com.adobe.acs.commons.httpcache.invalidator.event.JCRNodeChangeEventHandler Maven / Gradle / Ivy
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* ACS AEM Commons Bundle
* %%
* Copyright (C) 2015 Adobe
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* 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
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package com.adobe.acs.commons.httpcache.invalidator.event;
import java.util.Collections;
import java.util.Dictionary;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import org.apache.felix.scr.annotations.Activate;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.ConfigurationPolicy;
import org.apache.felix.scr.annotations.Deactivate;
import org.apache.felix.scr.annotations.Properties;
import org.apache.felix.scr.annotations.Property;
import org.apache.felix.scr.annotations.Reference;
import org.apache.sling.api.SlingConstants;
import org.apache.sling.api.resource.observation.ExternalResourceChangeListener;
import org.apache.sling.api.resource.observation.ResourceChange;
import org.apache.sling.api.resource.observation.ResourceChangeListener;
import org.apache.sling.commons.osgi.PropertiesUtil;
import org.apache.sling.event.jobs.JobManager;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;
import org.osgi.service.event.Event;
import org.osgi.service.event.EventConstants;
import org.osgi.service.event.EventHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.adobe.acs.commons.httpcache.invalidator.CacheInvalidationJobConstants;
/**
* Sample http cache invalidation job creator. Creates invalidation job when there is a change in JCR repository. Cache
* invalidation events could be sling event handlers, sling filter to trap replication events, workflow steps, etc.
* Invalidation event creates and starts Invalidation jobs. This is modeled as a sling observer which listens
* to any change in paths (by default) -- /content, /etc and creates an invalidation job. The intention of this
* invalidation job is that whenever there is any change in the above said paths, the configured cache needs to be
* invalidated.
*/
// @formatter:off
@Component(label = "ACS AEM Commons - HTTP Cache - JCR node change invalidator",
description = "Watches for the configured JCR paths and triggers cache invalidation job.",
metatype = true,
policy = ConfigurationPolicy.REQUIRE)
@Properties({
@Property(label = "JCR paths to watch for changes. (legacy)",
description = "Paths expressed in LDAP syntax. Example: (|(path=/content*)(path=/etc*))"
+ " - Watches for changes under /content or /etc. This is deprecated - consider "
+ "using " + ResourceChangeListener.PATHS + " instead for better performance.",
name = EventConstants.EVENT_FILTER),
@Property(label = "JCR paths to watch for changes.",
value = {"/content", "/etc"},
description = "List of paths to watch. Entries with the 'glob:' prefix are interpreted as globs, "
+ "i.e. the * and ** wildcards are supported.",
name = ResourceChangeListener.PATHS),
@Property(label = "Type of change to listen to",
value = {"ADDED", "REMOVED","CHANGED"},
name = ResourceChangeListener.CHANGES),
@Property(name = "webconsole.configurationFactory.nameHint",
value = "JCR paths to watch for changes: {" + EventConstants.EVENT_FILTER + "} "
+ "{" + ResourceChangeListener.PATHS + "}",
propertyPrivate = true)
})
// We do _not_ register as a service. We register ourselves manually as either an EventHandler or
// a ResourceChangeListener based on what config we have.
// @formatter:on
public class JCRNodeChangeEventHandler implements EventHandler, ResourceChangeListener, ExternalResourceChangeListener {
private static final Logger log = LoggerFactory.getLogger(JCRNodeChangeEventHandler.class);
@Reference
private JobManager jobManager;
private ServiceRegistration registration;
@Activate
@SuppressWarnings({"squid:S1149","deprecation"})
protected void activate(BundleContext context, Map config) {
String pathFilter = PropertiesUtil.toString(config.get(EventConstants.EVENT_FILTER), "");
if (!pathFilter.isEmpty()) {
log.warn("LDAP-style path filter detected, so a legacy event-based listener will be registered. "
+ "Consider using a list of paths instead to improve performance.");
Dictionary properties = new Hashtable<>();
properties.put(EventConstants.EVENT_TOPIC, new String[] { SlingConstants.TOPIC_RESOURCE_CHANGED,
SlingConstants.TOPIC_RESOURCE_ADDED, SlingConstants.TOPIC_RESOURCE_REMOVED });
properties.put(EventConstants.EVENT_FILTER, pathFilter);
registration = context.registerService(EventHandler.class, this, properties);
} else {
Dictionary properties = new Hashtable<>();
properties.put(ResourceChangeListener.PATHS, config.get(ResourceChangeListener.PATHS));
properties.put(ResourceChangeListener.CHANGES, config.get(ResourceChangeListener.CHANGES));
registration = context.registerService(ResourceChangeListener.class, this, properties);
}
}
@Deactivate
protected void deactivate() {
registration.unregister();
}
@Override
public void handleEvent(final Event event) {
// Get the required information from the event.
final String path = (String) event.getProperty(SlingConstants.PROPERTY_PATH);
handlePath(path);
}
@Override
public void onChange(List changes) {
for (ResourceChange change : changes) {
handlePath(change.getPath());
}
}
private void handlePath(String path) {
final Map payload = Collections.singletonMap(CacheInvalidationJobConstants.PAYLOAD_KEY_DATA_CHANGE_PATH, path);
jobManager.addJob(CacheInvalidationJobConstants.TOPIC_HTTP_CACHE_INVALIDATION_JOB, payload);
log.debug("New invalidation job created with the payload path. - {}", path);
}
}