opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/entityownership/selectionstrategy/EntityOwnerSelectionStrategyConfigReader.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy;
  10
  11 import com.google.common.base.Preconditions;
  12 import java.io.IOException;
  13 import java.util.Dictionary;
  14 import java.util.Enumeration;
  15 import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.EntityOwnerSelectionStrategyConfig.Builder;
  16 import org.osgi.framework.BundleContext;
  17 import org.osgi.framework.ServiceReference;
  18 import org.osgi.service.cm.Configuration;
  19 import org.osgi.service.cm.ConfigurationAdmin;
  20 import org.slf4j.Logger;
  21 import org.slf4j.LoggerFactory;
  22
  23 /**
  24  * Reads the entity owner selection strategy config.
  25  *
  26  * @deprecated FIXME: Service injection class. This class needs to be eliminated in favor of proper service injection,
  27  *             which can be any of OSGi (which this class uses internally), java.util.ServiceLoader, or config
  28  *             subsystem.
  29  */
  30 @Deprecated
  31 public final class EntityOwnerSelectionStrategyConfigReader {
  32     public static final String CONFIG_ID = "org.opendaylight.controller.cluster.entity.owner.selection.strategies";
  33
  34     private static final Logger LOG = LoggerFactory.getLogger(EntityOwnerSelectionStrategyConfigReader.class);
  35     private static final String ENTITY_TYPE_PREFIX = "entity.type.";
  36
  37     private EntityOwnerSelectionStrategyConfigReader() {
  38         // Hidden on purpose
  39     }
  40
  41     @SuppressWarnings("checkstyle:IllegalCatch")
  42     public static EntityOwnerSelectionStrategyConfig loadStrategyWithConfig(final BundleContext bundleContext) {
  43         final EntityOwnerSelectionStrategyConfig.Builder builder = EntityOwnerSelectionStrategyConfig.newBuilder();
  44
  45         final ServiceReference<ConfigurationAdmin> configAdminServiceReference =
  46                 bundleContext.getServiceReference(ConfigurationAdmin.class);
  47         if (configAdminServiceReference == null) {
  48             LOG.warn("No ConfigurationAdmin service found");
  49             return builder.build();
  50         }
  51
  52         final ConfigurationAdmin configAdmin = bundleContext.getService(configAdminServiceReference);
  53         if (configAdmin == null) {
  54             LOG.warn("Failed to get ConfigurationAdmin service");
  55             return builder.build();
  56         }
  57
  58         final Configuration config;
  59         try {
  60             config = configAdmin.getConfiguration(CONFIG_ID);
  61             if (config != null) {
  62                 return parseConfiguration(builder, config);
  63             }
  64
  65             LOG.debug("Could not read strategy configuration file, will use default configuration");
  66         } catch (IOException e1) {
  67             LOG.warn("Failed to get configuration for {}, starting up empty", CONFIG_ID, e1);
  68             return builder.build();
  69         } finally {
  70             try {
  71                 bundleContext.ungetService(configAdminServiceReference);
  72             } catch (Exception e) {
  73                 LOG.debug("Error from ungetService", e);
  74             }
  75         }
  76
  77         return builder.build();
  78     }
  79
  80     private static EntityOwnerSelectionStrategyConfig parseConfiguration(final Builder builder,
  81             final Configuration config) {
  82         // Historic note: java.util.Dictionary since introduction of java.util.Map in Java 1.2
  83         final Dictionary<String, Object> properties = config.getProperties();
  84         if (properties == null) {
  85             LOG.debug("Empty strategy configuration {}, using defaults", config);
  86             return builder.build();
  87         }
  88
  89         // No java.util.Iterable: Wheeey, pre-Java 5 world!!!
  90         final Enumeration<String> keys = properties.keys();
  91         while (keys.hasMoreElements()) {
  92             final String key = keys.nextElement();
  93             if (!key.startsWith(ENTITY_TYPE_PREFIX)) {
  94                 LOG.debug("Ignoring non-conforming property key : {}");
  95                 continue;
  96             }
  97
  98             final String[] strategyClassAndDelay = ((String) properties.get(key)).split(",");
  99             final Class<? extends EntityOwnerSelectionStrategy> aClass;
 100             try {
 101                 aClass = loadClass(strategyClassAndDelay[0]);
 102             } catch (ClassNotFoundException e) {
 103                 LOG.error("Failed to load class {}, ignoring it", strategyClassAndDelay[0], e);
 104                 continue;
 105             }
 106
 107             final long delay;
 108             if (strategyClassAndDelay.length > 1) {
 109                 delay = Long.parseLong(strategyClassAndDelay[1]);
 110             } else {
 111                 delay = 0;
 112             }
 113
 114             String entityType = key.substring(key.lastIndexOf(".") + 1);
 115             builder.addStrategy(entityType, aClass, delay);
 116             LOG.debug("Entity Type '{}' using strategy {} delay {}", entityType, aClass, delay);
 117         }
 118
 119         return builder.build();
 120     }
 121
 122     @Deprecated
 123     @SuppressWarnings("unchecked")
 124     private static Class<? extends EntityOwnerSelectionStrategy> loadClass(final String strategyClassAndDelay)
 125             throws ClassNotFoundException {
 126         final Class<?> clazz;
 127         try {
 128             clazz = EntityOwnerSelectionStrategyConfigReader.class.getClassLoader().loadClass(strategyClassAndDelay);
 129         } catch (ClassNotFoundException e) {
 130             throw new IllegalArgumentException("Failed to load strategy " + strategyClassAndDelay, e);
 131         }
 132
 133         Preconditions.checkArgument(EntityOwnerSelectionStrategy.class.isAssignableFrom(clazz),
 134             "Selected implementation %s must implement EntityOwnerSelectionStrategy, clazz");
 135
 136         return (Class<? extends EntityOwnerSelectionStrategy>) clazz;
 137     }
 138 }