/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.squareup.okhttp.internal.http;
import com.squareup.okhttp.Connection;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.internal.Platform;
import com.squareup.okhttp.internal.Util;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpRetryException;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.ProtocolException;
import java.net.Proxy;
import java.net.SocketPermission;
import java.net.URL;
import java.security.Permission;
import java.security.cert.CertificateException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import javax.net.ssl.SSLHandshakeException;
import static com.squareup.okhttp.internal.Util.getEffectivePort;
/**
* This implementation uses HttpEngine to send requests and receive responses.
* This class may use multiple HttpEngines to follow redirects, authentication
* retries, etc. to retrieve the final response body.
*
* <h3>What does 'connected' mean?</h3>
* This class inherits a {@code connected} field from the superclass. That field
* is <strong>not</strong> used to indicate not whether this URLConnection is
* currently connected. Instead, it indicates whether a connection has ever been
* attempted. Once a connection has been attempted, certain properties (request
* header fields, request method, etc.) are immutable. Test the {@code
* connection} field on this class for null/non-null to determine of an instance
* is currently connected to a server.
*/
public class HttpURLConnectionImpl extends HttpURLConnection implements Policy {
/** Numeric status code, 307: Temporary Redirect. */
public static final int HTTP_TEMP_REDIRECT = 307;
/**
* How many redirects should we follow? Chrome follows 21; Firefox, curl,
* and wget follow 20; Safari follows 16; and HTTP/1.0 recommends 5.
*/
private static final int MAX_REDIRECTS = 20;
final OkHttpClient client;
private final RawHeaders rawRequestHeaders = new RawHeaders();
/** Like the superclass field of the same name, but a long and available on all platforms. */
private long fixedContentLength = -1;
private int redirectionCount;
protected IOException httpEngineFailure;
protected HttpEngine httpEngine;
private Proxy selectedProxy;
public HttpURLConnectionImpl(URL url, OkHttpClient client) {
super(url);
this.client = client;
}
@Override public final void connect() throws IOException {
initHttpEngine();
boolean success;
do {
success = execute(false);
} while (!success);
}
@Override public final void disconnect() {
// Calling disconnect() before a connection exists should have no effect.
if (httpEngine != null) {
// We close the response body here instead of in
// HttpEngine.release because that is called when input
// has been completely read from the underlying socket.
// However the response body can be a GZIPInputStream that
// still has unread data.
if (httpEngine.hasResponse()) {
Util.closeQuietly(httpEngine.getResponseBody());
}
httpEngine.release(true);
}
}
/**
* Returns an input stream from the server in the case of error such as the
* requested file (txt, htm, html) is not found on the remote server.
*/
@Override public final InputStream getErrorStream() {
try {
HttpEngine response = getResponse();
if (response.hasResponseBody() && response.getResponseCode() >= HTTP_BAD_REQUEST) {
return response.getResponseBody();
}
return null;
} catch (IOException e) {
return null;
}
}
/**
* Returns the value of the field at {@code position}. Returns null if there
* are fewer than {@code position} headers.
*/
@Override public final String getHeaderField(int position) {
try {
return getResponse().getResponseHeaders().getHeaders().getValue(position);
} catch (IOException e) {
return null;
}
}
/**
* Returns the value of the field corresponding to the {@code fieldName}, or
* null if there is no such field. If the field has multiple values, the
* last value is returned.
