1、okhttp源码解析-整体流程
2、okhttp源码解析-拦截器RetryAndFllowUpInterceptor
3、okhttp源码解析-拦截器BridgeInterceptor
4、okhttp源码解析-拦截器CacheInterceptor
5、okhttp源码解析-拦截器ConnectInterceptor
6、okhttp源码解析-拦截器CallServerInterceptor
7、okhttp源码解析-Dispatcher任务管理器
ConnectInterceptor
这个拦截器主要用于建立tcp连接、http连接、ssl/tls连接。
1.示例图
s'd'f (4).png
2.代码块
- 1.1 ConnectionInterceptor主方法
@Override public Response intercept(Interceptor.Chain chain) throws IOException {
RealInterceptorChain realChain = (RealInterceptorChain) chain;
Request request = realChain.request();
//获取-连接流分配类-对象
StreamAllocation streamAllocation = realChain.streamAllocation();
// We need the network to satisfy this request. Possibly for validating a conditional GET.
boolean doExtensiveHealthChecks = !request.method().equals("GET");
//1.创建RealConnection对象，2.生成HttpStream对象
HttpCodec httpCodec = streamAllocation.newStream(client, chain, doExtensiveHealthChecks);
//这个就是个简单的暴露RealConnection的方法，方便向下一个interceptor传递
RealConnection connection = streamAllocation.connection();
return realChain.proceed(request, streamAllocation, httpStream, connection);
}
- 2.1 StreamAllocation # newStream()方法
public HttpCodec newStream(OkHttpClient client, Interceptor.Chain chain, boolean doExtensiveHealthChecks) {
RealConnection resultConnection = findHealthyConnection(connectTimeout, readTimeout,
writeTimeout, connectionRetryEnabled, doExtensiveHealthChecks);
HttpCodec resultCodec = resultConnection.newCodec(client, chain, this);
synchronized (connectionPool) {
codec = resultCodec;
return resultCodec;
}
}
- 2.2 StreamAllocation # findHealthyConnection()方法
创建一个连接
private RealConnection findHealthyConnection(int connectTimeout, int readTimeout,
int writeTimeout, boolean connectionRetryEnabled, boolean doExtensiveHealthChecks)
throws IOException {
while (true) {
RealConnection candidate = findConnection(connectTimeout, readTimeout, writeTimeout,
connectionRetryEnabled);
return candidate;
}
}
- 2.3 StreamAllocation # findConnection()方法
创建一个连接，调用RealConnection.connect()方法
private RealConnection findConnection(int connectTimeout, int readTimeout, int writeTimeout,
boolean connectionRetryEnabled) throws IOException {
result = new RealConnection(connectionPool, selectedRoute);
// Do TCP + TLS handshakes. This is a blocking operation.
result.connect(
connectTimeout, readTimeout, writeTimeout, connectionRetryEnabled, call, eventListener);
routeDatabase().connected(result.route());
return result;
}
- 3.1 RealConnection # connect()方法
并进行TCP socket连接、TLS 握手、创建Http连接
public void connect(int connectTimeout, int readTimeout, int writeTimeout,
boolean connectionRetryEnabled, Call call, EventListener eventListener) {
if (protocol != null) throw new IllegalStateException("already connected");
RouteException routeException = null;
List<ConnectionSpec> connectionSpecs = route.address().connectionSpecs();
ConnectionSpecSelector connectionSpecSelector = new ConnectionSpecSelector(connectionSpecs);
while (true) {
try {
if (route.requiresTunnel()) {
connectTunnel(connectTimeout, readTimeout, writeTimeout, call, eventListener);
if (rawSocket == null) {
// We were unable to connect the tunnel but properly closed down our resources.
