegistryImpl.class);
private static CountDownLatch latch = new CountDownLatch(1);
private static final int SESSION_TIMEOUT = 5000;
private static final String REGISTRY_PATH = "/registry";
private ZooKeeper zk;
public ServiceRegistryImpl() {
}
/**
*
* @param zkServers registry.servers
*/
public ServiceRegistryImpl(String zkServers) {
try {
zk = new ZooKeeper(zkServers, SESSION_TIMEOUT, this);
latch.await();
logger.info("connected to zookeeper");
logger.info("connected to zookeeper");
} catch (Exception e) {
logger.error("create zookeeper client failure",e);
e.printStackTrace();
}
}
@Override
public void register(String serviceName, String serviceAddress) {
try {
//创建根节点（持久节点）
String registryPath = REGISTRY_PATH;
if(zk.exists(registryPath, false) == null) {
zk.create(registryPath, null, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
logger.info("create registry node:{}",registryPath);
}
//创建服务节点（持久节点）
String servicePath = registryPath + "/" + serviceName;
if(zk.exists(servicePath, false) == null) {
zk.create(servicePath, null, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
logger.info("create service node:{}",servicePath);
}
//创建地址节点（临时顺序节点）
String addressPath = servicePath + "/address-";
if(zk.exists(addressPath, false) == null) {
String addressNode = zk.create(addressPath, serviceAddress.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);
logger.info("create address node:{}",addressNode);
}
} catch (Exception e) {
logger.error("create node failure",e);
e.printStackTrace();
}
}
@Override
public void process(WatchedEvent event) {
if(event.getState() == Event.KeeperState.SyncConnected) {
latch.countDown();
}
}
}项目启动时注册服务
@Component
public class RegistryZooListener implements ServletContextListener {
@Value("${server.address}")
private String serverAddress;
@Value("${server.port}")
private int serverPort;
@Autowired
private ServiceRegistry serviceRegistry;
@Override
public void contextInitialized(ServletContextEvent servletContextEvent) {
ServletContext servletContext = servletContextEvent.getServletContext();
WebApplicationContext applicationContext = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext);
RequestMappingHandlerMapping mapping = applicationContext.getBean(RequestMappingHandlerMapping.class);
//获取到所有的请求mapping
Map<RequestMappingInfo, HandlerMethod> infoMap = mapping.getHandlerMethods();
for (RequestMappingInfo info:infoMap.keySet()){
String serviceName = info.getName();
if (serviceName != null){
//注册服务
// System.out.println(serviceName);
serviceRegistry.register(serviceName, String.format("%s:%d",serverAddress,serverPort));
}
}
}
@Override
public void contextDestroyed(ServletContextEvent servletContextEvent) {
}
}接下来的工作将是服务发现
ar express = require('express');
var zookeeper = require('node-zookeeper-client');
var httpProxy = require('http-proxy');
var PORT = 1234;
var CONNECTION_STRING = '127.0.0.1:2181';
var REGISTER_ROOT = "/registry";
//连接zookeeper
var zk = zookeeper.createClient(CONNECTION_STRING);
zk.connect();
//创建代理服务器对象并监听错误事件
var proxy = httpProxy.createProxyServer();
proxy.on('error', function (err, req, res) {
res.end();//输出空白数据
});
//启动web服务器
var app = express();
app.use(express.static('public'));
app.all('*', function (req, res) {
//处理图标请求
if (req.path == '/favicon.ico') {
res.end();
return;
}
//获取服务器名称
var serviceName = req.get('Service-Name');
console.log('service-name : %s', serviceName);
if (!serviceName) {
console.log('Service-Name request head is not exist');
res.end();
return;
}
//获取服务路径
var servicePath = REGISTER_ROOT + '/' + serviceName;
console.log('service path is : %s', servicePath);
//获取服务路径下的地址节点
zk.getChildren(servicePath, function (error, addressNodes) {
console.log("into zk getChildren!");
if (error) {
console.log(error.stack);
res.end();
return;
}
var size = addressNodes.length;
if (size == 0) {
console.log('address node is not exist');
res.end();
return;
}
//生成地址路径
var addressPath = servicePath + '/';
if (size == 1) {
//如果只有一个地址
addressPath += addressNodes[0];
} else {
//如果存在多个地址,则随即获取一个地址
addressPath += addressNodes[parseInt(Math.random() * size)];
}
console.log('addressPath is : %s',addressPath);
//获取服务地址
zk.getData(addressPath,function (error,serviceAddress) {
if (error) {
console.log(error.stack);
res.end();
return;
}
console.log('serviceAddress is : %s',serviceAddress);
if (!serviceAddress) {
console.log('serviceAddress is not exist');
res.end();
return;
}
console.log('TART###http://' + serviceAddress);
proxy.web(req,res,{
target:'http://'+serviceAddress//目标地址
})
});
});
});
app.listen(PORT,function () {
console.log('server is running at %d',PORT);
});随后调用即可
$.ajax({
method: "GET",
url: 'user/hello',
headers: {
'Service-Name': 'hello'
},
success: function (data) {
console.log("data:" + data);
$("#console").append(data + '<br>');
},
error:function (error){
console.log("error")
}
});