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/* * Copyright 2004-2005 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 grails.plugins; import grails.util.Environment; import groovy.lang.GroovyClassLoader; import groovy.lang.GroovySystem; import groovy.lang.MetaClassRegistry; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.codehaus.groovy.control.CompilationFailedException; import grails.core.GrailsApplication; import org.grails.core.io.CachingPathMatchingResourcePatternResolver; import org.grails.plugins.*; import org.grails.spring.DefaultRuntimeSpringConfiguration; import org.grails.spring.RuntimeSpringConfiguration; import org.grails.core.exceptions.GrailsConfigurationException; import org.grails.io.support.GrailsResourceUtils; import grails.plugins.exceptions.PluginException; import grails.core.support.ParentApplicationContextAware; import org.codehaus.groovy.runtime.DefaultGroovyMethods; import org.codehaus.groovy.runtime.IOGroovyMethods; import org.springframework.beans.BeansException; import org.springframework.context.ApplicationContext; import org.springframework.context.ApplicationContextAware; import org.springframework.context.support.GenericApplicationContext; import org.springframework.core.io.Resource; import org.springframework.core.io.support.PathMatchingResourcePatternResolver; import org.springframework.util.Assert; import java.io.IOException; import java.lang.reflect.Modifier; import java.math.BigDecimal; import java.math.BigInteger; import java.net.URI; import java.net.URL; import java.util.*; /** * <p>Handles the loading and management of plug-ins in the Grails system. * A plugin is just like a normal Grails application except that it contains a file ending * in *Plugin.groovy in the root of the directory. * <p/> * <p>A Plugin class is a Groovy class that has a version and optionally closures * called doWithSpring, doWithContext and doWithWebDescriptor * <p/> * <p>The doWithSpring closure uses the BeanBuilder syntax (@see grails.spring.BeanBuilder) to * provide runtime configuration of Grails via Spring * <p/> * <p>The doWithContext closure is called after the Spring ApplicationContext is built and accepts * a single argument (the ApplicationContext) * <p/> * <p>The doWithWebDescriptor uses mark-up building to provide additional functionality to the web.xml * file * <p/> * <p> Example: * <pre> * class ClassEditorGrailsPlugin { * def version = '1.1' * def doWithSpring = { application -> * classEditor(org.springframework.beans.propertyeditors.ClassEditor, application.classLoader) * } * } * </pre> * <p/> * <p>A plugin can also define "dependsOn" and "evict" properties that specify what plugins the plugin * depends on and which ones it is incompatible with and should evict * * @author Graeme Rocher * @since 0.4 */ public class DefaultGrailsPluginManager extends AbstractGrailsPluginManager { private static final Log LOG = LogFactory.getLog(DefaultGrailsPluginManager.class); protected static final Class<?>[] COMMON_CLASSES = { Boolean.class, Byte.class, Character.class, Class.class, Double.class, Float.class, Integer.class, Long.class, Number.class, Short.class, String.class, BigInteger.class, BigDecimal.class, URL.class, URI.class }; private List<GrailsPlugin> delayedLoadPlugins = new LinkedList<GrailsPlugin>(); private ApplicationContext parentCtx; private PathMatchingResourcePatternResolver resolver; private Map<GrailsPlugin, String[]> delayedEvictions = new HashMap<GrailsPlugin, String[]>(); private Map<String, Set<GrailsPlugin>> pluginToObserverMap = new HashMap<String, Set<GrailsPlugin>>(); private PluginFilter pluginFilter; private static final String GRAILS_PLUGIN_SUFFIX = "GrailsPlugin"; private List<GrailsPlugin> userPlugins = new ArrayList<GrailsPlugin>(); public DefaultGrailsPluginManager(String resourcePath, GrailsApplication application) { super(application); Assert.notNull(application, "Argument [application] cannot be null!"); resolver = CachingPathMatchingResourcePatternResolver.INSTANCE; try { pluginResources = resolver.getResources(resourcePath); } catch (IOException ioe) { LOG.debug("Unable to load plugins for resource path " + resourcePath, ioe); } //corePlugins = new PathMatchingResourcePatternResolver().getResources("classpath:org/codehaus/groovy/grails/**/plugins/**GrailsPlugin.groovy"); this.application = application; setPluginFilter(); } public DefaultGrailsPluginManager(String[] pluginResources, GrailsApplication application) { super(application); resolver = CachingPathMatchingResourcePatternResolver.INSTANCE; List<Resource> resourceList = new ArrayList<Resource>(); for (String resourcePath : pluginResources) { try { resourceList.addAll(Arrays.asList(resolver.getResources(resourcePath))); } catch (IOException ioe) { LOG.debug("Unable to load plugins for resource path " + resourcePath, ioe); } } this.pluginResources = resourceList.toArray(new Resource[resourceList.size()]); this.application = application; setPluginFilter(); } public DefaultGrailsPluginManager(Class<?>[] plugins, GrailsApplication application) { super(application); pluginClasses = plugins; resolver = CachingPathMatchingResourcePatternResolver.INSTANCE; //this.corePlugins = new PathMatchingResourcePatternResolver().getResources("classpath:org/codehaus/groovy/grails/**/plugins/**GrailsPlugin.groovy"); this.application = application; setPluginFilter(); } public DefaultGrailsPluginManager(Resource[] pluginFiles, GrailsApplication application) { super(application); resolver = CachingPathMatchingResourcePatternResolver.INSTANCE; pluginResources = pluginFiles; this.application = application; setPluginFilter(); } public DefaultGrailsPluginManager(GrailsApplication application) { super(application); } public GrailsPlugin[] getUserPlugins() { return userPlugins.toArray(new GrailsPlugin[userPlugins.size()]); } private void setPluginFilter() { pluginFilter = new PluginFilterRetriever().getPluginFilter(application.getConfig()); } /** * @deprecated Will be removed in a future version of Grails */ @Deprecated public void startPluginChangeScanner() { // do nothing } /** * @deprecated Will be removed in a future version of Grails */ @Deprecated public void stopPluginChangeScanner() { // do nothing } public void refreshPlugin(String name) { if (hasGrailsPlugin(name)) { getGrailsPlugin(name).refresh(); } } public Collection<GrailsPlugin> getPluginObservers(GrailsPlugin plugin) { Assert.notNull(plugin, "Argument [plugin] cannot be null"); Collection<GrailsPlugin> c = pluginToObserverMap.get(plugin.getName()); // Add any wildcard observers. Collection<GrailsPlugin> wildcardObservers = pluginToObserverMap.get("*"); if (wildcardObservers != null) { if (c != null) { c.addAll(wildcardObservers); } else { c = wildcardObservers; } } if (c != null) { // Make sure this plugin is not observing itself! c.remove(plugin); return c; } return Collections.emptySet(); } @SuppressWarnings("rawtypes") public void informObservers(String pluginName, Map event) { GrailsPlugin plugin = getGrailsPlugin(pluginName); if (plugin == null) { return; } if (!plugin.isEnabled(applicationContext.getEnvironment().getActiveProfiles())) return; for (GrailsPlugin observingPlugin : getPluginObservers(plugin)) { if (!observingPlugin.isEnabled(applicationContext.getEnvironment().getActiveProfiles())) continue; observingPlugin.notifyOfEvent(event); } } /* (non-Javadoc) * @see grails.plugins.GrailsPluginManager#loadPlugins() */ public void