Ele SOA Container

Ele SOA Container设计
我的github pages 地址：https://alexanderwangsgithub.github.io/

Core

Container

public class Container {    private final static Log logger = LogFactory.getLog(Container.class);    public static void main(String[] args) {        try {            CoreBootstrap.getInstance().include((args != null && args.length > 0) ? args : new String[] { CoreConsts.DEFAULT_CONFIG_PATH }).start();        } catch (Throwable t) {            logger.error("Throwable Occurs in Container!", t);            CoreBootstrap.getInstance().stop(-1);        }    }}

即通过CoreBootstrap.getInstance().include(new SOAConf[]{this.soaConfig}).start()来启动，这种方式需要启动时将参数传入main()，需要按照约定。

如果以arena.api.melody为例：

applicationDefaultJvmArgs=["-DAPPID=arena.api.melody",                           "-Dlistener=me.ele.napos.arena.api.melody.impl.ArenaApiMelodyContextListener",                           "-DCONF_PATH=$rootDir/config",                           "-Delog.config=$rootDir/config/elog.xml"]

CoreBootstrap

CoreBootstrap提供了更加灵活的配置方法：

   public CoreBootstrap include(SOAConf... soaConfs) {        if (soaConfs != null) {            for (SOAConf soaConf : soaConfs) {                if (soaConf != null) {                    include(soaConf.getCommonConf());                    include(soaConf.getServerConf());                    include(soaConf.getClientConfs());                }            }        }        return this;    }

只需要将SOAConf实例传入即可。

CoreInitializer

CoreBootstrap.start()通过CoreInitializer.init()启动。

CommonConf完成Huskar、MetricClient的启动和Etrace的URL配置。在RPC的InvokeHandler里会调用Trace，Trace本身完成了一个类似Statsd、Collectd的实现，包括Ejedis、Ejdbc都是通过Trace完成数据发送。

ps：Ejedis通过拼接字节码完成了替换了Jedis本省的几个类。Ejdbc在提交的时候调用Trace记录事件。

 public void commit() throws SQLException {        Transaction t = Trace.newTransaction(Constants.SQL, "commit");        Trace.logEvent(Constants.SQL_DATABASE, dbName);        try {            if (CommentGenerator.isConnToDal(username)) {                setComment(CommentGenerator.genAnnotation());            }            // business logic            conn.commit();            /////            t.setStatus(Constants.SUCCESS);        } catch (SQLException e) {            Trace.logError(e);            t.setStatus(e);            throw e;        } finally {            t.complete();            if (CommentGenerator.isConnToDal(username)) {                setComment(null);// reset            }        }    }

ServerConf完成三个server的启动：

startBizServer：业务的Server

startDaemonServer： 守护server，包括心跳、配置、dump等。

registerService： 服务注册，appspec.yml，即supervisor

Server

业务Server

    private static void startBizServer(ServerConf serverConf) {        ServerProtocol serverProtocol = Enum.valueOf(ServerProtocol.class, serverConf.getProtocol());        if (serverProtocol == null) {            throw new CoreException("Unsupported server protocol(" + serverConf.getProtocol() + ")!");        }        server = serverProtocol.createServer(serverConf);        server.start(serverConf.getPort());    }

安全的单例模式

public enum ServerProtocol {    json {        @Override        public Server<?> createServer(ServerConf serverConf) {            return new JsonServer(serverConf.getName(), serverConf.getGroup(), serverConf.isValidatable(), createTaskExecutor(serverConf),                    createDgStrategy(serverConf), createAuthStrategy(serverConf), serverConf.getInitializer(), serverConf.getInterfaces(),                    serverConf.getWorkerGroupSize());        }        @Override        protected DgStrategy createDgStrategy(ServerConf serverConf) {            return new JsonHuskarDgStrategy(HuskarHandle.get().getMySwitch());        }    };    public abstract Server<?> createServer(ServerConf serverConf);    protected abstract DgStrategy createDgStrategy(ServerConf serverConf);    protected TaskExecutor createTaskExecutor(ServerConf serverConf) {        return new FIFRTaskExecutor(serverConf.getName(), serverConf.getThreadPoolSize(), serverConf.getBufferQueueSize() > 0 ? serverConf.getBufferQueueSize()                : serverConf.getThreadPoolSize());    }    protected AuthStrategy createAuthStrategy(ServerConf serverConf) {        HuskarAuthStrategy huskarAuthStrategy = new HuskarAuthStrategy();        try {            HuskarHandle.get().getConfigHandle().register(new DataIncidentRegistry<>(huskarAuthStrategy, serverConf.getName(), HuskarConsts.CLUSTER_OVERALL));        } catch (HuskarException e) {            throw new CoreException(e);        }        return new MergedAuthStrategy(huskarAuthStrategy,                               serverConf.getInitializer().getAuthStrategy());    }}

