关于handler:Consumer最后一个发送请求HandlerTransportClientHandler分析

发送申请

Consumer 的Handler解决链最初一个是TransportClientHandler，这个Handler次要是:

1.发动连贯
2.申请之前执行HttpClientFilter的beforeSendRequest
3.塞入ServiceComb的微服务调用上下文，设置响应回调解决，发送申请

ServiceComb发送申请应用vertx，而vertx网络发送接管构建在netty之上，因此可能异步高并发。

java很大一个特点是向建设大楼的脚手架，一个套在一个下面，举例，serviceComb网络发送与接管是:最根底是jdk，下面是netty，而后是vertx，而后是serviceComb。

1.发动连贯

transport实际上是VertxRestTransport，最终到RestClientInvocation的invoke，这个invoke重点剖析，

public void invoke(Invocation invocation, AsyncResponse asyncResp) throws Exception {
...
    Future<HttpClientRequest> requestFuture = createRequest(ipPort, path);
...
}


  Future<HttpClientRequest> createRequest(IpPort ipPort, String path) {
...
    return httpClientWithContext.getHttpClient().request(requestOptions);
...
  }


    public Future<HttpClientRequest> request(RequestOptions options) {
        ContextInternal ctx = this.vertx.getOrCreateContext();
        PromiseInternal<HttpClientRequest> promise = ctx.promise();
        this.doRequest(options, promise);
        return promise.future();
    }


private void doRequest(HttpMethod method, SocketAddress peerAddress, SocketAddress server, String host, int port, Boolean useSSL, String requestURI, MultiMap headers, long timeout, Boolean followRedirects, ProxyOptions proxyOptions, PromiseInternal<HttpClientRequest> requestPromise) {
...
        this.httpCM.getConnection(eventLoopContext, key, timeout, (ar1) -> {
...

                        requestPromise.tryComplete(req);
...
}
...
}

httpCM 建设连贯胜利后，把requestPromise设置Complete，到此连贯建设实现。