这里不再对开源框架XX-JOB做介绍，单纯介绍部分功能实现原理。本篇记录执行器Executor如何注册到任务管理器Admin。
本系列文章基于V2.1.0版本介绍，附github上架构图。
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然后Admin在根据不同策略获取这些地址。
整体大概流程
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工程目录
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以springboot为例
初始化配置文件XxlJobConfig.java -->创建XxlJobSpringExecutor.java(set 执行器和管理器各种信息) bean -->指定init和destory方法 --> XxlJobSpringExecutor执行start()
//从application.properties文件中读取admin和executor信息，并初始化到XxlJobSpringExecutor类中，指定init和destory方法
@Bean(initMethod = "start", destroyMethod = "destroy")
public XxlJobSpringExecutor xxlJobExecutor() {
logger.info(">>>>>>>>>>> xxl-job config init.");
XxlJobSpringExecutor xxlJobSpringExecutor = new XxlJobSpringExecutor();
//设置admin地址，eg：http://127.0.0.1:8080/xxl-job-admin
xxlJobSpringExecutor.setAdminAddresses(adminAddresses);
//设置执行器名称，eg：xxl-job-executor-sample
xxlJobSpringExecutor.setAppName(appName);
//设置执行器ip和port
xxlJobSpringExecutor.setIp(ip);
xxlJobSpringExecutor.setPort(port);
//设置执行器访问口令
xxlJobSpringExecutor.setAccessToken(accessToken);
//设置日志保存路径
xxlJobSpringExecutor.setLogPath(logPath);
//设置日志保存天数
xxlJobSpringExecutor.setLogRetentionDays(logRetentionDays);
return xxlJobSpringExecutor;
}
接着XxlJobSpringExecutor执行start方法
public class XxlJobSpringExecutor extends XxlJobExecutor implements ApplicationContextAware {
@Override
public void start() throws Exception {
// 初始化执行器上面的任务
initJobHandlerRepository(applicationContext);
// refresh GlueFactory
GlueFactory.refreshInstance(1);
// super start
super.start();
}
接着父类XxlJobExecutor 执行start方法
// ---------------------- start + stop ----------------------
public void start() throws Exception {
//设置日志路径
// init logpath
XxlJobFileAppender.initLogPath(logPath);
//设置admin地址及执行器访问口令
// init invoker, admin-client
initAdminBizList(adminAddresses, accessToken);
//设置日志清理线程参数
// init JobLogFileCleanThread
JobLogFileCleanThread.getInstance().start(logRetentionDays);
//任务执行结果回调线程（包含回调失败后重试机制）
// init TriggerCallbackThread
TriggerCallbackThread.getInstance().start();
// init executor-server
//设置执行器ip和port
port = port>0?port: NetUtil.findAvailablePort(9999);
ip = (ip!=null&&ip.trim().length()>0)?ip: IpUtil.getIp();
//注册执行器
initRpcProvider(ip, port, appName, accessToken);
}
接着看上面的initAdminBizList(adminAddresses, accessToken)方法，这一步是初始化Admin的值，以及初始化执行器访问口令，下面看具体执行逻辑
//初始化各种rpc的各种协议
private void initAdminBizList(String adminAddresses, String accessToken) throws Exception {
serializer = Serializer.SerializeEnum.HESSIAN.getSerializer();
if (adminAddresses!=null && adminAddresses.trim().length()>0) {
for (String address: adminAddresses.trim().split(",")) {
if (address!=null && address.trim().length()>0) {
String addressUrl = address.concat(AdminBiz.MAPPING);
// 这里的getObject() 返回的是一个动态代理对象，代理对象在使用方法时，并不是真实的自己调用，而是委托尤其关联到的hander对象的invoke方法来调用
AdminBiz adminBiz = (AdminBiz) new XxlRpcReferenceBean(
NetEnum.NETTY_HTTP,
serializer,
CallType.SYNC,
LoadBalance.ROUND,
AdminBiz.class,
null,
3000,
addressUrl,
accessToken,
null,
null
).getObject();//getObject方法比较重要
if (adminBizList == null) {
adminBizList = new ArrayList<AdminBiz>();
}
adminBizList.add(adminBiz);
}
}
}
}
public Object getObject() {
//使用动态代理，通过此方法发送请求到Admin的/api接口，api接口收到请求后，解析出具体的方法和参数，获取到对应的Bean，通过反射执行具体的方法，最终实现调用AdminBizImpl.registry()
return Proxy.newProxyInstance(Thread.currentThread()
.getContextClassLoader(), new Class[] { iface },
new InvocationHandler() {
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
