Add examples for reading HBase and Cassandra InputFormats from Python

examples/src/main/python/cassandra_inputformat.py

@@ -0,0 +1,79 @@
+#
+# 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.
+#
+
+import sys
+
+from pyspark import SparkContext
+
+"""
+Create data in Cassandra fist
+(following: https://wiki.apache.org/cassandra/GettingStarted)
+
+cqlsh> CREATE KEYSPACE test
+   ... WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 };
+cqlsh> use test;
+cqlsh:test> CREATE TABLE users (
+        ...   user_id int PRIMARY KEY,
+        ...   fname text,
+        ...   lname text
+        ... );
+cqlsh:test> INSERT INTO users (user_id,  fname, lname)
+        ...   VALUES (1745, 'john', 'smith');
+cqlsh:test> INSERT INTO users (user_id,  fname, lname)
+        ...   VALUES (1744, 'john', 'doe');
+cqlsh:test> INSERT INTO users (user_id,  fname, lname)
+        ...   VALUES (1746, 'john', 'smith');
+cqlsh:test> SELECT * FROM users;
+
+ user_id | fname | lname
+---------+-------+-------
+    1745 |  john | smith
+    1744 |  john |   doe
+    1746 |  john | smith
+"""
+if __name__ == "__main__":
+    if len(sys.argv) != 4:
+        print >> sys.stderr, """
+        Usage: cassandra_inputformat <host> <keyspace> <cf>
+
+        Run with example jar:
+        ./bin/spark-submit --driver-class-path /path/to/example/jar /path/to/examples/cassandra_inputformat.py <host> <keyspace> <cf>
+        Assumes you have some data in Cassandra already, running on <host>, in <keyspace> and <cf>
+        """
+        exit(-1)
+
+    host = sys.argv[1]
+    keyspace = sys.argv[2]
+    cf = sys.argv[3]
+    sc = SparkContext(appName="HBaseInputFormat")
+
+    conf = {"cassandra.input.thrift.address":host,
+            "cassandra.input.thrift.port":"9160",
+            "cassandra.input.keyspace":keyspace,
+            "cassandra.input.columnfamily":cf,
+            "cassandra.input.partitioner.class":"Murmur3Partitioner",
+            "cassandra.input.page.row.size":"3"}
+    cass_rdd = sc.newAPIHadoopRDD(
+        "org.apache.cassandra.hadoop.cql3.CqlPagingInputFormat",
+        "java.util.Map",
+        "java.util.Map",
+        keyConverter="org.apache.spark.examples.CassandraCQLKeyConverter",
+        valueConverter="org.apache.spark.examples.CassandraCQLValueConverter",
+        conf=conf)
+    output = cass_rdd.collect()
+    for (k, v) in output:
+        print (k, v)

examples/src/main/python/hbase_inputformat.py

@@ -0,0 +1,71 @@
+#
+# 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.
+#
+
+import sys
+
+from pyspark import SparkContext
+
+"""
+Create test data in HBase first:
+
+hbase(main):016:0> create 'test', 'f1'
+0 row(s) in 1.0430 seconds
+
+hbase(main):017:0> put 'test', 'row1', 'f1', 'value1'
+0 row(s) in 0.0130 seconds
+
+hbase(main):018:0> put 'test', 'row2', 'f1', 'value2'
+0 row(s) in 0.0030 seconds
+
+hbase(main):019:0> put 'test', 'row3', 'f1', 'value3'
+0 row(s) in 0.0050 seconds
+
+hbase(main):020:0> put 'test', 'row4', 'f1', 'value4'
+0 row(s) in 0.0110 seconds
+
+hbase(main):021:0> scan 'test'
+ROW                           COLUMN+CELL
+ row1                         column=f1:, timestamp=1401883411986, value=value1
+ row2                         column=f1:, timestamp=1401883415212, value=value2
+ row3                         column=f1:, timestamp=1401883417858, value=value3
+ row4                         column=f1:, timestamp=1401883420805, value=value4
+4 row(s) in 0.0240 seconds
+"""
+if __name__ == "__main__":
+    if len(sys.argv) != 3:
+        print >> sys.stderr, """
+        Usage: hbase_inputformat <host> <table>
+
+        Run with example jar:
+        ./bin/spark-submit --driver-class-path /path/to/example/jar /path/to/examples/hbase_inputformat.py <host> <table>
+        Assumes you have some data in HBase already, running on <host>, in <table>
+        """
+        exit(-1)
+
+    host = sys.argv[1]
+    table = sys.argv[2]
+    sc = SparkContext(appName="HBaseInputFormat")
+
+    conf = {"hbase.zookeeper.quorum": host, "hbase.mapreduce.inputtable": table}
+    hbase_rdd = sc.newAPIHadoopRDD("org.apache.hadoop.hbase.mapreduce.TableInputFormat",
+                                   "org.apache.hadoop.hbase.io.ImmutableBytesWritable",
+                                   "org.apache.hadoop.hbase.client.Result",
+                                   valueConverter="org.apache.spark.examples.HBaseConverter",
+                                   conf=conf)
+    output = hbase_rdd.collect()
+    for (k, v) in output:
+        print (k, v)

examples/src/main/scala/org/apache/spark/examples/CassandraCQLTest.scala

@@ -32,6 +32,23 @@ import org.apache.hadoop.mapreduce.Job
 
 import org.apache.spark.{SparkConf, SparkContext}
 import org.apache.spark.SparkContext._
+import org.apache.spark.api.python.Converter
+
+class CassandraCQLKeyConverter extends Converter {
+  import collection.JavaConversions._
+  override def convert(obj: Any) = {
+    val result = obj.asInstanceOf[java.util.Map[String, ByteBuffer]]
+    mapAsJavaMap(result.mapValues(bb => ByteBufferUtil.toInt(bb)))
+  }
+}
+
+class CassandraCQLValueConverter extends Converter {
+  import collection.JavaConversions._
+  override def convert(obj: Any) = {
+    val result = obj.asInstanceOf[java.util.Map[String, ByteBuffer]]
+    mapAsJavaMap(result.mapValues(bb => ByteBufferUtil.string(bb)))
+  }
+}
 
 /*
   Need to create following keyspace and column family in cassandra before running this example

examples/src/main/scala/org/apache/spark/examples/HBaseTest.scala

@@ -17,12 +17,21 @@
 
 package org.apache.spark.examples
 
-import org.apache.hadoop.hbase.client.HBaseAdmin
+import org.apache.hadoop.hbase.client.{Result, HBaseAdmin}
 import org.apache.hadoop.hbase.{HBaseConfiguration, HTableDescriptor}
 import org.apache.hadoop.hbase.mapreduce.TableInputFormat
 
 import org.apache.spark._
 import org.apache.spark.rdd.NewHadoopRDD
+import org.apache.spark.api.python.Converter
+import org.apache.hadoop.hbase.util.Bytes
+
+class HBaseConverter extends Converter {
+  override def convert(obj: Any) = {
+    val result = obj.asInstanceOf[Result]
+    Bytes.toStringBinary(result.value())
+  }
+}
 
 object HBaseTest {
   def main(args: Array[String]) {