| # |
| # 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 |
| if sys.version >= "3": |
| from io import BytesIO |
| else: |
| from StringIO import StringIO |
| import warnings |
| |
| from py4j.protocol import Py4JJavaError |
| |
| from pyspark.storagelevel import StorageLevel |
| from pyspark.serializers import PairDeserializer, NoOpSerializer, UTF8Deserializer, read_int |
| from pyspark.streaming import DStream |
| |
| __all__ = ['FlumeUtils', 'utf8_decoder'] |
| |
| |
| def utf8_decoder(s): |
| """ Decode the unicode as UTF-8 """ |
| if s is None: |
| return None |
| return s.decode('utf-8') |
| |
| |
| class FlumeUtils(object): |
| |
| @staticmethod |
| def createStream(ssc, hostname, port, |
| storageLevel=StorageLevel.MEMORY_AND_DISK_2, |
| enableDecompression=False, |
| bodyDecoder=utf8_decoder): |
| """ |
| Create an input stream that pulls events from Flume. |
| |
| :param ssc: StreamingContext object |
| :param hostname: Hostname of the slave machine to which the flume data will be sent |
| :param port: Port of the slave machine to which the flume data will be sent |
| :param storageLevel: Storage level to use for storing the received objects |
| :param enableDecompression: Should netty server decompress input stream |
| :param bodyDecoder: A function used to decode body (default is utf8_decoder) |
| :return: A DStream object |
| |
| .. note:: Deprecated in 2.3.0. Flume support is deprecated as of Spark 2.3.0. |
| See SPARK-22142. |
| """ |
| warnings.warn( |
| "Deprecated in 2.3.0. Flume support is deprecated as of Spark 2.3.0. " |
| "See SPARK-22142.", |
| DeprecationWarning) |
| jlevel = ssc._sc._getJavaStorageLevel(storageLevel) |
| helper = FlumeUtils._get_helper(ssc._sc) |
| jstream = helper.createStream(ssc._jssc, hostname, port, jlevel, enableDecompression) |
| return FlumeUtils._toPythonDStream(ssc, jstream, bodyDecoder) |
| |
| @staticmethod |
| def createPollingStream(ssc, addresses, |
| storageLevel=StorageLevel.MEMORY_AND_DISK_2, |
| maxBatchSize=1000, |
| parallelism=5, |
| bodyDecoder=utf8_decoder): |
| """ |
| Creates an input stream that is to be used with the Spark Sink deployed on a Flume agent. |
| This stream will poll the sink for data and will pull events as they are available. |
| |
| :param ssc: StreamingContext object |
| :param addresses: List of (host, port)s on which the Spark Sink is running. |
| :param storageLevel: Storage level to use for storing the received objects |
| :param maxBatchSize: The maximum number of events to be pulled from the Spark sink |
| in a single RPC call |
| :param parallelism: Number of concurrent requests this stream should send to the sink. |
| Note that having a higher number of requests concurrently being pulled |
| will result in this stream using more threads |
| :param bodyDecoder: A function used to decode body (default is utf8_decoder) |
| :return: A DStream object |
| |
| .. note:: Deprecated in 2.3.0. Flume support is deprecated as of Spark 2.3.0. |
| See SPARK-22142. |
| """ |
| warnings.warn( |
| "Deprecated in 2.3.0. Flume support is deprecated as of Spark 2.3.0. " |
| "See SPARK-22142.", |
| DeprecationWarning) |
| jlevel = ssc._sc._getJavaStorageLevel(storageLevel) |
| hosts = [] |
| ports = [] |
| for (host, port) in addresses: |
| hosts.append(host) |
| ports.append(port) |
| helper = FlumeUtils._get_helper(ssc._sc) |
| jstream = helper.createPollingStream( |
| ssc._jssc, hosts, ports, jlevel, maxBatchSize, parallelism) |
| return FlumeUtils._toPythonDStream(ssc, jstream, bodyDecoder) |
| |
| @staticmethod |
| def _toPythonDStream(ssc, jstream, bodyDecoder): |
| ser = PairDeserializer(NoOpSerializer(), NoOpSerializer()) |
| stream = DStream(jstream, ssc, ser) |
| |
| def func(event): |
| headersBytes = BytesIO(event[0]) if sys.version >= "3" else StringIO(event[0]) |
| headers = {} |
| strSer = UTF8Deserializer() |
| for i in range(0, read_int(headersBytes)): |
| key = strSer.loads(headersBytes) |
| value = strSer.loads(headersBytes) |
| headers[key] = value |
| body = bodyDecoder(event[1]) |
| return (headers, body) |
| return stream.map(func) |
| |
| @staticmethod |
| def _get_helper(sc): |
| try: |
| return sc._jvm.org.apache.spark.streaming.flume.FlumeUtilsPythonHelper() |
| except TypeError as e: |
| if str(e) == "'JavaPackage' object is not callable": |
| FlumeUtils._printErrorMsg(sc) |
| raise |
| |
| @staticmethod |
| def _printErrorMsg(sc): |
| print(""" |
| ________________________________________________________________________________________________ |
| |
| Spark Streaming's Flume libraries not found in class path. Try one of the following. |
| |
| 1. Include the Flume library and its dependencies with in the |
| spark-submit command as |
| |
| $ bin/spark-submit --packages org.apache.spark:spark-streaming-flume:%s ... |
| |
| 2. Download the JAR of the artifact from Maven Central http://search.maven.org/, |
| Group Id = org.apache.spark, Artifact Id = spark-streaming-flume-assembly, Version = %s. |
| Then, include the jar in the spark-submit command as |
| |
| $ bin/spark-submit --jars <spark-streaming-flume-assembly.jar> ... |
| |
| ________________________________________________________________________________________________ |
| |
| """ % (sc.version, sc.version)) |