loadPlugins() throws PluginException { if (initialised) { return; } ClassLoader gcl = application.getClassLoader(); attemptLoadPlugins(gcl); if (!delayedLoadPlugins.isEmpty()) { loadDelayedPlugins(); } if (!delayedEvictions.isEmpty()) { processDelayedEvictions(); } pluginList = sortPlugins(pluginList); initializePlugins(); initialised = true; } protected List<GrailsPlugin> sortPlugins(List<GrailsPlugin> toSort) { /* http://en.wikipedia.org/wiki/Topological_sorting * * L ? Empty list that will contain the sorted nodes S ? Set of all nodes function visit(node n) if n has not been visited yet then mark n as visited for each node m with an edge from n to m do visit(m) add n to L for each node n in S do visit(n) */ List<GrailsPlugin> sortedPlugins = new ArrayList<GrailsPlugin>(toSort.size()); Set<GrailsPlugin> visitedPlugins = new HashSet<GrailsPlugin>(); Map<GrailsPlugin, List<GrailsPlugin>> loadOrderDependencies = resolveLoadDependencies(toSort); for (GrailsPlugin plugin : toSort) { visitTopologicalSort(plugin, sortedPlugins, visitedPlugins, loadOrderDependencies); } return sortedPlugins; } protected Map<GrailsPlugin, List<GrailsPlugin>> resolveLoadDependencies(List<GrailsPlugin> plugins) { Map<GrailsPlugin, List<GrailsPlugin>> loadOrderDependencies = new HashMap<GrailsPlugin, List<GrailsPlugin>>(); for (GrailsPlugin plugin : plugins) { if (plugin.getLoadAfterNames() != null) { List<GrailsPlugin> loadDepsForPlugin = loadOrderDependencies.get(plugin); if (loadDepsForPlugin == null) { loadDepsForPlugin = new ArrayList<GrailsPlugin>(); loadOrderDependencies.put(plugin, loadDepsForPlugin); } for (String pluginName : plugin.getLoadAfterNames()) { GrailsPlugin loadAfterPlugin = getGrailsPlugin(pluginName); if (loadAfterPlugin != null) { loadDepsForPlugin.add(loadAfterPlugin); } } } for (String loadBefore : plugin.getLoadBeforeNames()) { GrailsPlugin loadBeforePlugin = getGrailsPlugin(loadBefore); if (loadBeforePlugin != null) { List<GrailsPlugin> loadDepsForPlugin = loadOrderDependencies.get(loadBeforePlugin); if (loadDepsForPlugin == null) { loadDepsForPlugin = new ArrayList<GrailsPlugin>(); loadOrderDependencies.put(loadBeforePlugin, loadDepsForPlugin); } loadDepsForPlugin.add(plugin); } } } return loadOrderDependencies; } private void visitTopologicalSort(GrailsPlugin plugin, List<GrailsPlugin> sortedPlugins, Set<GrailsPlugin> visitedPlugins, Map<GrailsPlugin, List<GrailsPlugin>> loadOrderDependencies) { if (plugin != null && !visitedPlugins.contains(plugin)) { visitedPlugins.add(plugin); List<GrailsPlugin> loadDepsForPlugin = loadOrderDependencies.get(plugin); if (loadDepsForPlugin != null) { for (GrailsPlugin dependentPlugin : loadDepsForPlugin) { visitTopologicalSort(dependentPlugin, sortedPlugins, visitedPlugins, loadOrderDependencies); } } sortedPlugins.add(plugin); } } private void attemptLoadPlugins(ClassLoader gcl) { // retrieve load core plugins first List<GrailsPlugin> grailsCorePlugins = loadCorePlugins ? findCorePlugins() : new ArrayList<GrailsPlugin>(); List<GrailsPlugin> grailsUserPlugins = findUserPlugins(gcl); userPlugins = grailsUserPlugins; List<GrailsPlugin> allPlugins = new ArrayList<GrailsPlugin>(grailsCorePlugins); allPlugins.addAll(grailsUserPlugins); //filtering applies to user as well as core plugins List<GrailsPlugin> filteredPlugins = getPluginFilter().filterPluginList(allPlugins); //make sure core plugins are loaded first List<GrailsPlugin> orderedCorePlugins = new ArrayList<GrailsPlugin>(); List<GrailsPlugin> orderedUserPlugins = new ArrayList<GrailsPlugin>(); for (GrailsPlugin plugin : filteredPlugins) { if (grailsCorePlugins != null) { if (grailsCorePlugins.contains(plugin)) { orderedCorePlugins.add(plugin); } else { orderedUserPlugins.add(plugin); } } } List<GrailsPlugin> orderedPlugins = new ArrayList<GrailsPlugin>(); orderedPlugins.addAll(orderedCorePlugins); orderedPlugins.addAll(orderedUserPlugins); for (GrailsPlugin plugin : orderedPlugins) { attemptPluginLoad(plugin); } } private List<GrailsPlugin> findCorePlugins() { CorePluginFinder finder = new CorePluginFinder(application); finder.setParentApplicationContext(parentCtx); List<GrailsPlugin> grailsCorePlugins = new ArrayList<GrailsPlugin>(); final Class<?