接着看initRpcProvider(ip, port, appName, accessToken)方法：
private void initRpcProvider(String ip, int port, String appName, String accessToken) throws Exception {
// init, provider factory
String address = IpUtil.getIpPort(ip, port);
Map<String, String> serviceRegistryParam = new HashMap<String, String>();
serviceRegistryParam.put("appName", appName);
serviceRegistryParam.put("address", address);
xxlRpcProviderFactory = new XxlRpcProviderFactory();
//指定执行器注册类为ExecutorServiceRegistry
xxlRpcProviderFactory.initConfig(NetEnum.NETTY_HTTP, Serializer.SerializeEnum.HESSIAN.getSerializer(), ip, port, accessToken, ExecutorServiceRegistry.class, serviceRegistryParam);
// add services
xxlRpcProviderFactory.addService(ExecutorBiz.class.getName(), null, new ExecutorBizImpl());
//启动执行器注册工厂
// start
xxlRpcProviderFactory.start();
}
接着是 xxlRpcProviderFactory.start()方法
public void start() throws Exception {
// start server
serviceAddress = IpUtil.getIpPort(this.ip, port);
server = netType.serverClass.newInstance();
server.setStartedCallback(new BaseCallback() { // serviceRegistry started
@Override
public void run() throws Exception {
// start registry
if (serviceRegistryClass != null) {
serviceRegistry = serviceRegistryClass.newInstance();
//执行器注册类启动
serviceRegistry.start(serviceRegistryParam);
if (serviceData.size() > 0) {
serviceRegistry.registry(serviceData.keySet(), serviceAddress);
}
}
}
});
server.setStopedCallback(new BaseCallback() { // serviceRegistry stoped
@Override
public void run() {
// stop registry
if (serviceRegistry != null) {
if (serviceData.size() > 0) {
serviceRegistry.remove(serviceData.keySet(), serviceAddress);
}
serviceRegistry.stop();
serviceRegistry = null;
}
}
});
server.start(this);
}
回到ExecutorServiceRegistry的start方法，
public static class ExecutorServiceRegistry extends ServiceRegistry {
@Override
public void start(Map<String, String> param) {
//此处进行注册
// start registry
ExecutorRegistryThread.getInstance().start(param.get("appName"), param.get("address"));
}
@Override
public void stop() {
// stop registry
ExecutorRegistryThread.getInstance().toStop();
}
@Override
public boolean registry(Set<String> keys, String value) {
return false;
}
@Override
public boolean remove(Set<String> keys, String value) {
return false;
}
@Override
public Map<String, TreeSet<String>> discovery(Set<String> keys) {
return null;
}
@Override
public TreeSet<String> discovery(String key) {
return null;
}
}
进入ExecutorRegistryThread.start()方法，
registryThread = new Thread(new Runnable() {
@Override
public void run() {
// registry
while (!toStop) {
try {
RegistryParam registryParam = new RegistryParam(RegistryConfig.RegistType.EXECUTOR.name(), appName, address);
for (AdminBiz adminBiz: XxlJobExecutor.getAdminBizList()) {
try {//此处注册
ReturnT<String> registryResult = adminBiz.registry(registryParam);
if (registryResult!=null && ReturnT.SUCCESS_CODE == registryResult.getCode()) {
registryResult = ReturnT.SUCCESS;
logger.debug(">>>>>>>>>>> xxl-job registry success, registryParam:{}, registryResult:{}", new Object[]{registryParam, registryResult});
break;
} else {
logger.info(">>>>>>>>>>> xxl-job registry fail, registryParam:{}, registryResult:{}", new Object[]{registryParam, registryResult});
}
} catch (Exception e) {
logger.info(">>>>>>>>>>> xxl-job registry error, registryParam:{}", registryParam, e);
}
}
} catch (Exception e) {
if (!toStop) {
logger.error(e.getMessage(), e);
}
}
Admin中接受Executor请求的入口
/**
* Executor调用Admin入口，接受到请求后，在进行反思操作，实现调用具体方法
* Created by xuxueli on 17/5/10.