break;
}
} else {
//创建tcp 连接的socket
connectSocket(connectTimeout, readTimeout, call, eventListener);
}
establishProtocol(connectionSpecSelector, call, eventListener);
eventListener.connectEnd(call, route.socketAddress(), route.proxy(), protocol);
break;
} catch (IOException e) {
}
}
}
- 3.2 RealConnection # connectSocket()方法
创建Tcp连接
/** Does all the work necessary to build a full HTTP or HTTPS connection on a raw socket. */
private void connectSocket(int connectTimeout, int readTimeout, Call call,
EventListener eventListener) throws IOException {
Proxy proxy = route.proxy();
Address address = route.address();
rawSocket = proxy.type() == Proxy.Type.DIRECT || proxy.type() == Proxy.Type.HTTP
? address.socketFactory().createSocket()
: new Socket(proxy);
eventListener.connectStart(call, route.socketAddress(), proxy);
rawSocket.setSoTimeout(readTimeout);
Platform.get().connectSocket(rawSocket, route.socketAddress(), connectTimeout);
source = Okio.buffer(Okio.source(rawSocket));
sink = Okio.buffer(Okio.sink(rawSocket));
}
- 3.3 RealConnection # establishProtocol()方法
private void establishProtocol(ConnectionSpecSelector connectionSpecSelector, Call call,
EventListener eventListener) throws IOException {
if (route.address().sslSocketFactory() == null) {
protocol = Protocol.HTTP_1_1;
socket = rawSocket;
return;
}
eventListener.secureConnectStart(call);
connectTls(connectionSpecSelector);
eventListener.secureConnectEnd(call, handshake);
if (protocol == Protocol.HTTP_2) {
socket.setSoTimeout(0); // HTTP/2 connection timeouts are set per-stream.
http2Connection = new Http2Connection.Builder(true)
.socket(socket, route.address().url().host(), source, sink)
.listener(this)
.build();
http2Connection.start();
}
}
- 3.4 RealConnection # connectTls()方法
创建TLS 握手
private void connectTls(ConnectionSpecSelector connectionSpecSelector) throws IOException {
Address address = route.address();
SSLSocketFactory sslSocketFactory = address.sslSocketFactory();
boolean success = false;
SSLSocket sslSocket = null;
try {
// Create the wrapper over the connected socket.
sslSocket = (SSLSocket) sslSocketFactory.createSocket(
rawSocket, address.url().host(), address.url().port(), true /* autoClose */);
// Configure the socket's ciphers, TLS versions, and extensions.
ConnectionSpec connectionSpec = connectionSpecSelector.configureSecureSocket(sslSocket);
if (connectionSpec.supportsTlsExtensions()) {
Platform.get().configureTlsExtensions(
sslSocket, address.url().host(), address.protocols());
}
// Force handshake. This can throw!
sslSocket.startHandshake();
Handshake unverifiedHandshake = Handshake.get(sslSocket.getSession());
// Verify that the socket's certificates are acceptable for the target host.
if (!address.hostnameVerifier().verify(address.url().host(), sslSocket.getSession())) {
X509Certificate cert = (X509Certificate) unverifiedHandshake.peerCertificates().get(0);
throw new SSLPeerUnverifiedException("Hostname " + address.url().host() + " not verified:"
+ "\n certificate: " + CertificatePinner.pin(cert)
+ "\n DN: " + cert.getSubjectDN().getName()
+ "\n subjectAltNames: " + OkHostnameVerifier.allSubjectAltNames(cert));
}
// Check that the certificate pinner is satisfied by the certificates presented.
address.certificatePinner().check(address.url().host(),
unverifiedHandshake.peerCertificates());
// Success! Save the handshake and the ALPN protocol.
String maybeProtocol = connectionSpec.supportsTlsExtensions()
? Platform.get().getSelectedProtocol(sslSocket)
: null;
socket = sslSocket;
source = Okio.buffer(Okio.source(socket));
sink = Okio.buffer(Okio.sink(socket));
handshake = unverifiedHandshake;
protocol = maybeProtocol != null
? Protocol.get(maybeProtocol)
: Protocol.HTTP_1_1;
success = true;
} catch (AssertionError e) {
if (Util.isAndroidGetsocknameError(e)) throw new IOException(e);
throw e;
} finally {
if (sslSocket != null) {
Platform.get().afterHandshake(sslSocket);
}
if (!success) {
closeQuietly(sslSocket);
}
}
}
