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/* * Copyright 2002-2008 the original author or authors. * * Licensed 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.duowan.common.rpc.client; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.util.HashMap; import java.util.Map; import java.util.zip.GZIPInputStream; import org.apache.commons.httpclient.Header; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpException; import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager; import org.apache.commons.httpclient.methods.ByteArrayRequestEntity; import org.apache.commons.httpclient.methods.PostMethod; import org.apache.commons.httpclient.params.HttpConnectionManagerParams; import org.apache.commons.io.IOUtils; import org.springframework.context.i18n.LocaleContext; import org.springframework.context.i18n.LocaleContextHolder; import org.springframework.util.StringUtils; /** * {@link HttpInvokerRequestExecutor} implementation that uses * <a href="http://jakarta.apache.org/commons/httpclient">Jakarta Commons HttpClient</a> * to execute POST requests. Requires Commons HttpClient 3.0 or higher. * * <p>Allows to use a pre-configured {@link org.apache.commons.httpclient.HttpClient} * instance, potentially with authentication, HTTP connection pooling, etc. * Also designed for easy subclassing, providing specific template methods. * * @author Juergen Hoeller * @author Mark Fisher * @since 1.1 * @see SimpleHttpInvokerRequestExecutor */ public class CommonsHttpInvokerRequestExecutor extends AbstractHttpInvokerRequestExecutor { private HttpClient httpClient; /** * Create a new CommonsHttpInvokerRequestExecutor with a default * HttpClient that uses a default MultiThreadedHttpConnectionManager. * Sets the socket read timeout to {@link #DEFAULT_READ_TIMEOUT_MILLISECONDS}. * @see org.apache.commons.httpclient.HttpClient * @see org.apache.commons.httpclient.MultiThreadedHttpConnectionManager */ public CommonsHttpInvokerRequestExecutor() { MultiThreadedHttpConnectionManager httpConnectionManager = new MultiThreadedHttpConnectionManager(); HttpConnectionManagerParams params = new HttpConnectionManagerParams(); params.setDefaultMaxConnectionsPerHost(300); params.setMaxTotalConnections(500); httpConnectionManager.setParams(params); this.httpClient = new HttpClient(httpConnectionManager); this.setReadTimeout(getReadTimeout()); this.setConnectionTimeout(getConnectionTimeout()); } /** * Create a new CommonsHttpInvokerRequestExecutor with the given * HttpClient instance. The socket read timeout of the provided * HttpClient will not be changed. * @param httpClient the HttpClient instance to use for this request executor */ public CommonsHttpInvokerRequestExecutor(HttpClient httpClient) { this.httpClient = httpClient; } /** * Set the HttpClient instance to use for this request executor. */ public void setHttpClient(HttpClient httpClient) { this.httpClient = httpClient; } /** * Return the HttpClient instance that this request executor uses. */ public HttpClient getHttpClient() { return this.httpClient; } /** * Create a PostMethod for the given configuration. * <p>The default implementation creates a standard PostMethod with * "application/x-java-serialized-object" as "Content-Type" header. * @param config the HTTP invoker configuration that specifies the * target service * @return the PostMethod instance * @throws IOException if thrown by I/O methods */ protected PostMethod createPostMethod(String serviceUrl) throws IOException { PostMethod postMethod = new PostMethod(serviceUrl); LocaleContext locale = LocaleContextHolder.getLocaleContext(); if (locale != null) { postMethod.addRequestHeader(HTTP_HEADER_ACCEPT_LANGUAGE, StringUtils.toLanguageTag(locale.getLocale())); } if (isAcceptGzipEncoding()) { postMethod.addRequestHeader(HTTP_HEADER_ACCEPT_ENCODING, ENCODING_GZIP); } return postMethod; } /** * Set the given serialized remote invocation as request body. * <p>The default implementation simply sets the serialized invocation * as the PostMethod's request body. This can be overridden, for example, * to write a specific encoding and potentially set appropriate HTTP * request headers. * @param config the HTTP invoker configuration that specifies the target service * @param postMethod the PostMethod to set the request body on * @param baos the ByteArrayOutputStream that contains the serialized * RemoteInvocation object * @throws IOException if thrown by I/O methods * @see