*/
@Override public final String getHeaderField(String fieldName) {
try {
RawHeaders rawHeaders = getResponse().getResponseHeaders().getHeaders();
return fieldName == null ? rawHeaders.getStatusLine() : rawHeaders.get(fieldName);
} catch (IOException e) {
return null;
}
}
@Override public final String getHeaderFieldKey(int position) {
try {
return getResponse().getResponseHeaders().getHeaders().getFieldName(position);
} catch (IOException e) {
return null;
}
}
@Override public final Map<String, List<String>> getHeaderFields() {
try {
return getResponse().getResponseHeaders().getHeaders().toMultimap(true);
} catch (IOException e) {
return Collections.emptyMap();
}
}
@Override public final Map<String, List<String>> getRequestProperties() {
if (connected) {
throw new IllegalStateException(
"Cannot access request header fields after connection is set");
}
return rawRequestHeaders.toMultimap(false);
}
@Override public final InputStream getInputStream() throws IOException {
if (!doInput) {
throw new ProtocolException("This protocol does not support input");
}
HttpEngine response = getResponse();
// if the requested file does not exist, throw an exception formerly the
// Error page from the server was returned if the requested file was
// text/html this has changed to return FileNotFoundException for all
// file types
if (getResponseCode() >= HTTP_BAD_REQUEST) {
throw new FileNotFoundException(url.toString());
}
InputStream result = response.getResponseBody();
if (result == null) {
throw new ProtocolException("No response body exists; responseCode=" + getResponseCode());
}
return result;
}
@Override public final OutputStream getOutputStream() throws IOException {
connect();
OutputStream out = httpEngine.getRequestBody();
if (out == null) {
throw new ProtocolException("method does not support a request body: " + method);
} else if (httpEngine.hasResponse()) {
throw new ProtocolException("cannot write request body after response has been read");
}
return out;
}
@Override public final Permission getPermission() throws IOException {
String hostName = getURL().getHost();
int hostPort = Util.getEffectivePort(getURL());
if (usingProxy()) {
InetSocketAddress proxyAddress = (InetSocketAddress) client.getProxy().address();
hostName = proxyAddress.getHostName();
hostPort = proxyAddress.getPort();
}
return new SocketPermission(hostName + ":" + hostPort, "connect, resolve");
}
@Override public final String getRequestProperty(String field) {
if (field == null) {
return null;
}
return rawRequestHeaders.get(field);
}
@Override public void setConnectTimeout(int timeoutMillis) {
client.setConnectTimeout(timeoutMillis, TimeUnit.MILLISECONDS);
}
@Override public int getConnectTimeout() {
return client.getConnectTimeout();
}
@Override public void setReadTimeout(int timeoutMillis) {
client.setReadTimeout(timeoutMillis, TimeUnit.MILLISECONDS);
}
@Override public int getReadTimeout() {
return client.getReadTimeout();
}
private void initHttpEngine() throws IOException {
if (httpEngineFailure != null) {
throw httpEngineFailure;
} else if (httpEngine != null) {
return;
}
connected = true;
try {
if (doOutput) {
if (method.equals("GET")) {
// they are requesting a stream to write to. This implies a POST method
method = "POST";
} else if (!method.equals("POST") && !method.equals("PUT") && !method.equals("PATCH")) {
// If the request method is neither POST nor PUT nor PATCH, then you're not writing
throw new ProtocolException(method + " does not support writing");
}
}
httpEngine = newHttpEngine(method, rawRequestHeaders, null, null);
} catch (IOException e) {
httpEngineFailure = e;
throw e;
}
}
@Override public HttpURLConnection getHttpConnectionToCache() {
return this;
}
private HttpEngine newHttpEngine(String method, RawHeaders requestHeaders,
Connection connection, RetryableOutputStream requestBody) throws IOException {
if (url.getProtocol().equals("http")) {
return new HttpEngine(client, this, method, requestHeaders, connection, requestBody);
} else if (url.getProtocol().equals("https")) {
return new HttpsEngine(client, this, method, requestHeaders, connection, requestBody);
} else {
throw new AssertionError();
}
}
/**
* Aggressively tries to get the final HTTP response, potentially making
* many HTTP requests in the process in order to cope with redirects and
* authentication.
*/
private HttpEngine getResponse() throws IOException {
initHttpEngine();
if (httpEngine.hasResponse()) {
return httpEngine;
}
while (true) {
if (!execute(true)) {
continue;
}
Retry retry = processResponseHeaders();
if (retry == Retry.NONE) {
httpEngine.automaticallyReleaseConnectionToPool();
return httpEngine;
}
// The first request was insufficient. Prepare for another...
String retryMethod = method;
OutputStream requestBody = httpEngine.getRequestBody();
// Although RFC 2616 10.3.2 specifies that a HTTP_MOVED_PERM
// redirect should keep the same method, Chrome, Firefox and the
// RI all issue GETs when following any redirect.