>[] corePluginClasses = finder.getPluginClasses(); for (Class<?> pluginClass : corePluginClasses) { if (pluginClass != null && !Modifier.isAbstract(pluginClass.getModifiers()) && pluginClass != DefaultGrailsPlugin.class) { final BinaryGrailsPluginDescriptor binaryDescriptor = finder.getBinaryDescriptor(pluginClass); GrailsPlugin plugin; if (binaryDescriptor != null) { plugin = createBinaryGrailsPlugin(pluginClass, binaryDescriptor); } else { plugin = createGrailsPlugin(pluginClass); } plugin.setApplicationContext(applicationContext); grailsCorePlugins.add(plugin); } } return grailsCorePlugins; } private GrailsPlugin createBinaryGrailsPlugin(Class<?> pluginClass, BinaryGrailsPluginDescriptor binaryDescriptor) { return new BinaryGrailsPlugin(pluginClass, binaryDescriptor, application); } protected GrailsPlugin createGrailsPlugin(Class<?> pluginClass) { return new DefaultGrailsPlugin(pluginClass, application); } protected GrailsPlugin createGrailsPlugin(Class<?> pluginClass, Resource resource) { return new DefaultGrailsPlugin(pluginClass, resource, application); } private List<GrailsPlugin> findUserPlugins(ClassLoader gcl) { List<GrailsPlugin> grailsUserPlugins = new ArrayList<GrailsPlugin>(); LOG.info("Attempting to load [" + pluginResources.length + "] user defined plugins"); for (Resource r : pluginResources) { Class<?> pluginClass = loadPluginClass(gcl, r); if (isGrailsPlugin(pluginClass)) { GrailsPlugin plugin = createGrailsPlugin(pluginClass, r); //attemptPluginLoad(plugin); grailsUserPlugins.add(plugin); } else { LOG.warn("Class [" + pluginClass + "] not loaded as plug-in. Grails plug-ins must end with the convention 'GrailsPlugin'!"); } } for (Class<?> pluginClass : pluginClasses) { if (isGrailsPlugin(pluginClass)) { GrailsPlugin plugin = createGrailsPlugin(pluginClass); //attemptPluginLoad(plugin); grailsUserPlugins.add(plugin); } else { LOG.warn("Class [" + pluginClass + "] not loaded as plug-in. Grails plug-ins must end with the convention 'GrailsPlugin'!"); } } return grailsUserPlugins; } private boolean isGrailsPlugin(Class<?> pluginClass) { return pluginClass != null && pluginClass.getName().endsWith(GRAILS_PLUGIN_SUFFIX); } private void processDelayedEvictions() { for (Map.Entry<GrailsPlugin, String[]> entry : delayedEvictions.entrySet()) { GrailsPlugin plugin = entry.getKey(); for (String pluginName : entry.getValue()) { evictPlugin(plugin, pluginName); } } } private void initializePlugins() { for (Object plugin : plugins.values()) { if (plugin instanceof ApplicationContextAware) { ((ApplicationContextAware) plugin).setApplicationContext(applicationContext); } } } /** * This method will attempt to load that plug-ins not loaded in the first pass */ private void loadDelayedPlugins() { while (!delayedLoadPlugins.isEmpty()) { GrailsPlugin plugin = delayedLoadPlugins.remove(0); if (areDependenciesResolved(plugin)) { if (!hasValidPluginsToLoadBefore(plugin)) { registerPlugin(plugin); } else { delayedLoadPlugins.add(plugin); } } else { // ok, it still hasn't resolved the dependency after the initial // load of all plugins. All hope is not lost, however, so lets first // look inside the remaining delayed loads before giving up boolean foundInDelayed = false; for (GrailsPlugin