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/* * ConfigurationListener.java * * Copyright (c) 2011 FooBrew, Inc. * * 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 org.j2free.config; import java.util.concurrent.ExecutorService; import java.io.IOException; import java.io.InputStream; import java.lang.reflect.Constructor; import java.lang.reflect.Method; import java.net.InetAddress; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.Properties; import java.util.Scanner; import java.util.Set; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.ScheduledFuture; import java.util.concurrent.TimeUnit; import javax.mail.Authenticator; import javax.mail.PasswordAuthentication; import javax.mail.Session; import javax.servlet.ServletContext; import javax.servlet.ServletContextEvent; import javax.servlet.ServletContextListener; import org.apache.commons.configuration.CombinedConfiguration; import org.apache.commons.configuration.Configuration; import org.apache.commons.configuration.ConfigurationException; import org.apache.commons.configuration.DefaultConfigurationBuilder; import org.apache.commons.lang.StringUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.j2free.cache.FragmentCache; import org.j2free.email.EmailService.ContentType; import org.j2free.email.SimpleEmailService; import org.j2free.email.Template; import org.j2free.http.SimpleHttpService; import org.j2free.jsp.tags.FragmentCacheTag; import org.j2free.util.Global; import org.j2free.util.KeyValuePair; import org.j2free.util.Priority; import org.j2free.util.concurrent.ConcurrentHashSet; import static org.j2free.util.Constants.*; /** * If a <tt>Configuration</tt> is found and successfully loaded, then * the following items will be configured accordingly: * - <tt>RunMode</tt> * - <tt>InvokerFilter</tt> * - <tt>StaticJspServlet</tt> * - <tt>LogoutServlet</tt> * - <tt>ProxyServlet</tt> * - <tt>EntityAdminServlet</tt> * - <tt>Fragment Caching</tt> * - <tt>Task ScheduledExecutorService</tt> * - <tt>SimpleEmailService</tt> * - <tt>SimpleHttpService</tt> * - <tt>EmailErrorReporter</tt> * - <tt>Spymemcached</tt> * - <tt>Dynamic Reconfiguration</tt> * * Lacking a <tt>Configuration</tt> default values will be used, and * the above items will not be initialized. * * Finally, this method of configuration can be ignore entirely by * removing the <tt>servlet-mapping</tt>. * * The ServletContextListener contextInitialized methods are called before any filters * or servlets are instantiated. * * @see <tt>org.j2free.util.Constants</tt> for a list of configurable * properties. * * @author Ryan Wilson */ public class ConfigurationListener implements ServletContextListener { private final Log log = LogFactory.getLog(getClass()); private Runnable reconfigTask; private ScheduledFuture reconfigFuture; // Stores what properties from the config file are saved in the ServletContext, // so that they can be removed before reconfiguration private final ConcurrentHashSet<String> loadedConfigPropKeys = new ConcurrentHashSet(); /** * */ protected ServletContext context; /** * * @param event */ public synchronized void contextInitialized(ServletContextEvent event) { context = event.getServletContext(); // Get the configuration file String configPathTemp = (String) context.getInitParameter(INIT_PARAM_CONFIG_PATH); // Use the default path if it wasn't specified if (StringUtils.isBlank(configPathTemp)) configPathTemp = DEFAULT_CONFIG_PATH; // Finalize the config path (needs to be final for inner-Runnable below) final String configPath = configPathTemp; context.setAttribute(CONTEXT_ATTR_CONFIG_PATH, configPath); try { // Load the configuration DefaultConfigurationBuilder configBuilder = new DefaultConfigurationBuilder(); configBuilder.setFileName(configPath); final CombinedConfiguration config = configBuilder.getConfiguration(true); // Save the config where we can get at it later context.setAttribute(CONTEXT_ATTR_CONFIG, config); Global.put(CONTEXT_ATTR_CONFIG, config); // Determine the localhost String localhost = config.getString(PROP_LOCALHOST, "ip"); if (localhost.equalsIgnoreCase("ip")) { try { localhost = InetAddress.getLocalHost().getHostAddress(); log.info("Using localhost: " + localhost); } catch (Exception e) { log.warn("Error determining localhost", e); localhost = "localhost"; } } context.setAttribute(CONTEXT_ATTR_LOCALHOST, localhost); Global.put(CONTEXT_ATTR_LOCALHOST, localhost); loadedConfigPropKeys.add(CONTEXT_ATTR_LOCALHOST); // Set application context attributes for all config properties String prop, value; Iterator itr = config.getKeys(); while (itr.hasNext()) { prop = (String) itr.next(); value = config.getString(prop); // Anything with the value "localhost" will be set to the IP if possible value = (value.equals("localhost") ? localhost : value); log.debug("Config: " + prop + " = " + value); context.setAttribute(prop, value); loadedConfigPropKeys.add(prop); } // Run Mode configuration String runMode = config.getString(PROP_RUNMODE); try { RUN_MODE = RunMode.valueOf(runMode); } catch (Exception e) { log.warn("Error setting runmode, invalid value: " + runMode); } context.setAttribute("devMode", RUN_MODE != RunMode.PRODUCTION); loadedConfigPropKeys.add("devMode"); // Fragment Cache Configuration if (config.getBoolean(FragmentCache.Properties.ENABLED, false)) { log.info("Enabling fragment caching..."); FragmentCacheTag.enable(); // This is expected to be in seconds long temp = config.getLong(FragmentCache.Properties.REQUEST_TIMEOUT, -1l); if (temp != -1) { log.info("Setting FragmentCacheTag request timeout: " + temp); FragmentCacheTag.setRequestTimeout(temp); } // The property is in seconds, but WARNING_COMPUTE_DURATION does NOT use a TimeUnit, so it's in ms temp = config.getLong(FragmentCache.Properties.WARNING_DURATION, -1l); if (temp != -1) { log.info("Setting FragmentCacheTag warning duration: " + temp); FragmentCacheTag.setWarningComputeDuration(temp * 1000); } // Get the fragment cache names String[] cacheNames = config.getStringArray(FragmentCache.Properties.ENGINE_NAMES); for (String cacheName : cacheNames) { String cacheClassName = config .getString(String.format(FragmentCache.Properties.ENGINE_CLASS_TEMPLATE, cacheName)); try { // Load up the class Class<? extends FragmentCache> cacheClass = (Class<? extends FragmentCache>) Class .forName(cacheClassName); // Look for a constructor that takes a config Constructor<? extends FragmentCache> constructor = null; try { constructor = cacheClass.getConstructor(Configuration.class); } catch (Exception e) { } FragmentCache cache; // If we found the configuration constructor, use it if (constructor != null) cache = constructor.newInstance(config); else { // otherwise use a default no-args constructor log.warn("Could not find a " + cacheClass.getSimpleName() + " constructor that takes a Configuration, defaulting to no-args constructor"); cache = cacheClass.newInstance(); } // register the cache with the FragmentCacheTag using the config strategy-name, or the engineName // if a strategy-name is not specified log.info("Registering FragmentCache strategy: [name=" + cacheName + ", class=" + cacheClass.getName() + "]"); FragmentCacheTag.registerStrategy(cacheName, cache); } catch (Exception e) { log.error("Error enabling FragmentCache engine: " + cacheName, e); } } } else { // Have to call this here, because reconfiguration could turn // the cache off after it was previously enabled. FragmentCacheTag.disable(); } // For Task execution ScheduledExecutorService taskExecutor; if (config.getBoolean(PROP_TASK_EXECUTOR_ON, false)) { int threads = config.getInt(PROP_TASK_EXECUTOR_THREADS, DEFAULT_TASK_EXECUTOR_THREADS); if (threads == 1) taskExecutor = Executors.newSingleThreadScheduledExecutor(); else taskExecutor = Executors.newScheduledThreadPool(threads); context.setAttribute(CONTEXT_ATTR_TASK_MANAGER, taskExecutor); loadedConfigPropKeys.add(CONTEXT_ATTR_TASK_MANAGER); Global.put(CONTEXT_ATTR_TASK_MANAGER, taskExecutor); } else { // Not allowed to shutdown the taskExecutor if dynamic reconfig is enabled if (reconfigTask == null) { // Shutdown and remove references to the taskManager previously created taskExecutor = (ScheduledExecutorService) Global.get(CONTEXT_ATTR_TASK_MANAGER); if (taskExecutor != null) { taskExecutor.shutdown(); // will block until all tasks complete taskExecutor = null; Global.remove(CONTEXT_ATTR_TASK_MANAGER); } } else { // We