src/main/java/org/apache/sling/startupfilter/impl/StartupFilterImpl.java - sling-org-apache-sling-startupfilter - Git at Google

 /*
  * 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.sling.startupfilter.impl;

 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Hashtable;
 import java.util.List;
 import java.util.Map;

 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Property;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.ReferencePolicy;
 import org.apache.felix.scr.annotations.Service;
 import org.apache.sling.startupfilter.StartupFilter;
 import org.apache.sling.startupfilter.StartupFilterDisabler;
 import org.apache.sling.startupfilter.StartupInfoProvider;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.Constants;
 import org.osgi.framework.ServiceReference;
 import org.osgi.framework.ServiceRegistration;
 import org.osgi.service.http.whiteboard.HttpWhiteboardConstants;
 import org.osgi.util.tracker.ServiceTracker;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 /** StartupFilter implementation. Initially registered
  *  as a StartupFilter only, the Filter registration
  *  is dynamic, on-demand. */
 @Component(immediate=true, metatype=true)
 @Service(value=StartupFilter.class)
 public class StartupFilterImpl implements StartupFilter, Filter {

     private final Logger log = LoggerFactory.getLogger(getClass());
     private ServiceRegistration<Filter> filterServiceRegistration;
     private BundleContext bundleContext;
     private ServiceTracker<StartupInfoProvider, StartupInfoProvider> providersTracker;
     private int providersTrackerCount = -1;

     private final List<StartupInfoProvider> providers = new ArrayList<StartupInfoProvider>();

     @Property(boolValue=true)
     public static final String ACTIVE_BY_DEFAULT_PROP = "active.by.default";
     private boolean defaultFilterActive;

     public static final String DEFAULT_MESSAGE = "Startup in progress";

     @Property(value=DEFAULT_MESSAGE)
     public static final String DEFAULT_MESSAGE_PROP = "default.message";
     private String defaultMessage;

     @Reference(cardinality=ReferenceCardinality.OPTIONAL_UNARY, policy=ReferencePolicy.DYNAMIC)
     private volatile StartupFilterDisabler startupFilterDisabler;

     private static final String FRAMEWORK_PROP_MANAGER_ROOT = "felix.webconsole.manager.root";
     static final String DEFAULT_MANAGER_ROOT = "/system/console";
     private String managerRoot;

     /** @inheritDoc */
     @Override
     public void doFilter(ServletRequest request, ServletResponse sr, FilterChain chain) throws IOException, ServletException {

         // Disable if a StartupFilterDisabler is present
         if(startupFilterDisabler!= null) {
             log.info("StartupFilterDisabler service present, disabling StartupFilter ({})",
                     startupFilterDisabler.getReason());
             disable();
             chain.doFilter(request, sr);
             return;
         }

         // Bypass for the managerRoot path
         if(request instanceof HttpServletRequest) {
             final String pathInfo = ((HttpServletRequest)request).getPathInfo();
             if(managerRoot != null && managerRoot.length() > 0 && pathInfo.startsWith(managerRoot)) {
                 log.debug("Bypassing filter for path {} which starts with {}", pathInfo, managerRoot);
                 chain.doFilter(request, sr);
                 return;
             }
         }

         updateProviders();

         final StringBuilder sb = new StringBuilder();
         sb.append(defaultMessage);
         for(StartupInfoProvider p : providers) {
             sb.append('\n');
             sb.append(p.getProgressInfo());
         }

         // Do not use setError to avoid triggering the container's error page,
         // as that might cascade other errors during startup
         final HttpServletResponse response = (HttpServletResponse)sr;
         response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
         response.setContentType("text/plain");
         response.setCharacterEncoding("UTF-8");
         response.getWriter().write(sb.toString());
         response.getWriter().flush();
     }

     @Override
     public String toString() {
         return getClass().getSimpleName() + ": " + (isEnabled() ? "enabled" : "disabled");
     }

     /** @inheritDoc */
     @Override
     public void destroy() {
     }

     /** @inheritDoc */
     @Override
     public void init(FilterConfig cfg) throws ServletException {
     }

     /** If needed, update our list of providers */
     private void updateProviders() {
         if(providersTracker.getTrackingCount() != providersTrackerCount) {
             synchronized(this) {
                 if(providersTracker.getTrackingCount() != providersTrackerCount) {
                     providers.clear();
                     final ServiceReference<StartupInfoProvider> [] refs = providersTracker.getServiceReferences();
                     if(refs != null) {
                         for(ServiceReference<StartupInfoProvider> ref : refs) {
                             providers.add(bundleContext.getService(ref));
                         }
                     }
                 }
                 providersTrackerCount = providersTracker.getTrackingCount();
                 log.info("Reloaded list of StartupInfoProvider: {}", providers);
             }
         }
     }

