diff options
author | Davies Liu <davies@databricks.com> | 2015-02-02 19:16:27 -0800 |
---|---|---|
committer | Tathagata Das <tathagata.das1565@gmail.com> | 2015-02-02 19:16:27 -0800 |
commit | 0561c4544967fb853419f32e014fac9b8879b0db (patch) | |
tree | 54f64d9481de296bcb7676f82306896007b489b2 /python/pyspark | |
parent | 554403fd913685da879cf6a280c58a9fad19448a (diff) | |
download | spark-0561c4544967fb853419f32e014fac9b8879b0db.tar.gz spark-0561c4544967fb853419f32e014fac9b8879b0db.tar.bz2 spark-0561c4544967fb853419f32e014fac9b8879b0db.zip |
[SPARK-5154] [PySpark] [Streaming] Kafka streaming support in Python
This PR brings the Python API for Spark Streaming Kafka data source.
```
class KafkaUtils(__builtin__.object)
| Static methods defined here:
|
| createStream(ssc, zkQuorum, groupId, topics, storageLevel=StorageLevel(True, True, False, False,
2), keyDecoder=<function utf8_decoder>, valueDecoder=<function utf8_decoder>)
| Create an input stream that pulls messages from a Kafka Broker.
|
| :param ssc: StreamingContext object
| :param zkQuorum: Zookeeper quorum (hostname:port,hostname:port,..).
| :param groupId: The group id for this consumer.
| :param topics: Dict of (topic_name -> numPartitions) to consume.
| Each partition is consumed in its own thread.
| :param storageLevel: RDD storage level.
| :param keyDecoder: A function used to decode key
| :param valueDecoder: A function used to decode value
| :return: A DStream object
```
run the example:
```
bin/spark-submit --driver-class-path external/kafka-assembly/target/scala-*/spark-streaming-kafka-assembly-*.jar examples/src/main/python/streaming/kafka_wordcount.py localhost:2181 test
```
Author: Davies Liu <davies@databricks.com>
Author: Tathagata Das <tdas@databricks.com>
Closes #3715 from davies/kafka and squashes the following commits:
d93bfe0 [Davies Liu] Update make-distribution.sh
4280d04 [Davies Liu] address comments
e6d0427 [Davies Liu] Merge branch 'master' of github.com:apache/spark into kafka
f257071 [Davies Liu] add tests for null in RDD
23b039a [Davies Liu] address comments
9af51c4 [Davies Liu] Merge branch 'kafka' of github.com:davies/spark into kafka
a74da87 [Davies Liu] address comments
dc1eed0 [Davies Liu] Update kafka_wordcount.py
31e2317 [Davies Liu] Update kafka_wordcount.py
370ba61 [Davies Liu] Update kafka.py
97386b3 [Davies Liu] address comment
2c567a5 [Davies Liu] update logging and comment
33730d1 [Davies Liu] Merge branch 'master' of github.com:apache/spark into kafka
adeeb38 [Davies Liu] Merge pull request #3 from tdas/kafka-python-api
aea8953 [Tathagata Das] Kafka-assembly for Python API
eea16a7 [Davies Liu] refactor
f6ce899 [Davies Liu] add example and fix bugs
98c8d17 [Davies Liu] fix python style
5697a01 [Davies Liu] bypass decoder in scala
048dbe6 [Davies Liu] fix python style
75d485e [Davies Liu] add mqtt
07923c4 [Davies Liu] support kafka in Python
Diffstat (limited to 'python/pyspark')
-rw-r--r-- | python/pyspark/serializers.py | 9 | ||||
-rw-r--r-- | python/pyspark/streaming/kafka.py | 83 | ||||
-rw-r--r-- | python/pyspark/tests.py | 10 |
3 files changed, 100 insertions, 2 deletions
diff --git a/python/pyspark/serializers.py b/python/pyspark/serializers.py index b8bda83517..0ffb41d02f 100644 --- a/python/pyspark/serializers.py +++ b/python/pyspark/serializers.py @@ -70,6 +70,7 @@ class SpecialLengths(object): PYTHON_EXCEPTION_THROWN = -2 TIMING_DATA = -3 END_OF_STREAM = -4 + NULL = -5 class Serializer(object): @@ -133,6 +134,8 @@ class FramedSerializer(Serializer): def _write_with_length(self, obj, stream): serialized = self.dumps(obj) + if serialized is None: + raise ValueError("serialized value should not be None") if len(serialized) > (1 << 31): raise ValueError("can not serialize object larger than 2G") write_int(len(serialized), stream) @@ -145,8 +148,10 @@ class FramedSerializer(Serializer): length = read_int(stream) if length == SpecialLengths.END_OF_DATA_SECTION: raise EOFError + elif length == SpecialLengths.NULL: + return None obj = stream.read(length) - if obj == "": + if len(obj) < length: raise EOFError return self.loads(obj) @@ -484,6 +489,8 @@ class UTF8Deserializer(Serializer): length = read_int(stream) if length == SpecialLengths.END_OF_DATA_SECTION: raise EOFError + elif length == SpecialLengths.NULL: + return None s = stream.read(length) return s.decode("utf-8") if self.use_unicode else s diff --git a/python/pyspark/streaming/kafka.py b/python/pyspark/streaming/kafka.py new file mode 100644 index 0000000000..19ad71f99d --- /dev/null +++ b/python/pyspark/streaming/kafka.py @@ -0,0 +1,83 @@ +# +# 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. +# + +from py4j.java_collections import MapConverter +from py4j.java_gateway import java_import, Py4JError + +from pyspark.storagelevel import StorageLevel +from pyspark.serializers import PairDeserializer, NoOpSerializer +from pyspark.streaming import DStream + +__all__ = ['KafkaUtils', 'utf8_decoder'] + + +def utf8_decoder(s): + """ Decode the unicode as UTF-8 """ + return s and s.decode('utf-8') + + +class KafkaUtils(object): + + @staticmethod + def createStream(ssc, zkQuorum, groupId, topics, kafkaParams={}, + storageLevel=StorageLevel.MEMORY_AND_DISK_SER_2, + keyDecoder=utf8_decoder, valueDecoder=utf8_decoder): + """ + Create an input stream that pulls messages from a Kafka Broker. + + :param ssc: StreamingContext object + :param zkQuorum: Zookeeper quorum (hostname:port,hostname:port,..). + :param groupId: The group id for this consumer. + :param topics: Dict of (topic_name -> numPartitions) to consume. + Each partition is consumed in its own thread. + :param kafkaParams: Additional params for Kafka + :param storageLevel: RDD storage level. + :param keyDecoder: A function used to decode key (default is utf8_decoder) + :param valueDecoder: A function used to decode value (default is utf8_decoder) + :return: A DStream object + """ + java_import(ssc._jvm, "org.apache.spark.streaming.kafka.KafkaUtils") + + kafkaParams.update({ + "zookeeper.connect": zkQuorum, + "group.id": groupId, + "zookeeper.connection.timeout.ms": "10000", + }) + if not isinstance(topics, dict): + raise TypeError("topics should be dict") + jtopics = MapConverter().convert(topics, ssc.sparkContext._gateway._gateway_client) + jparam = MapConverter().convert(kafkaParams, ssc.sparkContext._gateway._gateway_client) + jlevel = ssc._sc._getJavaStorageLevel(storageLevel) + + def getClassByName(name): + return ssc._jvm.org.apache.spark.util.Utils.classForName(name) + + try: + array = getClassByName("[B") + decoder = getClassByName("kafka.serializer.DefaultDecoder") + jstream = ssc._jvm.KafkaUtils.createStream(ssc._jssc, array, array, decoder, decoder, + jparam, jtopics, jlevel) + except Py4JError, e: + # TODO: use --jar once it also work on driver + if not e.message or 'call a package' in e.message: + print "No kafka package, please put the assembly jar into classpath:" + print " $ bin/spark-submit --driver-class-path external/kafka-assembly/target/" + \ + "scala-*/spark-streaming-kafka-assembly-*.jar" + raise e + ser = PairDeserializer(NoOpSerializer(), NoOpSerializer()) + stream = DStream(jstream, ssc, ser) + return stream.map(lambda (k, v): (keyDecoder(k), valueDecoder(v))) diff --git a/python/pyspark/tests.py b/python/pyspark/tests.py index fef6c92875..c7d0622d65 100644 --- a/python/pyspark/tests.py +++ b/python/pyspark/tests.py @@ -47,9 +47,10 @@ else: from pyspark.conf import SparkConf from pyspark.context import SparkContext +from pyspark.rdd import RDD from pyspark.files import SparkFiles from pyspark.serializers import read_int, BatchedSerializer, MarshalSerializer, PickleSerializer, \ - CloudPickleSerializer, CompressedSerializer + CloudPickleSerializer, CompressedSerializer, UTF8Deserializer, NoOpSerializer from pyspark.shuffle import Aggregator, InMemoryMerger, ExternalMerger, ExternalSorter from pyspark.sql import SQLContext, IntegerType, Row, ArrayType, StructType, StructField, \ UserDefinedType, DoubleType @@ -716,6 +717,13 @@ class RDDTests(ReusedPySparkTestCase): wr_s21 = rdd.sample(True, 0.4, 21).collect() self.assertNotEqual(set(wr_s11), set(wr_s21)) + def test_null_in_rdd(self): + jrdd = self.sc._jvm.PythonUtils.generateRDDWithNull(self.sc._jsc) + rdd = RDD(jrdd, self.sc, UTF8Deserializer()) + self.assertEqual([u"a", None, u"b"], rdd.collect()) + rdd = RDD(jrdd, self.sc, NoOpSerializer()) + self.assertEqual(["a", None, "b"], rdd.collect()) + def test_multiple_python_java_RDD_conversions(self): # Regression test for SPARK-5361 data = [ |