could just log a warning that you can't do this, but the user // might not see that, so we're going to refuse to reset a configuration // that cannot be loaded in whole successfully. throw new ConfigurationException( "Cannot disable task execution service, dynamic reconfiguration is enabled!"); } } // Email Service if (config.getBoolean(PROP_MAIL_SERVICE_ON, false)) { if (!SimpleEmailService.isEnabled()) { // Get the SMTP properties Properties props = System.getProperties(); props.put(PROP_SMTP_HOST, config.getString(PROP_SMTP_HOST)); props.put(PROP_SMTP_PORT, config.getString(PROP_SMTP_PORT)); props.put(PROP_SMTP_AUTH, config.getString(PROP_SMTP_AUTH)); Session session; if (config.getBoolean(PROP_SMTP_AUTH)) { final String user = config.getString(PROP_SMTP_USER); final String pass = config.getString(PROP_SMTP_PASS); Authenticator auth = new Authenticator() { @Override public PasswordAuthentication getPasswordAuthentication() { return new PasswordAuthentication(user, pass); } }; session = Session.getInstance(props, auth); } else { session = Session.getInstance(props); } // Get the global headers Iterator headerNames = config.getKeys(PROP_MAIL_HEADER_PREFIX); List<KeyValuePair<String, String>> headers = new LinkedList<KeyValuePair<String, String>>(); String headerName; while (headerNames.hasNext()) { headerName = (String) headerNames.next(); headers.add(new KeyValuePair<String, String>(headerName, config.getString(headerName))); } // Initialize the service SimpleEmailService.init(session); SimpleEmailService.setGlobalHeaders(headers); // Set whether we actually send the e-mails SimpleEmailService.setDummyMode(config.getBoolean(PROP_MAIL_DUMMY_MODE, false)); // Set the failure policy String policy = config.getString(PROP_MAIL_ERROR_POLICY); if (policy != null) { if (policy.equals(VALUE_MAIL_POLICY_DISCARD)) { SimpleEmailService.setErrorPolicy(new SimpleEmailService.DiscardPolicy()); } else if (policy.equals(VALUE_MAIL_POLICY_REQUEUE)) { Priority priority = null; try { priority = Priority.valueOf(config.getString(PROP_MAIL_REQUEUE_PRIORITY)); } catch (Exception e) { log.warn("Error reading requeue policy priority: " + config.getString(PROP_MAIL_REQUEUE_PRIORITY, "") + ", using default"); } if (priority == null) SimpleEmailService.setErrorPolicy(new SimpleEmailService.RequeuePolicy()); else SimpleEmailService.setErrorPolicy(new SimpleEmailService.RequeuePolicy(priority)); } } // Parse templates String emailTemplateDir = config.getString(PROP_MAIL_TEMPLATE_DIR); // If the template if (StringUtils.isBlank(emailTemplateDir)) emailTemplateDir = DEFAULT_EMAIL_TEMPLATE_DIR; log.debug("Looking for e-mail templates in: " + emailTemplateDir); Set<String> templates = context.getResourcePaths(emailTemplateDir); // E-mail templates if (templates != null && !templates.isEmpty()) { log.debug("Found " + templates.size() + " templates"); String key; String defaultTemplate = config.getString(PROP_MAIL_DEFAULT_TEMPLATE, EMPTY); InputStream in; StringBuilder builder; Scanner scanner; try { Template template; String[] parts; ContentType contentType; for (String path : templates) { path = path.trim(); parts = path.split("\\."); contentType = ContentType.valueOfExt(parts[1]); try { in = context.getResourceAsStream(path.trim()); if (in != null && in.available() > 0) { scanner = new Scanner(in); builder = new StringBuilder(); while (scanner.hasNextLine()) { builder.append(scanner.nextLine()); if (contentType == ContentType.PLAIN) { builder.append("\n"); } } template = new Template(builder.toString(), contentType); key = parts[0].replace(emailTemplateDir, EMPTY); SimpleEmailService.registerTemplate(key, template, key.equals(defaultTemplate)); } } catch (IOException ioe) { log.error("Error loading e-mail template: " + path, ioe); } } } catch (Exception e) { log.error("Error loading e-mail templates", e); } } else log.debug("No e-mail templates found."); } } else if (SimpleEmailService.isEnabled()) { boolean shutdown = false; try { shutdown = SimpleEmailService.shutdown(30, TimeUnit.SECONDS); } catch (InterruptedException ie) { log.warn("Interrupted while shutting down SimpleEmailService"); } if (!shutdown) SimpleEmailService.shutdown(); } // QueuedHttpCallService