org.apache.commons.httpclient.methods.PostMethod#setRequestBody(java.io.InputStream) * @see org.apache.commons.httpclient.methods.PostMethod#setRequestEntity * @see org.apache.commons.httpclient.methods.InputStreamRequestEntity */ protected void setRequestBody(PostMethod postMethod, byte[] parameters) throws IOException { ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); outputStream.write(parameters); outputStream.close(); postMethod.setRequestEntity(new ByteArrayRequestEntity(outputStream.toByteArray(), getContentType())); } /** * Execute the given PostMethod instance. * @param config the HTTP invoker configuration that specifies the target service * @param httpClient the HttpClient to execute on * @param postMethod the PostMethod to execute * @throws IOException if thrown by I/O methods * @see org.apache.commons.httpclient.HttpClient#executeMethod(org.apache.commons.httpclient.HttpMethod) */ protected void executePostMethod(HttpClient httpClient, PostMethod postMethod) throws IOException { httpClient.executeMethod(postMethod); } /** * Validate the given response as contained in the PostMethod object, * throwing an exception if it does not correspond to a successful HTTP response. * <p>Default implementation rejects any HTTP status code beyond 2xx, to avoid * parsing the response body and trying to deserialize from a corrupted stream. * @param config the HTTP invoker configuration that specifies the target service * @param postMethod the executed PostMethod to validate * @throws IOException if validation failed * @see org.apache.commons.httpclient.methods.PostMethod#getStatusCode() * @see org.apache.commons.httpclient.HttpException */ protected void validateResponse(PostMethod postMethod) throws IOException { if (postMethod.getStatusCode() >= 300) { throw new HttpException("Did not receive successful HTTP response: status code = " + postMethod.getStatusCode() + ", status message = [" + postMethod.getStatusText() + "]"); } } /** * Extract the response body from the given executed remote invocation * request. * <p>The default implementation simply fetches the PostMethod's response * body stream. If the response is recognized as GZIP response, the * InputStream will get wrapped in a GZIPInputStream. * @param config the HTTP invoker configuration that specifies the target service * @param postMethod the PostMethod to read the response body from * @return an InputStream for the response body * @throws IOException if thrown by I/O methods * @see #isGzipResponse * @see java.util.zip.GZIPInputStream * @see org.apache.commons.httpclient.methods.PostMethod#getResponseBodyAsStream() * @see org.apache.commons.httpclient.methods.PostMethod#getResponseHeader(String) */ protected InputStream getResponseBody(PostMethod postMethod) throws IOException { if (isGzipResponse(postMethod)) { return new GZIPInputStream(postMethod.getResponseBodyAsStream()); } else { return postMethod.getResponseBodyAsStream(); } } /** * Determine whether the given response indicates a GZIP response. * <p>Default implementation checks whether the HTTP "Content-Encoding" * header contains "gzip" (in any casing). * @param postMethod the PostMethod to check * @return whether the given response indicates a GZIP response */ protected boolean isGzipResponse(PostMethod postMethod) { Header encodingHeader = postMethod.getResponseHeader(HTTP_HEADER_CONTENT_ENCODING); return (encodingHeader != null && encodingHeader.getValue() != null && encodingHeader.getValue().toLowerCase().indexOf(ENCODING_GZIP) != -1); } @Override protected HttpResponse doExecuteRequest(String url, byte[] parameters) throws Exception { PostMethod postMethod = createPostMethod(url); try { setRequestBody(postMethod, parameters); executePostMethod(getHttpClient(), postMethod); validateResponse(postMethod); InputStream responseBody = getResponseBody(postMethod); ByteArrayInputStream responseBodyInput = new ByteArrayInputStream(IOUtils.toByteArray(responseBody)); HttpResponse response = new HttpResponse(); response.setBody(responseBodyInput); response.setHeaders(toHashMap(postMethod.getResponseHeaders())); return response; } finally { // Need to explicitly release because it might be pooled. postMethod.releaseConnection(); } } private Map<String, String> toHashMap(Header[] responseHeaders) { Map<String, String> r = new HashMap<String, String>(responseHeaders.length * 2); for (Header h : responseHeaders) { r.put(h.getName(), h.getValue()); } return r; } }