remainingPlugin : delayedLoadPlugins) { if (isDependentOn(plugin, remainingPlugin)) { foundInDelayed = true; break; } } if (foundInDelayed) { delayedLoadPlugins.add(plugin); } else { failedPlugins.put(plugin.getName(), plugin); LOG.warn("WARNING: Plugin [" + plugin.getName() + "] cannot be loaded because its dependencies [" + DefaultGroovyMethods.inspect(plugin.getDependencyNames()) + "] cannot be resolved"); } } } } private boolean hasValidPluginsToLoadBefore(GrailsPlugin plugin) { String[] loadAfterNames = plugin.getLoadAfterNames(); for (Object delayedLoadPlugin : delayedLoadPlugins) { GrailsPlugin other = (GrailsPlugin) delayedLoadPlugin; for (String name : loadAfterNames) { if (other.getName().equals(name)) { return hasDelayedDependencies(other) || areDependenciesResolved(other); } } } return false; } private boolean hasDelayedDependencies(GrailsPlugin other) { String[] dependencyNames = other.getDependencyNames(); for (String dependencyName : dependencyNames) { for (GrailsPlugin grailsPlugin : delayedLoadPlugins) { if (grailsPlugin.getName().equals(dependencyName)) return true; } } return false; } /** * Checks whether the first plugin is dependant on the second plugin. * * @param plugin The plugin to check * @param dependency The plugin which the first argument may be dependant on * @return true if it is */ private boolean isDependentOn(GrailsPlugin plugin, GrailsPlugin dependency) { for (String name : plugin.getDependencyNames()) { String requiredVersion = plugin.getDependentVersion(name); if (name.equals(dependency.getName()) && GrailsVersionUtils.isValidVersion(dependency.getVersion(), requiredVersion)) return true; } return false; } private boolean areDependenciesResolved(GrailsPlugin plugin) { for (String name : plugin.getDependencyNames()) { if (!hasGrailsPlugin(name, plugin.getDependentVersion(name))) { return false; } } return true; } /** * Returns true if there are no plugins left that should, if possible, be loaded before this plugin. * * @param plugin The plugin * @return true if there are */ private boolean areNoneToLoadBefore(GrailsPlugin plugin) { for (String name : plugin.getLoadAfterNames()) { if (getGrailsPlugin(name) == null) { return false; } } return true; } private Class<?> loadPluginClass(ClassLoader cl, Resource r) { Class<?> pluginClass; if (cl instanceof GroovyClassLoader) { try { if (LOG.isInfoEnabled()) { LOG.info("Parsing & compiling " + r.getFilename()); } pluginClass = ((GroovyClassLoader) cl) .parseClass(IOGroovyMethods.getText(r.getInputStream(), "UTF-8")); } catch (CompilationFailedException e) { throw new PluginException("Error compiling plugin [" + r.getFilename() + "] " + e.getMessage(), e); } catch (IOException e) { throw new PluginException("Error reading plugin [" + r.getFilename() + "] " + e.getMessage(), e); } } else { String className = null; try { className = GrailsResourceUtils.getClassName(r.getFile().getAbsolutePath()); } catch (IOException e) { throw new PluginException( "Cannot find plugin class [" + className + "] resource: [" + r.getFilename() + "]", e); } try { pluginClass = Class.forName(className, true, cl); } catch (ClassNotFoundException e) { throw new PluginException( "Cannot find plugin class [" + className + "] resource: [" + r.getFilename() + "]", e); } } return pluginClass; } /** * Attempts to load a plugin based on its dependencies. If a plugin's dependencies cannot be resolved * it will add it to the list of dependencies to be resolved later. * * @param plugin The plugin */ private void attemptPluginLoad(GrailsPlugin plugin) { if (areDependenciesResolved(plugin) && areNoneToLoadBefore(plugin)) { registerPlugin(plugin); } else { delayedLoadPlugins.add(plugin); } } private void