int responseCode = httpEngine.getResponseCode();
if (responseCode == HTTP_MULT_CHOICE
|| responseCode == HTTP_MOVED_PERM
|| responseCode == HTTP_MOVED_TEMP
|| responseCode == HTTP_SEE_OTHER) {
retryMethod = "GET";
requestBody = null;
}
if (requestBody != null && !(requestBody instanceof RetryableOutputStream)) {
throw new HttpRetryException("Cannot retry streamed HTTP body", responseCode);
}
if (retry == Retry.DIFFERENT_CONNECTION) {
httpEngine.automaticallyReleaseConnectionToPool();
}
httpEngine.release(false);
httpEngine = newHttpEngine(retryMethod, rawRequestHeaders, httpEngine.getConnection(),
(RetryableOutputStream) requestBody);
if (requestBody == null) {
// Drop the Content-Length header when redirected from POST to GET.
httpEngine.getRequestHeaders().removeContentLength();
}
}
}
/**
* Sends a request and optionally reads a response. Returns true if the
* request was successfully executed, and false if the request can be
* retried. Throws an exception if the request failed permanently.
*/
private boolean execute(boolean readResponse) throws IOException {
try {
httpEngine.sendRequest();
if (readResponse) {
httpEngine.readResponse();
}
return true;
} catch (IOException e) {
if (handleFailure(e)) {
return false;
} else {
throw e;
}
}
}
/**
* Report and attempt to recover from {@code e}. Returns true if the HTTP
* engine was replaced and the request should be retried. Otherwise the
* failure is permanent.
*/
private boolean handleFailure(IOException e) throws IOException {
RouteSelector routeSelector = httpEngine.routeSelector;
if (routeSelector != null && httpEngine.connection != null) {
routeSelector.connectFailed(httpEngine.connection, e);
}
OutputStream requestBody = httpEngine.getRequestBody();
boolean canRetryRequestBody = requestBody == null
|| requestBody instanceof RetryableOutputStream;
if (routeSelector == null && httpEngine.connection == null // No connection.
|| routeSelector != null && !routeSelector.hasNext() // No more routes to attempt.
|| !isRecoverable(e)
|| !canRetryRequestBody) {
httpEngineFailure = e;
return false;
}
httpEngine.release(true);
RetryableOutputStream retryableOutputStream = (RetryableOutputStream) requestBody;
httpEngine = newHttpEngine(method, rawRequestHeaders, null, retryableOutputStream);
httpEngine.routeSelector = routeSelector; // Keep the same routeSelector.
return true;
}
private boolean isRecoverable(IOException e) {
// If the problem was a CertificateException from the X509TrustManager,
// do not retry, we didn't have an abrupt server initiated exception.
boolean sslFailure =
e instanceof SSLHandshakeException && e.getCause() instanceof CertificateException;
boolean protocolFailure = e instanceof ProtocolException;
return !sslFailure && !protocolFailure;
}
public HttpEngine getHttpEngine() {
return httpEngine;
}
enum Retry {
NONE,
SAME_CONNECTION,
DIFFERENT_CONNECTION
}
/**
* Returns the retry action to take for the current response headers. The
* headers, proxy and target URL for this connection may be adjusted to
* prepare for a follow up request.
*/
private Retry processResponseHeaders() throws IOException {
Proxy selectedProxy = httpEngine.connection != null
? httpEngine.connection.getRoute().getProxy()
: client.getProxy();
final int responseCode = getResponseCode();
switch (responseCode) {
case HTTP_PROXY_AUTH:
if (selectedProxy.type() != Proxy.Type.HTTP) {
throw new ProtocolException("Received HTTP_PROXY_AUTH (407) code while not using proxy");
}
// fall-through
case HTTP_UNAUTHORIZED:
boolean credentialsFound = HttpAuthenticator.processAuthHeader(client.getAuthenticator(),
getResponseCode(), httpEngine.getResponseHeaders().getHeaders(), rawRequestHeaders,
selectedProxy, url);
return credentialsFound ? Retry.SAME_CONNECTION : Retry.NONE;
case HTTP_MULT_CHOICE:
case HTTP_MOVED_PERM:
case HTTP_MOVED_TEMP:
case HTTP_SEE_OTHER:
case HTTP_TEMP_REDIRECT:
if (!getInstanceFollowRedirects()) {
return Retry.NONE;
}
if (++redirectionCount > MAX_REDIRECTS) {
throw new ProtocolException("Too many redirects: " + redirectionCount);
}
if (responseCode == HTTP_TEMP_REDIRECT && !method.equals("GET") && !method.equals("HEAD")) {
// "If the 307 status code is received in response to a request other than GET or HEAD,
// the user agent MUST NOT automatically redirect the request"
return Retry.NONE;
}
String location = getHeaderField("Location");
if (location == null) {
return Retry.NONE;
}
URL previousUrl = url;
url = new URL(previousUrl, location);
if (!url.getProtocol().equals("https") && !url.getProtocol().equals("http")) {
return Retry.NONE; // Don't follow redirects to unsupported protocols.
