stack/core/src/main/java/org/apache/usergrid/persistence/IndexBucketLocator.java

/*
 * 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.usergrid.persistence;


import java.util.List;
import java.util.UUID;


/**
 * Interface for locating different buckets for indexing entities. These buckets are not intended for user with time
 * series indexing. Rather this a means of partitioning index puts across multiple rows
 *
 * @author tnine
 */
public interface IndexBucketLocator {

    public enum IndexType {
        COLLECTION( "collection" ), CONNECTION( "connection" ), GEO( "geo" ), UNIQUE( "unique" );

        private final String type;


        private IndexType( String type ) {
            this.type = type;
        }


        public String getType() {
            return type;
        }

    }

    /**
     * Return the bucket to use for indexing this entity
     *
     * @param applicationId The application id
     * @param type The type of the index. This way indexing on the same property value for different types of indexes
     * does not cause collisions on partitioning and lookups
     * @param entityId The entity id to be indexed
     * @param components The strings and uniquely identify the path to this index. I.E entityType and propName,
     * collection name etc This string must remain the same for all reads and writes
     *
     * @return A bucket to use.  Note that ALL properties for the given entity should be in the same bucket.  This
     *         allows us to shard and execute queries in parallel.  Generally speaking, sharding on entityId is the best
     *         strategy, since this is an immutable value
     */
    public String getBucket( UUID applicationId, IndexType type, UUID entityId, String... components );

    /**
     * Get all buckets that exist for this application with the given entity type, and property name
     *
     * @param applicationId The application id
     * @param type The type of index
     * @param components The strings and uniquely identify the path to this index. I.E entityType and propName,
     * collection name etc
     *
     * @return All buckets for this application at the given component path
     */
    public List<String> getBuckets( UUID applicationId, IndexType type, String... components );
}