Add hoodie-hive module to support hive registration of hoodie datasets

hoodie-hive/src/main/java/com/uber/hoodie/hive/PartitionStrategy.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2016 Uber Technologies, Inc. (hoodie-dev-group@uber.com)
+ *
+ * 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
+ * limitations under the License.
+ */
+
+package com.uber.hoodie.hive;
+
+import com.uber.hoodie.hive.client.HoodieFSClient;
+import com.uber.hoodie.hive.model.HoodieDatasetReference;
+import org.apache.hadoop.fs.FileStatus;
+import org.apache.hadoop.fs.Path;
+
+/**
+ * Abstraction to define HDFS partition strategies.
+ * Strategy provides hookups to map partitions on to physical layout
+ *
+ * @see SchemaStrategy
+ */
+public interface PartitionStrategy {
+    /**
+     * Scans the file system for all partitions and returns FileStatus[] which are the available partitions
+     *
+     * @param basePath
+     * @param fsClient
+     * @return
+     */
+    FileStatus[] scanAllPartitions(HoodieDatasetReference basePath, HoodieFSClient fsClient);
+
+    /**
+     * Get the list of hive field names the dataset will be partitioned on.
+     * The field name should be present in the storage schema.
+     *
+     * @return List of partitions field names
+     */
+    String[] getHivePartitionFieldNames();
+
+    /**
+     * Convert a Partition path (returned in scanAllPartitions) to values for column names returned in getHivePartitionFieldNames
+     * e.g. /data/topic/2016/12/12/ will return [2016, 12, 12]
+     *
+     * @param partition storage path
+     * @return List of partitions field values
+     */
+    String[] convertPartitionToValues(HoodieDatasetReference metadata, Path partition);
+}