Java tutorial
/* * Copyright (c) 2015, WSO2 Inc. (http://www.wso2.org) All Rights Reserved. * * WSO2 Inc. 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 org.wso2.carbon.event.output.adapter.http; import org.apache.axiom.om.util.Base64; import org.apache.commons.httpclient.*; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.methods.*; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.http.HttpHost; import org.apache.http.conn.params.ConnRoutePNames; import org.wso2.carbon.context.PrivilegedCarbonContext; import org.wso2.carbon.event.output.adapter.core.EventAdapterUtil; import org.wso2.carbon.event.output.adapter.core.OutputEventAdapter; import org.wso2.carbon.event.output.adapter.core.OutputEventAdapterConfiguration; import org.wso2.carbon.event.output.adapter.core.exception.OutputEventAdapterException; import org.wso2.carbon.event.output.adapter.core.exception.TestConnectionNotSupportedException; import org.wso2.carbon.event.output.adapter.http.internal.util.HTTPEventAdapterConstants; import java.net.URL; import java.net.UnknownHostException; import java.util.HashMap; import java.util.Map; import java.util.concurrent.*; public class HTTPEventAdapter implements OutputEventAdapter { private static final Log log = LogFactory.getLog(OutputEventAdapter.class); private OutputEventAdapterConfiguration eventAdapterConfiguration; private Map<String, String> globalProperties; private static ExecutorService executorService; private String clientMethod; private int tenantId; private String contentType; private static HttpConnectionManager connectionManager; private HttpClient httpClient = null; private HostConfiguration hostConfiguration = null; public HTTPEventAdapter(OutputEventAdapterConfiguration eventAdapterConfiguration, Map<String, String> globalProperties) { this.eventAdapterConfiguration = eventAdapterConfiguration; this.globalProperties = globalProperties; this.clientMethod = eventAdapterConfiguration.getStaticProperties() .get(HTTPEventAdapterConstants.ADAPTER_HTTP_CLIENT_METHOD); } @Override public void init() throws OutputEventAdapterException { tenantId = PrivilegedCarbonContext.getThreadLocalCarbonContext().getTenantId(); //ExecutorService will be assigned if it is null if (executorService == null) { int minThread; int maxThread; long defaultKeepAliveTime; int jobQueSize; //If global properties are available those will be assigned else constant values will be assigned if (globalProperties.get(HTTPEventAdapterConstants.ADAPTER_MIN_THREAD_POOL_SIZE_NAME) != null) { minThread = Integer.parseInt( globalProperties.get(HTTPEventAdapterConstants.ADAPTER_MIN_THREAD_POOL_SIZE_NAME)); } else { minThread = HTTPEventAdapterConstants.ADAPTER_MIN_THREAD_POOL_SIZE; } if (globalProperties.get(HTTPEventAdapterConstants.ADAPTER_MAX_THREAD_POOL_SIZE_NAME) != null) { maxThread = Integer.parseInt( globalProperties.get(HTTPEventAdapterConstants.ADAPTER_MAX_THREAD_POOL_SIZE_NAME)); } else { maxThread = HTTPEventAdapterConstants.ADAPTER_MAX_THREAD_POOL_SIZE; } if (globalProperties.get(HTTPEventAdapterConstants.ADAPTER_KEEP_ALIVE_TIME_NAME) != null) { defaultKeepAliveTime = Integer .parseInt(globalProperties.get(HTTPEventAdapterConstants.ADAPTER_KEEP_ALIVE_TIME_NAME)); } else { defaultKeepAliveTime = HTTPEventAdapterConstants.DEFAULT_KEEP_ALIVE_TIME_IN_MILLIS; } if (globalProperties.get(HTTPEventAdapterConstants.ADAPTER_EXECUTOR_JOB_QUEUE_SIZE_NAME) != null) { jobQueSize = Integer.parseInt( globalProperties.get(HTTPEventAdapterConstants.ADAPTER_EXECUTOR_JOB_QUEUE_SIZE_NAME)); } else { jobQueSize = HTTPEventAdapterConstants.ADAPTER_EXECUTOR_JOB_QUEUE_SIZE; } executorService = new ThreadPoolExecutor(minThread, maxThread, defaultKeepAliveTime, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(jobQueSize)); //configurations for the httpConnectionManager which will be shared by every http adapter int defaultMaxConnectionsPerHost; int maxTotalConnections; if (globalProperties.get(HTTPEventAdapterConstants.DEFAULT_MAX_CONNECTIONS_PER_HOST) != null) { defaultMaxConnectionsPerHost = Integer .parseInt(globalProperties.get(HTTPEventAdapterConstants.DEFAULT_MAX_CONNECTIONS_PER_HOST)); } else { defaultMaxConnectionsPerHost = HTTPEventAdapterConstants.DEFAULT_DEFAULT_MAX_CONNECTIONS_PER_HOST; } if (globalProperties.get(HTTPEventAdapterConstants.MAX_TOTAL_CONNECTIONS) != null) { maxTotalConnections = Integer .parseInt(globalProperties.get(HTTPEventAdapterConstants.MAX_TOTAL_CONNECTIONS)); } else { maxTotalConnections = HTTPEventAdapterConstants.DEFAULT_MAX_TOTAL_CONNECTIONS; } connectionManager = new MultiThreadedHttpConnectionManager(); connectionManager.getParams().setDefaultMaxConnectionsPerHost(defaultMaxConnectionsPerHost); connectionManager.getParams().setMaxTotalConnections(maxTotalConnections); } } @Override public void testConnect() throws TestConnectionNotSupportedException { throw new TestConnectionNotSupportedException("Test connection is not