if (config.getBoolean(PROP_HTTP_SRVC_ON, false)) { if (!SimpleHttpService.isEnabled()) // Don't double init... { int defaultThreadCount = Runtime.getRuntime().availableProcessors() + 1; // threads to use if unspecified SimpleHttpService.init(config.getInt(PROP_HTTP_SRVC_CORE_POOL, defaultThreadCount), config.getInt(PROP_HTTP_SRVC_MAX_POOL, defaultThreadCount), config.getLong(PROP_HTTP_SRVC_POOL_IDLE, DEFAULT_HTTP_SRVC_THREAD_IDLE), config.getInt(PROP_HTTP_SRVC_CONNECT_TOUT, DEFAULT_HTTP_SRVC_CONNECT_TOUT), config.getInt(PROP_HTTP_SRVE_SOCKET_TOUT, DEFAULT_HTTP_SRVE_SOCKET_TOUT)); } } else if (SimpleHttpService.isEnabled()) { boolean shutdown = false; try { // Try to shutdown the service while letting currently waiting tasks complete shutdown = SimpleHttpService.shutdown(30, TimeUnit.SECONDS); } catch (InterruptedException ie) { log.warn("Interrupted while waiting for SimpleHttpService to shutdown"); } if (!shutdown) { // But if that doesn't finish in 60 seconds, just cut it off int count = SimpleHttpService.shutdown().size(); log.warn("SimpleHttpService failed to shutdown in 60 seconds, so it was terminated with " + count + " tasks waiting"); } } // Spymemcached Client if (config.getBoolean(PROP_SPYMEMCACHED_ON, false)) { String addresses = config.getString(PROP_SPYMEMCACHED_ADDRESSES); if (addresses == null) { log.error("Error configuring spymemcached; enabled but no addresses!"); } else { try { // Reflect our way to the constructor, this is all so that the // spymemcached jar does not need to be included in a J2Free app // unless it is actually to be used. Class klass = Class.forName("net.spy.memcached.MemcachedClient"); Constructor constructor = klass.getConstructor(List.class); klass = Class.forName("net.spy.memcached.AddrUtil"); Method method = klass.getMethod("getAddresses", String.class); Object client = constructor.newInstance(method.invoke(null, addresses)); context.setAttribute(CONTEXT_ATTR_SPYMEMCACHED, client); loadedConfigPropKeys.add(CONTEXT_ATTR_SPYMEMCACHED); Global.put(CONTEXT_ATTR_SPYMEMCACHED, client); log.info("Spymemcached client created, connected to " + addresses); } catch (Exception e) { log.error("Error creating memcached client [addresses=" + addresses + "]", e); } } } else { // If a spymemcached client was previous created Object client = Global.get(CONTEXT_ATTR_SPYMEMCACHED); if (client != null) { try { // Reflect our way to the shutdown method Class klass = Class.forName("net.spy.memcached.MemcachedClient"); Method method = klass.getMethod("shutdown"); method.invoke(null, client); // and shut it down log.info("Spymemcached client shutdown"); } catch (Exception e) { log.error("Error shutting down spymemcached client", e); } // Then remove any references Global.remove(CONTEXT_ATTR_SPYMEMCACHED); client = null; } } } catch (ConfigurationException ce) { log.error("Error configuring app", ce); } } /** * * @param event */ public synchronized void contextDestroyed(ServletContextEvent event) { // Remove all properties from the ServletContext that were set in the // previous configuration. for (String key : loadedConfigPropKeys) context.removeAttribute(key); loadedConfigPropKeys.clear(); // Clear resources Global.clear(); if (SimpleEmailService.isEnabled()) { log.info("Shutting down SimpleEmailService..."); boolean emailOff = false; try { emailOff = SimpleEmailService.shutdown(2, TimeUnit.SECONDS); } catch (InterruptedException ie) { } if (!emailOff) SimpleEmailService.shutdown(); } if (SimpleHttpService.isEnabled()) { log.info("Shutting down SimpleHttpService..."); boolean httpOff = false; try { httpOff = SimpleHttpService.shutdown(2, TimeUnit.SECONDS); } catch (InterruptedException ie) { } if (!httpOff) SimpleHttpService.shutdown(); } ExecutorService taskExecutor = (ExecutorService) Global.get(CONTEXT_ATTR_TASK_MANAGER); if (taskExecutor != null) { log.info("Shutting down ExecutorService..."); List<Runnable> cancelledTasks = taskExecutor.shutdownNow(); if (cancelledTasks != null && !cancelledTasks.isEmpty()) { for (Runnable task : cancelledTasks) { log.warn("Cancelled task: " + task); } } } if (FragmentCacheTag.isEnabled()) { log.info("Destroying FragmentCache"); FragmentCacheTag.disable(); } } }