RPC

JsonServer

public class JsonServer extends Server<JsonServerBean> {    private final HttpServer httpServer;    public JsonServer(String name, String group, boolean validatable, TaskExecutor taskExecutor, DgStrategy dgStrategy, AuthStrategy authStrategy,            IServiceInitializer initializer, List<Class<?>> ifaces, int workerGroupSize) {        super(name, group, validatable, taskExecutor, dgStrategy, authStrategy, initializer, ifaces, new JsonServerBean(ifaces));        @SuppressWarnings("serial")        List<ChannelHandler> handlerChain = new ArrayList<ChannelHandler>() {            {                add(new JsonResponseSerializer());                add(new HttpServerUrlHandler(new DefaultHandler(HttpResponseStatus.BAD_REQUEST)).register(HttpMethod.POST, JsonConsts.RPC_URI,                        new JsonRequestDeserializer(JsonServer.this)));            }        };        httpServer = new HttpServer(workerGroupSize, (ch) -> handlerChain.forEach((handler) -> ch.pipeline().addLast(handler)));    }    @Override    public void start(int port) {        try {            httpServer.start(port);        } catch (Exception t) {            throw new RpcException("Fail to Start server!", t);        }    }}

通过FIFRTaskExecutor实现异步，类似于Vine1.x里面的异步[AsyncHandle]({% post_url 2016-06-13-Async_queue_program_model %})（这是在Vine实现的RPC）。其实就是利用netty的ServerBootstrap封了一个HttpServer，JsonRequestDeserializer和JsonResponseSerializer作为ChannelHandler。对于这种封了Server再继承实现DefaultServer的作法便于扩展，如果结合了配置中心的话就可以把bossGroup&workerGroup放到配置中心。关于利用netty实现RPC，我打算另起一篇。

rpc通过一种自定义jsonProtocol实现{JsonBasicHeader.class, JsonExceptionSnap.class, JsonProtoHeader, JsonRequest.class, JsonResponse.class}。

每一次调用通过一个JsonTask。

JsonTask

public class JsonTask extends Task<JsonServerBean> {    private final JsonRequest request;    private final ChannelHandlerContext ctx;    @Getter    private final boolean isKeepAlive;    @Getter    private final JsonResponse response;    public JsonTask(Server<JsonServerBean> server, String ifaceName, String methodName, MultiMessageProducer producer, String requestString,            JsonRequest request, ChannelHandlerContext ctx, boolean isKeepAlive) {        super(server, ifaceName, methodName, producer, requestString);        this.request = request;        this.ctx = ctx;        this.isKeepAlive = isKeepAlive;        this.response = new JsonResponse(request.getVer(), request.getReqId());    }    @Override    protected void prepare() {        InterfaceInfo interfaceInfo = server.getBean().getServiceInfo().getInterfaceInfo(request.getIface());        MethodInfo methodInfo = interfaceInfo.getMethodInfo(request.getMethod());        method = methodInfo.getMethod();        args = deserializeArgs(methodInfo);        metas = deserializeMetas(interfaceInfo);    }    private Map<String, Object> deserializeArgs(MethodInfo methodInfo) {        try {            Map<String, Object> args = methodInfo.getDefaultArgs();            Map<String, String> argJsons = request.getArgs();            if (argJsons != null) {                for (Entry<String, String> entry : argJsons.entrySet()) {                    args.put(entry.getKey(), JacksonHelper.getMapper().readValue(entry.getValue(), methodInfo.getParamInfo(entry.getKey()).getJavaType()));                }            }            return args;        } catch (IOException e) {            throw new JacksonException("Fail to Deserialize Args!", e);        }    }    private Map<String, Object> deserializeMetas(InterfaceInfo interfaceInfo) {        try {            Map<String, Object> metas = new HashMap<>();            Map<String, String> metaJsons = request.getMetas();            if (metaJsons != null) {                Map<String, JavaType> metaInfos = interfaceInfo.getMetaInfos();                for (Entry<String, String> entry : metaJsons.entrySet()) {                    String key = entry.getKey();                    JavaType javaType = metaInfos.get(key);                    if (javaType == null) {                        throw new VerificationException("Unknown Meta(" + entry.getKey() + ") Found!");                    }                    metas.put(key, JacksonHelper.getMapper().readValue(entry.getValue(), javaType));                }            }            return metas;        } catch (IOException e) {            throw new JacksonException("Fail to Deserialize Metas!", e);        }    }    @Override    protected void handleResult(Object result) {        response.setOriginResult(result);        ctx.writeAndFlush(this);    }    @Override    protected void handleThrowable(Throwable t) {        response.setOriginEx(t);        ctx.writeAndFlush(this);    }    @Override    protected String getClientIpAddress() {        SocketAddress socketAddress = ctx.channel().remoteAddress();        if (socketAddress instanceof InetSocketAddress) {            return ((InetSocketAddress) socketAddress).getAddress().getHostAddress();        } else {            return null;        }    }}

可以比对[AsyncInvoke接口设计]({% post_url 2016-06-13-Async_queue_program_model %})，预处理、处理、返回结果、异常处理、exit。

未完。。。