available"); } @Override public void connect() { this.checkHTTPClientInit(eventAdapterConfiguration.getStaticProperties()); } @Override public void publish(Object message, Map<String, String> dynamicProperties) { //Load dynamic properties String url = dynamicProperties.get(HTTPEventAdapterConstants.ADAPTER_MESSAGE_URL); String username = dynamicProperties.get(HTTPEventAdapterConstants.ADAPTER_USERNAME); String password = dynamicProperties.get(HTTPEventAdapterConstants.ADAPTER_PASSWORD); Map<String, String> headers = this .extractHeaders(dynamicProperties.get(HTTPEventAdapterConstants.ADAPTER_HEADERS)); String payload = message.toString(); try { executorService.submit(new HTTPSender(url, payload, username, password, headers, httpClient)); } catch (RejectedExecutionException e) { EventAdapterUtil.logAndDrop(eventAdapterConfiguration.getName(), message, "Job queue is full", e, log, tenantId); } } @Override public void disconnect() { //not required } @Override public void destroy() { //not required } @Override public boolean isPolled() { return false; } private void checkHTTPClientInit(Map<String, String> staticProperties) { if (this.httpClient != null) { return; } synchronized (HTTPEventAdapter.class) { if (this.httpClient != null) { return; } httpClient = new HttpClient(connectionManager); String proxyHost = staticProperties.get(HTTPEventAdapterConstants.ADAPTER_PROXY_HOST); String proxyPort = staticProperties.get(HTTPEventAdapterConstants.ADAPTER_PROXY_PORT); if (proxyHost != null && proxyHost.trim().length() > 0) { try { HttpHost host = new HttpHost(proxyHost, Integer.parseInt(proxyPort)); this.httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, host); } catch (NumberFormatException e) { log.error("Invalid proxy port: " + proxyPort + ", " + "ignoring proxy settings for HTTP output event adaptor..."); } } String messageFormat = eventAdapterConfiguration.getMessageFormat(); if (messageFormat.equalsIgnoreCase("json")) { contentType = "application/json"; } else if (messageFormat.equalsIgnoreCase("text")) { contentType = "text/plain"; } else { contentType = "text/xml"; } } } private Map<String, String> extractHeaders(String headers) { if (headers == null || headers.trim().length() == 0) { return null; } String[] entries = headers.split(HTTPEventAdapterConstants.HEADER_SEPARATOR); String[] keyValue; Map<String, String> result = new HashMap<String, String>(); for (String header : entries) { try { keyValue = header.split(HTTPEventAdapterConstants.ENTRY_SEPARATOR, 2); result.put(keyValue[0].trim(), keyValue[1].trim()); } catch (Exception e) { log.warn("Header property '" + header + "' is not defined in the correct format.", e); } } return result; } /** * This class represents a job to send an HTTP request to a target URL. */ class HTTPSender implements Runnable { private String url; private String payload; private String username; private String password; private Map<String, String> headers; private HttpClient httpClient; public HTTPSender(String url, String payload, String username, String password, Map<String, String> headers, HttpClient httpClient) { this.url = url; this.payload = payload; this.username = username; this.password = password; this.headers = headers; this.httpClient = httpClient; } public String getUrl() { return url; } public String getPayload() { return payload; } public String getUsername() { return username; } public String getPassword() { return password; } public Map<String, String> getHeaders() { return headers; } public HttpClient getHttpClient() { return httpClient; } public void run() { EntityEnclosingMethod method = null; try { if (clientMethod.equalsIgnoreCase(HTTPEventAdapterConstants.CONSTANT_HTTP_PUT)) { method = new PutMethod(this.getUrl()); } else { method = new PostMethod(this.getUrl()); } if (hostConfiguration == null) { URL hostUrl = new URL(this.getUrl()); hostConfiguration = new HostConfiguration(); hostConfiguration.setHost(hostUrl.getHost(), hostUrl.getPort(), hostUrl.getProtocol()); } method.setRequestEntity(new StringRequestEntity(this.getPayload(), contentType, "UTF-8")); if (this.getUsername() != null && this.getUsername().trim().length() > 0) { method.setRequestHeader("Authorization", "Basic " + Base64.encode( (this.getUsername() + HTTPEventAdapterConstants.ENTRY_SEPARATOR + this.getPassword()) .getBytes())); } if (this.getHeaders() != null) { for (Map.Entry<String, String> header : this.getHeaders().entrySet()) { method.setRequestHeader(header.getKey(), header.getValue()); } } this.getHttpClient().executeMethod(hostConfiguration, method); } catch (UnknownHostException e) { EventAdapterUtil.logAndDrop(eventAdapterConfiguration.getName(), this.getPayload(), "Cannot connect to " + this.getUrl(), e, log, tenantId); } catch (Throwable e) { EventAdapterUtil.logAndDrop(eventAdapterConfiguration.getName(), this.getPayload(), null, e, log, tenantId); } finally { if (method != null) { method.releaseConnection(); } } } } }