     @Activate
     protected void activate(final BundleContext ctx, final Map<String, Object> properties) throws InterruptedException {
         bundleContext = ctx;

         providersTracker = new ServiceTracker(bundleContext, StartupInfoProvider.class, null);
         providersTracker.open();

         Object prop = properties.get(DEFAULT_MESSAGE_PROP);
         defaultMessage = prop == null ? DEFAULT_MESSAGE : prop.toString();

         prop = properties.get(ACTIVE_BY_DEFAULT_PROP);
         defaultFilterActive = (prop instanceof Boolean ? (Boolean)prop : false);

         prop = bundleContext.getProperty(FRAMEWORK_PROP_MANAGER_ROOT);
         managerRoot = prop == null ? DEFAULT_MANAGER_ROOT : prop.toString();

         if(defaultFilterActive) {
             enable();
         }
         log.info("Activated, enabled={}, managerRoot={}", isEnabled(), managerRoot);
     }

     @Deactivate
     protected void deactivate() throws InterruptedException {
         disable();
         providersTracker.close();
         providersTracker = null;
         bundleContext = null;
     }


     @Override
     public synchronized void enable() {
         if (filterServiceRegistration == null) {
             final String pattern = "/";
             final Hashtable<String, Object> params = new Hashtable<String, Object>();
             params.put(Constants.SERVICE_RANKING, 0x9000); // run before RequestLoggerFilter (0x8000)
             params.put("sling.filter.scope", "REQUEST");
             params.put(HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_SELECT,
                     "(" + HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_NAME + "=*)");
             params.put(HttpWhiteboardConstants.HTTP_WHITEBOARD_FILTER_PATTERN, pattern);
             filterServiceRegistration = bundleContext.registerService(Filter.class, this, params);
             log.info("Registered {} as a servlet filter service with pattern {}", this, pattern);
         }
     }

     @Override
     public synchronized void disable() {
         if (filterServiceRegistration != null) {
             filterServiceRegistration.unregister();
             filterServiceRegistration = null;
             log.info("Filter service disabled");
         }
     }

     @Override
     public synchronized boolean isEnabled() {
         return filterServiceRegistration != null;
     }
 }
	/*
	* 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.sling.startupfilter.impl;

	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.Hashtable;
	import java.util.List;
	import java.util.Map;

	import javax.servlet.Filter;
	import javax.servlet.FilterChain;
	import javax.servlet.FilterConfig;
	import javax.servlet.ServletException;
	import javax.servlet.ServletRequest;
	import javax.servlet.ServletResponse;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;

	import org.apache.felix.scr.annotations.Activate;
	import org.apache.felix.scr.annotations.Component;
	import org.apache.felix.scr.annotations.Deactivate;
	import org.apache.felix.scr.annotations.Property;
	import org.apache.felix.scr.annotations.Reference;
	import org.apache.felix.scr.annotations.ReferenceCardinality;
	import org.apache.felix.scr.annotations.ReferencePolicy;
	import org.apache.felix.scr.annotations.Service;
	import org.apache.sling.startupfilter.StartupFilter;
	import org.apache.sling.startupfilter.StartupFilterDisabler;
	import org.apache.sling.startupfilter.StartupInfoProvider;
	import org.osgi.framework.BundleContext;
	import org.osgi.framework.Constants;
	import org.osgi.framework.ServiceReference;
	import org.osgi.framework.ServiceRegistration;
	import org.osgi.service.http.whiteboard.HttpWhiteboardConstants;
	import org.osgi.util.tracker.ServiceTracker;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	/** StartupFilter implementation. Initially registered
	* as a StartupFilter only, the Filter registration
	* is dynamic, on-demand. */
	@Component(immediate=true, metatype=true)
	@Service(value=StartupFilter.class)
	public class StartupFilterImpl implements StartupFilter, Filter {

	private final Logger log = LoggerFactory.getLogger(getClass());
	private ServiceRegistration<Filter> filterServiceRegistration;
	private BundleContext bundleContext;
	private ServiceTracker<StartupInfoProvider, StartupInfoProvider> providersTracker;
	private int providersTrackerCount = -1;

	private final List<StartupInfoProvider> providers = new ArrayList<StartupInfoProvider>();

	@Property(boolValue=true)
	public static final String ACTIVE_BY_DEFAULT_PROP = "active.by.default";
	private boolean defaultFilterActive;

	public static final String DEFAULT_MESSAGE = "Startup in progress";

	@Property(value=DEFAULT_MESSAGE)
	public static final String DEFAULT_MESSAGE_PROP = "default.message";
	private String defaultMessage;

	@Reference(cardinality=ReferenceCardinality.OPTIONAL_UNARY, policy=ReferencePolicy.DYNAMIC)
	private volatile StartupFilterDisabler startupFilterDisabler;

	private static final String FRAMEWORK_PROP_MANAGER_ROOT = "felix.webconsole.manager.root";
	static final String DEFAULT_MANAGER_ROOT = "/system/console";
	private String managerRoot;

