Java tutorial
/* * 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 org.apache.activemq.artemis.rest.queue.push; import javax.ws.rs.core.UriBuilder; import java.io.IOException; import org.apache.activemq.artemis.api.core.client.ClientMessage; import org.apache.activemq.artemis.jms.client.ConnectionFactoryOptions; import org.apache.activemq.artemis.rest.ActiveMQRestLogger; import org.apache.activemq.artemis.rest.queue.push.xml.BasicAuth; import org.apache.activemq.artemis.rest.queue.push.xml.PushRegistration; import org.apache.activemq.artemis.rest.queue.push.xml.XmlHttpHeader; import org.apache.activemq.artemis.rest.util.HttpMessageHelper; import org.apache.http.HttpException; import org.apache.http.HttpHost; import org.apache.http.HttpRequest; import org.apache.http.HttpRequestInterceptor; import org.apache.http.auth.AuthScheme; import org.apache.http.auth.AuthScope; import org.apache.http.auth.AuthState; import org.apache.http.auth.Credentials; import org.apache.http.auth.UsernamePasswordCredentials; import org.apache.http.client.CredentialsProvider; import org.apache.http.client.HttpClient; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.impl.auth.BasicScheme; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.protocol.HttpContext; import org.apache.http.protocol.HttpCoreContext; import org.jboss.resteasy.client.ClientRequest; import org.jboss.resteasy.client.ClientResponse; import org.jboss.resteasy.client.core.executors.ApacheHttpClient4Executor; import org.jboss.resteasy.specimpl.ResteasyUriBuilder; public class UriStrategy implements PushStrategy { ThreadSafeClientConnManager connManager = new ThreadSafeClientConnManager(); protected HttpClient client = new DefaultHttpClient(connManager); protected BasicHttpContext localContext; protected ApacheHttpClient4Executor executor = new ApacheHttpClient4Executor(client); protected PushRegistration registration; protected UriBuilder targetUri; protected String method; protected String contentType; protected ConnectionFactoryOptions jmsOptions; UriStrategy() { connManager.setDefaultMaxPerRoute(100); connManager.setMaxTotal(1000); } @Override public void setRegistration(PushRegistration reg) { this.registration = reg; } @Override public void start() throws Exception { initAuthentication(); method = registration.getTarget().getMethod(); if (method == null) method = "POST"; contentType = registration.getTarget().getType(); targetUri = ResteasyUriBuilder.fromTemplate(registration.getTarget().getHref()); } protected void initAuthentication() { if (registration.getAuthenticationMechanism() != null) { if (registration.getAuthenticationMechanism().getType() instanceof BasicAuth) { BasicAuth basic = (BasicAuth) registration.getAuthenticationMechanism().getType(); UsernamePasswordCredentials creds = new UsernamePasswordCredentials(basic.getUsername(), basic.getPassword()); AuthScope authScope = new AuthScope(AuthScope.ANY); ((DefaultHttpClient) client).getCredentialsProvider().setCredentials(authScope, creds); localContext = new BasicHttpContext(); // Generate BASIC scheme object and stick it to the local execution context BasicScheme basicAuth = new BasicScheme(); localContext.setAttribute("preemptive-auth", basicAuth); // Add as the first request interceptor ((DefaultHttpClient) client).addRequestInterceptor(new PreemptiveAuth(), 0); executor.setHttpContext(localContext); } } } @Override public void stop() { connManager.shutdown(); } @Override public void setJmsOptions(ConnectionFactoryOptions jmsOptions) { this.jmsOptions = jmsOptions; } @Override public boolean push(ClientMessage message) { ActiveMQRestLogger.LOGGER.debug("Pushing " + message); String uri = createUri(message); for (int i = 0; i < registration.getMaxRetries(); i++) { long wait = registration.getRetryWaitMillis(); System.out.println("Creating request from " + uri); ClientRequest request = executor.createRequest(uri); request.followRedirects(false); ActiveMQRestLogger.LOGGER.debug("Created request " + request); for (XmlHttpHeader header : registration.getHeaders()) { ActiveMQRestLogger.LOGGER .debug("Setting XmlHttpHeader: " + header.getName() + "=" + header.getValue()); request.header(header.getName(), header.getValue()); } HttpMessageHelper.buildMessage(message, request, contentType, jmsOptions); ClientResponse<?> res = null; try { ActiveMQRestLogger.LOGGER.debug(method + " " + uri); res = request.httpMethod(method); int status = res.getStatus(); ActiveMQRestLogger.LOGGER.debug("Status of push: " + status); if (status == 503) { String retryAfter = res.getStringHeaders().getFirst("Retry-After"); if (retryAfter != null) { wait = Long.parseLong(retryAfter) * 1000; } } else if (status == 307) { uri = res.getLocation().toString(); wait = 0; } else if ((status >= 200 && status < 299) || status == 303 || status == 304) { ActiveMQRestLogger.LOGGER.debug("Success"); return true; } else if (status >= 400) { switch (status) { case 400: // these usually mean the message you are trying to send is crap, let dead letter logic take over case 411: case 412: case 413: case 414: case 415: case 416: throw new RuntimeException("Something is wrong with the message, status returned: " + status + " for push registration of URI: " + uri); case 401: // might as well consider these critical failures and abort. Immediately signal to disable push registration depending on config case 402: case 403: case 405: case 406: case 407: case 417: case 505: return false; case 404: // request timeout, gone, and not found treat as a retry case 408: case 409: case 410: break; default: // all 50x requests just retry (except 505) break; } } } catch (Exception e) { ActiveMQRestLogger.LOGGER.failedToPushMessageToUri(uri, e); return false; } finally { if (res != null) res.releaseConnection(); } try { if (wait > 0) Thread.sleep(wait); } catch (InterruptedException e) { throw new RuntimeException("Interrupted"); } } return false; } protected String createUri(ClientMessage message) { String uri = targetUri.build().toString(); return uri; } static class PreemptiveAuth implements HttpRequestInterceptor { @Override public void process(final HttpRequest request, final HttpContext context) throws HttpException, IOException { AuthState authState = (AuthState) context.getAttribute(HttpClientContext.TARGET_AUTH_STATE); // If no auth scheme available yet, try to initialize it preemptively if (authState.getAuthScheme() == null) { AuthScheme authScheme = (AuthScheme) context.getAttribute("preemptive-auth"); CredentialsProvider credsProvider = (CredentialsProvider) context .getAttribute(HttpClientContext.CREDS_PROVIDER); HttpHost targetHost = (HttpHost) context.getAttribute(HttpCoreContext.HTTP_TARGET_HOST); if (authScheme != null) { Credentials creds = credsProvider .getCredentials(new AuthScope(targetHost.getHostName(), targetHost.getPort())); if (creds == null) { throw new HttpException("No credentials for preemptive authentication"); } authState.update(authScheme, creds); } } } } }