registerPlugin(GrailsPlugin plugin) { if (!canRegisterPlugin(plugin)) { if (LOG.isInfoEnabled()) { LOG.info("Grails plugin " + plugin + " is disabled and was not loaded"); } return; } if (LOG.isInfoEnabled()) { LOG.info("Grails plug-in [" + plugin.getName() + "] with version [" + plugin.getVersion() + "] loaded successfully"); } if (plugin instanceof ParentApplicationContextAware) { ((ParentApplicationContextAware) plugin).setParentApplicationContext(parentCtx); } plugin.setManager(this); String[] evictionNames = plugin.getEvictionNames(); if (evictionNames.length > 0) { delayedEvictions.put(plugin, evictionNames); } String[] observedPlugins = plugin.getObservedPluginNames(); for (String observedPlugin : observedPlugins) { Set<GrailsPlugin> observers = pluginToObserverMap.get(observedPlugin); if (observers == null) { observers = new HashSet<GrailsPlugin>(); pluginToObserverMap.put(observedPlugin, observers); } observers.add(plugin); } pluginList.add(plugin); plugins.put(plugin.getName(), plugin); classNameToPluginMap.put(plugin.getPluginClass().getName(), plugin); } protected boolean canRegisterPlugin(GrailsPlugin plugin) { Environment environment = Environment.getCurrent(); return plugin.isEnabled() && plugin.supportsEnvironment(environment); } protected void evictPlugin(GrailsPlugin evictor, String evicteeName) { GrailsPlugin pluginToEvict = plugins.get(evicteeName); if (pluginToEvict != null) { pluginList.remove(pluginToEvict); plugins.remove(pluginToEvict.getName()); if (LOG.isInfoEnabled()) { LOG.info("Grails plug-in " + pluginToEvict + " was evicted by " + evictor); } } } private boolean hasGrailsPlugin(String name, String version) { return getGrailsPlugin(name, version) != null; } @Override public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.applicationContext = applicationContext; for (GrailsPlugin plugin : pluginList) { plugin.setApplicationContext(applicationContext); } } public void setParentApplicationContext(ApplicationContext parent) { parentCtx = parent; } /** * @deprecated Replaced by agent-based reloading, will be removed in a future version of Grails */ @Deprecated public void checkForChanges() { // do nothing } public void reloadPlugin(GrailsPlugin plugin) { plugin.doArtefactConfiguration(); RuntimeSpringConfiguration springConfig = new DefaultRuntimeSpringConfiguration(parentCtx); doRuntimeConfiguration(plugin.getName(), springConfig); springConfig.registerBeansWithContext((GenericApplicationContext) applicationContext); plugin.doWithApplicationContext(applicationContext); plugin.doWithDynamicMethods(applicationContext); } @Override public void setApplication(GrailsApplication application) { Assert.notNull(application, "Argument [application] cannot be null"); this.application = application; for (GrailsPlugin plugin : pluginList) { plugin.setApplication(application); } } @Override public void doDynamicMethods() { checkInitialised(); // remove common meta classes just to be sure MetaClassRegistry registry = GroovySystem.getMetaClassRegistry(); for (Class<?> COMMON_CLASS : COMMON_CLASSES) { registry.removeMetaClass(COMMON_CLASS); } for (GrailsPlugin plugin : pluginList) { if (plugin.supportsCurrentScopeAndEnvironment()) { try { plugin.doWithDynamicMethods(applicationContext); } catch (Throwable t) { throw new GrailsConfigurationException( "Error configuring dynamic methods for plugin " + plugin + ": " + t.getMessage(), t); } } } } public void setPluginFilter(PluginFilter pluginFilter) { this.pluginFilter = pluginFilter; } private PluginFilter getPluginFilter() { if (pluginFilter == null) { pluginFilter = new IdentityPluginFilter(); } return pluginFilter; } List<GrailsPlugin> getPluginList() { return Collections.unmodifiableList(pluginList); } }