| /* |
| * 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.capabilities.oakdescriptors; |
| |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.regex.Pattern; |
| |
| import javax.jcr.RepositoryException; |
| import javax.jcr.ValueFormatException; |
| |
| import org.apache.sling.capabilities.CapabilitiesSource; |
| import org.apache.sling.jcr.api.SlingRepository; |
| import org.osgi.service.component.ComponentContext; |
| import org.osgi.service.component.annotations.Activate; |
| import org.osgi.service.component.annotations.Component; |
| import org.osgi.service.component.annotations.Reference; |
| import org.osgi.service.metatype.annotations.AttributeDefinition; |
| import org.osgi.service.metatype.annotations.Designate; |
| import org.osgi.service.metatype.annotations.ObjectClassDefinition; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** CapabilitiesSource that provides information on the Oak |
| * by exposing (some) repository descriptor values */ |
| @Component(service = CapabilitiesSource.class) |
| @Designate(ocd = OakDescriptorSource.Config.class) |
| public class OakDescriptorSource implements CapabilitiesSource { |
| |
| public static final String NAMESPACE = "org.apache.sling.oak.descriptor"; |
| |
| private final Logger log = LoggerFactory.getLogger(getClass().getName()); |
| |
| @Reference |
| private SlingRepository repository; |
| |
| private int cacheLifetimeSeconds; |
| |
| private long cacheExpires; |
| |
| private Map<String, Object> cachedReadOnlyMap; |
| |
| private Pattern[] keyPatterns; |
| |
| @ObjectClassDefinition(name = "Apache Sling Capabilities - Oak Descriptors Source", description = "Provides information about Oak by exposing Oak Repository Descriptors") |
| public static @interface Config { |
| @AttributeDefinition(name = "Key Whitelist", description = "List of Oak Repository Descriptor keys that are exposed.") |
| String[] keyWhitelist() default { "" }; |
| |
| @AttributeDefinition(name = "Cache time-to-live in seconds", description = "The repository descriptor values are cached for this amount of time, " |
| + "accounting for potentially expensive value calculations") |
| int cacheLifetimeSeconds() default 60; |
| } |
| |
| @Activate |
| protected void activate(Config cfg, ComponentContext ctx) { |
| cacheLifetimeSeconds = cfg.cacheLifetimeSeconds(); |
| if (cfg.keyWhitelist() == null || cfg.keyWhitelist().length == 0) { |
| keyPatterns = null; |
| } else { |
| keyPatterns = new Pattern[cfg.keyWhitelist().length]; |
| int i = 0; |
| for (String regex : cfg.keyWhitelist()) { |
| keyPatterns[i++] = Pattern.compile(regex); |
| } |
| } |
| } |
| |
| @Override |
| public Map<String, Object> getCapabilities() throws Exception { |
| final SlingRepository localRepo = repository; |
| if (localRepo == null) { |
| return Collections.emptyMap(); |
| } |
| |
| refreshCachedValues(); |
| return cachedReadOnlyMap; |
| } |
| |
| private void refreshCachedValues() { |
| if (System.currentTimeMillis() < cacheExpires) { |
| log.debug("refreshCachedValues: Using cached oak repository descriptor value"); |
| return; |
| } |
| |
| cacheExpires = System.currentTimeMillis() + (cacheLifetimeSeconds * 1000L); |
| |
| String[] keys = repository.getDescriptorKeys(); |
| List<String> filteredKeys = filterKeys(keys); |
| if (filteredKeys == null || filteredKeys.isEmpty()) { |
| cachedReadOnlyMap = Collections.emptyMap(); |
| } |
| |
| final HashMap<String, Object> result = new HashMap<>(); |
| for (String key : filteredKeys) { |
| try { |
| result.put(key, repository.getDescriptorValue(key).getString()); |
| } catch (ValueFormatException e) { |
| log.debug("refreshCachedValues: ValueFormatException ({}) reading key ({})", e.getMessage(), key); |
| } catch (IllegalStateException e) { |
| log.debug("refreshCachedValues: IllegalStateException ({}) reading key ({})", e.getMessage(), key); |
| } catch (RepositoryException e) { |
| log.debug("refreshCachedValues: RepositoryException ({}) reading key ({})", e.getMessage(), key); |
| } |
| } |
| cachedReadOnlyMap = Collections.unmodifiableMap(result); |
| |
| log.debug("refreshCachedValues: refreshed oak repository descriptor values"); |
| |
| } |
| |
| private List<String> filterKeys(String[] keys) { |
| final List<String> result = new LinkedList<>(); |
| for (String key : keys) { |
| if (whitelisted(key)) { |
| result.add(key); |
| } |
| } |
| return result; |
| } |
| |
| private boolean whitelisted(String key) { |
| if (keyPatterns == null || keyPatterns.length == 0) { |
| // nothing white-listed |
| return false; |
| } |
| if (key == null || key.length() == 0) { |
| // empty key is not allowed |
| return false; |
| } |
| for (Pattern keyPattern : keyPatterns) { |
| if (matches(key, keyPattern)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| private boolean matches(String key, Pattern keyPattern) { |
| if (keyPattern == null) { |
| return false; |
| } |
| return keyPattern.matcher(key).matches(); |
| } |
| |
| @Override |
| public String getNamespace() { |
| return NAMESPACE; |
| } |
| |
| } |