	/** @inheritDoc */
	@Override
	public void doFilter(ServletRequest request, ServletResponse sr, FilterChain chain) throws IOException, ServletException {

	// Disable if a StartupFilterDisabler is present
	if(startupFilterDisabler!= null) {
	log.info("StartupFilterDisabler service present, disabling StartupFilter ({})",
	startupFilterDisabler.getReason());
	disable();
	chain.doFilter(request, sr);
	return;
	}

	// Bypass for the managerRoot path
	if(request instanceof HttpServletRequest) {
	final String pathInfo = ((HttpServletRequest)request).getPathInfo();
	if(managerRoot != null && managerRoot.length() > 0 && pathInfo.startsWith(managerRoot)) {
	log.debug("Bypassing filter for path {} which starts with {}", pathInfo, managerRoot);
	chain.doFilter(request, sr);
	return;
	}
	}

	updateProviders();

	final StringBuilder sb = new StringBuilder();
	sb.append(defaultMessage);
	for(StartupInfoProvider p : providers) {
	sb.append('\n');
	sb.append(p.getProgressInfo());
	}

	// Do not use setError to avoid triggering the container's error page,
	// as that might cascade other errors during startup
	final HttpServletResponse response = (HttpServletResponse)sr;
	response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
	response.setContentType("text/plain");
	response.setCharacterEncoding("UTF-8");
	response.getWriter().write(sb.toString());
	response.getWriter().flush();
	}

	@Override
	public String toString() {
	return getClass().getSimpleName() + ": " + (isEnabled() ? "enabled" : "disabled");
	}

	/** @inheritDoc */
	@Override
	public void destroy() {
	}

	/** @inheritDoc */
	@Override
	public void init(FilterConfig cfg) throws ServletException {
	}

	/** If needed, update our list of providers */
	private void updateProviders() {
	if(providersTracker.getTrackingCount() != providersTrackerCount) {
	synchronized(this) {
	if(providersTracker.getTrackingCount() != providersTrackerCount) {
	providers.clear();
	final ServiceReference<StartupInfoProvider> [] refs = providersTracker.getServiceReferences();
	if(refs != null) {
	for(ServiceReference<StartupInfoProvider> ref : refs) {
	providers.add(bundleContext.getService(ref));
	}
	}
	}
	providersTrackerCount = providersTracker.getTrackingCount();
	log.info("Reloaded list of StartupInfoProvider: {}", providers);
	}
	}
	}

	@Activate
	protected void activate(final BundleContext ctx, final Map<String, Object> properties) throws InterruptedException {
	bundleContext = ctx;

	providersTracker = new ServiceTracker(bundleContext, StartupInfoProvider.class, null);
	providersTracker.open();

	Object prop = properties.get(DEFAULT_MESSAGE_PROP);
	defaultMessage = prop == null ? DEFAULT_MESSAGE : prop.toString();

	prop = properties.get(ACTIVE_BY_DEFAULT_PROP);
	defaultFilterActive = (prop instanceof Boolean ? (Boolean)prop : false);

	prop = bundleContext.getProperty(FRAMEWORK_PROP_MANAGER_ROOT);
	managerRoot = prop == null ? DEFAULT_MANAGER_ROOT : prop.toString();

	if(defaultFilterActive) {
	enable();
	}
	log.info("Activated, enabled={}, managerRoot={}", isEnabled(), managerRoot);
	}

	@Deactivate
	protected void deactivate() throws InterruptedException {
	disable();
	providersTracker.close();
	providersTracker = null;
	bundleContext = null;
	}


	@Override
	public synchronized void enable() {
	if (filterServiceRegistration == null) {
	final String pattern = "/";
	final Hashtable<String, Object> params = new Hashtable<String, Object>();
	params.put(Constants.SERVICE_RANKING, 0x9000); // run before RequestLoggerFilter (0x8000)
	params.put("sling.filter.scope", "REQUEST");
	params.put(HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_SELECT,
	"(" + HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_NAME + "=*)");
	params.put(HttpWhiteboardConstants.HTTP_WHITEBOARD_FILTER_PATTERN, pattern);
	filterServiceRegistration = bundleContext.registerService(Filter.class, this, params);
	log.info("Registered {} as a servlet filter service with pattern {}", this, pattern);
	}
	}

	@Override
	public synchronized void disable() {
	if (filterServiceRegistration != null) {
	filterServiceRegistration.unregister();
	filterServiceRegistration = null;
	log.info("Filter service disabled");
	}
	}

	@Override
	public synchronized boolean isEnabled() {
	return filterServiceRegistration != null;
	}
	}