Java tutorial
/** * Copyright 2012 Comcast Corporation * * 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.comcast.cns.io; import java.io.InputStream; import java.io.InputStreamReader; import org.apache.http.HttpEntity; import org.apache.http.HttpHost; import org.apache.http.HttpResponse; import org.apache.http.HttpVersion; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpPost; import org.apache.http.client.methods.HttpRequestBase; import org.apache.http.conn.params.ConnRoutePNames; import org.apache.http.conn.scheme.PlainSocketFactory; import org.apache.http.conn.scheme.Scheme; import org.apache.http.conn.scheme.SchemeRegistry; import org.apache.http.conn.ssl.SSLSocketFactory; import org.apache.http.entity.StringEntity; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.impl.conn.PoolingClientConnectionManager; import org.apache.http.params.BasicHttpParams; import org.apache.http.params.HttpConnectionParams; import org.apache.http.params.HttpParams; import org.apache.http.params.HttpProtocolParams; import org.apache.http.util.EntityUtils; import org.apache.log4j.Logger; import com.comcast.cmb.common.util.CMBErrorCodes; import com.comcast.cmb.common.util.CMBException; import com.comcast.cmb.common.util.CMBProperties; import com.comcast.cns.model.CNSMessage.CNSMessageStructure; import com.comcast.cns.model.CNSMessage.CNSMessageType; import com.comcast.cns.model.CNSSubscription.CnsSubscriptionProtocol; /** * Following class uses the HttpClient library version 4.2.1 * @author aseem, bwolf */ public class HTTPEndpointSyncPublisher extends AbstractEndpointPublisher { private final static SchemeRegistry schemeRegistry = new SchemeRegistry(); private final static PoolingClientConnectionManager cm; private final static HttpClient httpClient; static { int timeoutMillis = CMBProperties.getInstance().getCNSPublisherHttpTimeoutSeconds() * 1000; HttpParams params = new BasicHttpParams(); if (CMBProperties.getInstance().getCNSHttpProxy() != null && !CMBProperties.getInstance().getCNSHttpProxy().equals("")) { String p[] = CMBProperties.getInstance().getCNSHttpProxy().split(":"); if (p.length == 2) { HttpHost proxy = new HttpHost(p[0], Integer.parseInt(p[1]), "http"); params.setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy); } } HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1); schemeRegistry.register(new Scheme("http", 80, PlainSocketFactory.getSocketFactory())); schemeRegistry.register(new Scheme("https", 443, SSLSocketFactory.getSocketFactory())); HttpConnectionParams.setConnectionTimeout(params, timeoutMillis); HttpConnectionParams.setSoTimeout(params, timeoutMillis); cm = new PoolingClientConnectionManager(schemeRegistry); // increase max total connection to 250 cm.setMaxTotal(CMBProperties.getInstance().getCNSPublisherHttpEndpointConnectionPoolSize()); // increase default max connection per route to 20 cm.setDefaultMaxPerRoute(CMBProperties.getInstance().getCNSPublisherHttpEndpointConnectionsPerRouteSize()); httpClient = new DefaultHttpClient(cm, params); } private static Logger logger = Logger.getLogger(HTTPEndpointSyncPublisher.class); public static int getNumConnectionsInPool() { return cm.getTotalStats().getAvailable(); } @Override public void send() throws Exception { if ((message == null) || (endpoint == null)) { logger.debug("event=send_http_request error_code=MissingParameters endpoint=" + endpoint + "\" message=\"" + message + "\""); throw new Exception("Message and Endpoint must both be set"); } HttpPost httpPost = new HttpPost(endpoint); String msg = null; if (message.getMessageStructure() == CNSMessageStructure.json) { msg = message.getProtocolSpecificMessage(CnsSubscriptionProtocol.http); } else { msg = message.getMessage(); } if (!rawMessageDelivery && message.getMessageType() == CNSMessageType.Notification) { msg = com.comcast.cns.util.Util.generateMessageJson(message, CnsSubscriptionProtocol.http); } logger.debug("event=send_sync_http_request endpoint=" + endpoint + "\" message=\"" + msg + "\""); StringEntity stringEntity = new StringEntity(msg); httpPost.setEntity(stringEntity); composeHeader(httpPost); HttpResponse response = httpClient.execute(httpPost); int statusCode = response.getStatusLine().getStatusCode(); HttpEntity entity = response.getEntity(); // accept all 2xx status codes if (statusCode > 200 || statusCode >= 300) { if (entity != null) { InputStream instream = entity.getContent(); InputStreamReader responseReader = new InputStreamReader(instream); StringBuffer buffer = new StringBuffer(); char[] arr = new char[1024]; int size = 0; while ((size = responseReader.read(arr, 0, arr.length)) != -1) { buffer.append(arr, 0, size); } instream.close(); } logger.debug("event=http_post_error endpoint=" + endpoint + " error_code=" + statusCode); throw new CMBException(new CMBErrorCodes(statusCode, "HttpError"), "Unreachable endpoint " + endpoint + " returns status code " + statusCode); } else { if (entity != null) { EntityUtils.consume(entity); } } } private void composeHeader(HttpRequestBase httpRequest) { httpRequest.setHeader("x-amz-sns-message-type", this.getMessageType()); httpRequest.setHeader("x-amz-sns-message-id", this.getMessageId()); httpRequest.setHeader("x-amz-sns-topic-arn", this.getTopicArn()); httpRequest.setHeader("x-amz-sns-subscription-arn", this.getSubscriptionArn()); httpRequest.setHeader("User-Agent", "Cloud Notification Service Agent"); if (this.getRawMessageDelivery()) { httpRequest.addHeader("x-amz-raw-message", "true"); } } }