opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/shardstrategy/ShardStrategyFactory.java

   1 /*
   2  * Copyright (c) 2014 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.shardstrategy;
  10
  11 import com.google.common.base.Preconditions;
  12 import org.opendaylight.controller.cluster.datastore.config.Configuration;
  13 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  14 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  15 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  16
  17 public class ShardStrategyFactory {
  18     private static final String UNKNOWN_MODULE_NAME = "unknown";
  19
  20     private final Configuration configuration;
  21     private final LogicalDatastoreType logicalStoreType;
  22
  23     public ShardStrategyFactory(final Configuration configuration, final LogicalDatastoreType logicalStoreType) {
  24         Preconditions.checkState(configuration != null, "configuration should not be missing");
  25         this.configuration = configuration;
  26         this.logicalStoreType = Preconditions.checkNotNull(logicalStoreType);
  27     }
  28
  29     public ShardStrategy getStrategy(final YangInstanceIdentifier path) {
  30         Preconditions.checkNotNull(path, "path should not be null");
  31
  32         // try with the legacy module based shard mapping
  33         final String moduleName = getModuleName(path);
  34         final ShardStrategy shardStrategy = configuration.getStrategyForModule(moduleName);
  35         if (shardStrategy == null) {
  36             // retry with prefix based sharding
  37             final ShardStrategy strategyForPrefix =
  38                     configuration.getStrategyForPrefix(new DOMDataTreeIdentifier(logicalStoreType, path));
  39             if (strategyForPrefix == null) {
  40                 return DefaultShardStrategy.getInstance();
  41             }
  42             return strategyForPrefix;
  43         }
  44
  45         return shardStrategy;
  46     }
  47
  48     public static ShardStrategy newShardStrategyInstance(final String moduleName, final String strategyName,
  49             final Configuration configuration) {
  50         if (ModuleShardStrategy.NAME.equals(strategyName)) {
  51             return new ModuleShardStrategy(moduleName, configuration);
  52         }
  53
  54         return DefaultShardStrategy.getInstance();
  55     }
  56
  57     private String getModuleName(final YangInstanceIdentifier path) {
  58         if (path.isEmpty()) {
  59             return UNKNOWN_MODULE_NAME;
  60         }
  61
  62         String namespace = path.getPathArguments().get(0).getNodeType().getNamespace().toASCIIString();
  63         String moduleName = configuration.getModuleNameFromNameSpace(namespace);
  64         return moduleName != null ? moduleName : UNKNOWN_MODULE_NAME;
  65     }
  66 }