*/
@Controller
public class JobApiController implements InitializingBean {
@Override
public void afterPropertiesSet() throws Exception {
}
//执行器调用管理器方法入口
@RequestMapping(AdminBiz.MAPPING)
@PermissionLimit(limit=false)
public void api(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
XxlJobScheduler.invokeAdminService(request, response);
}
}
XxlJobScheduler.invokeAdminService(request, response) ->servletServerHandler.handle(null, request, response)->xxlRpcProviderFactory.invokeService(xxlRpcRequest)
public XxlRpcResponse invokeService(XxlRpcRequest xxlRpcRequest) {
// make response
XxlRpcResponse xxlRpcResponse = new XxlRpcResponse();
xxlRpcResponse.setRequestId(xxlRpcRequest.getRequestId());
// match service bean 获取匹配的Bean
String serviceKey = makeServiceKey(xxlRpcRequest.getClassName(), xxlRpcRequest.getVersion());
Object serviceBean = serviceData.get(serviceKey);
// valid
if (serviceBean == null) {
xxlRpcResponse.setErrorMsg("The serviceKey["+ serviceKey +"] not found.");
return xxlRpcResponse;
}
if (System.currentTimeMillis() - xxlRpcRequest.getCreateMillisTime() > 3*60*1000) {
xxlRpcResponse.setErrorMsg("The timestamp difference between admin and executor exceeds the limit.");
return xxlRpcResponse;
}
if (accessToken!=null && accessToken.trim().length()>0 && !accessToken.trim().equals(xxlRpcRequest.getAccessToken())) {
xxlRpcResponse.setErrorMsg("The access token[" + xxlRpcRequest.getAccessToken() + "] is wrong.");
return xxlRpcResponse;
}
try {
// invoke
Class<?> serviceClass = serviceBean.getClass();
String methodName = xxlRpcRequest.getMethodName();
Class<?>[] parameterTypes = xxlRpcRequest.getParameterTypes();
Object[] parameters = xxlRpcRequest.getParameters();
Method method = serviceClass.getMethod(methodName, parameterTypes);
method.setAccessible(true);
//反射调用具体方法
Object result = method.invoke(serviceBean, parameters);
/*FastClass serviceFastClass = FastClass.create(serviceClass);
FastMethod serviceFastMethod = serviceFastClass.getMethod(methodName, parameterTypes);
Object result = serviceFastMethod.invoke(serviceBean, parameters);*/
xxlRpcResponse.setResult(result);
} catch (Throwable t) {
// catch error
logger.error("xxl-rpc provider invokeService error.", t);
xxlRpcResponse.setErrorMsg(ThrowableUtil.toString(t));
}
return xxlRpcResponse;
}
Admin中实现类
@Override
public ReturnT<String> registry(RegistryParam registryParam) {
//注册信息入库
int ret = xxlJobRegistryDao.registryUpdate(registryParam.getRegistGroup(), registryParam.getRegistryKey(), registryParam.getRegistryValue());
if (ret < 1) {
xxlJobRegistryDao.registrySave(registryParam.getRegistGroup(), registryParam.getRegistryKey(), registryParam.getRegistryValue());
// fresh
freshGroupRegistryInfo(registryParam);
}
return ReturnT.SUCCESS;
}
其中Executor动态代理AdminBiz接口和Admin的/api动态反射执行具体方法属于作者自研RPC框架部分，本篇只做了注册部分和解析部分的介绍，后续会单独介绍自研RPC框架部分。
到此，执行器的地址就已经完全注册到管理器中。
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