}
boolean sameProtocol = previousUrl.getProtocol().equals(url.getProtocol());
if (!sameProtocol && !client.getFollowProtocolRedirects()) {
return Retry.NONE; // This client doesn't follow redirects across protocols.
}
boolean sameHost = previousUrl.getHost().equals(url.getHost());
boolean samePort = getEffectivePort(previousUrl) == getEffectivePort(url);
if (sameHost && samePort && sameProtocol) {
return Retry.SAME_CONNECTION;
} else {
return Retry.DIFFERENT_CONNECTION;
}
default:
return Retry.NONE;
}
}
/** @see java.net.HttpURLConnection#setFixedLengthStreamingMode(int) */
@Override public final long getFixedContentLength() {
return fixedContentLength;
}
@Override public final int getChunkLength() {
return chunkLength;
}
@Override public final boolean usingProxy() {
if (selectedProxy != null) {
return isValidNonDirectProxy(selectedProxy);
}
// This behavior is a bit odd (but is probably justified by the
// oddness of the APIs involved). Before a connection is established,
// this method will return true only if this connection was explicitly
// opened with a Proxy. We don't attempt to query the ProxySelector
// at all.
return isValidNonDirectProxy(client.getProxy());
}
private static boolean isValidNonDirectProxy(Proxy proxy) {
return proxy != null && proxy.type() != Proxy.Type.DIRECT;
}
@Override public String getResponseMessage() throws IOException {
return getResponse().getResponseHeaders().getHeaders().getResponseMessage();
}
@Override public final int getResponseCode() throws IOException {
return getResponse().getResponseCode();
}
@Override public final void setRequestProperty(String field, String newValue) {
if (connected) {
throw new IllegalStateException("Cannot set request property after connection is made");
}
if (field == null) {
throw new NullPointerException("field == null");
}
if (newValue == null) {
// Silently ignore null header values for backwards compatibility with older
// android versions as well as with other URLConnection implementations.
//
// Some implementations send a malformed HTTP header when faced with
// such requests, we respect the spec and ignore the header.
Platform.get().logW("Ignoring header " + field + " because its value was null.");
return;
}
if ("X-Android-Transports".equals(field)) {
setTransports(newValue, false /* append */);
} else {
rawRequestHeaders.set(field, newValue);
}
}
@Override public final void addRequestProperty(String field, String value) {
if (connected) {
throw new IllegalStateException("Cannot add request property after connection is made");
}
if (field == null) {
throw new NullPointerException("field == null");
}
if (value == null) {
// Silently ignore null header values for backwards compatibility with older
// android versions as well as with other URLConnection implementations.
//
// Some implementations send a malformed HTTP header when faced with
// such requests, we respect the spec and ignore the header.
Platform.get().logW("Ignoring header " + field + " because its value was null.");
return;
}
if ("X-Android-Transports".equals(field)) {
setTransports(value, true /* append */);
} else {
rawRequestHeaders.add(field, value);
}
}
/*
* Splits and validates a comma-separated string of transports.
* When append == false, we require that the transport list contains "http/1.1".
*/
private void setTransports(String transportsString, boolean append) {
List<String> transportsList = new ArrayList<String>();
if (append) {
transportsList.addAll(client.getTransports());
}
for (String transport : transportsString.split(",", -1)) {
transportsList.add(transport);
}
client.setTransports(transportsList);
}
@Override public void setFixedLengthStreamingMode(int contentLength) {
setFixedLengthStreamingMode((long) contentLength);
}
// @Override Don't override: this overload method doesn't exist prior to Java 1.7.
public void setFixedLengthStreamingMode(long contentLength) {
if (super.connected) throw new IllegalStateException("Already connected");
if (chunkLength > 0) throw new IllegalStateException("Already in chunked mode");
if (contentLength < 0) throw new IllegalArgumentException("contentLength < 0");
this.fixedContentLength = contentLength;
super.fixedContentLength = (int) Math.min(contentLength, Integer.MAX_VALUE);
}
@Override public final void setSelectedProxy(Proxy proxy) {
this.selectedProxy = proxy;
}
}