spark-instrumented-optimizer/python/pyspark/streaming/mqtt.py
Prabeesh K 853809e948 [SPARK-5155] [PYSPARK] [STREAMING] Mqtt streaming support in Python
This PR is based on #4229, thanks prabeesh.

Closes #4229

Author: Prabeesh K <prabsmails@gmail.com>
Author: zsxwing <zsxwing@gmail.com>
Author: prabs <prabsmails@gmail.com>
Author: Prabeesh K <prabeesh.k@namshi.com>

Closes #7833 from zsxwing/pr4229 and squashes the following commits:

9570bec [zsxwing] Fix the variable name and check null in finally
4a9c79e [zsxwing] Fix pom.xml indentation
abf5f18 [zsxwing] Merge branch 'master' into pr4229
935615c [zsxwing] Fix the flaky MQTT tests
47278c5 [zsxwing] Include the project class files
478f844 [zsxwing] Add unpack
5f8a1d4 [zsxwing] Make the maven build generate the test jar for Python MQTT tests
734db99 [zsxwing] Merge branch 'master' into pr4229
126608a [Prabeesh K] address the comments
b90b709 [Prabeesh K] Merge pull request #1 from zsxwing/pr4229
d07f454 [zsxwing] Register StreamingListerner before starting StreamingContext; Revert unncessary changes; fix the python unit test
a6747cb [Prabeesh K] wait for starting the receiver before publishing data
87fc677 [Prabeesh K] address the comments:
97244ec [zsxwing] Make sbt build the assembly test jar for streaming mqtt
80474d1 [Prabeesh K] fix
1f0cfe9 [Prabeesh K] python style fix
e1ee016 [Prabeesh K] scala style fix
a5a8f9f [Prabeesh K] added Python test
9767d82 [Prabeesh K] implemented Python-friendly class
a11968b [Prabeesh K] fixed python style
795ec27 [Prabeesh K] address comments
ee387ae [Prabeesh K] Fix assembly jar location of mqtt-assembly
3f4df12 [Prabeesh K] updated version
b34c3c1 [prabs] adress comments
3aa7fff [prabs] Added Python streaming mqtt word count example
b7d42ff [prabs] Mqtt streaming support in Python
2015-08-10 16:33:23 -07:00

73 lines
2.9 KiB
Python

#
# 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_gateway import Py4JJavaError
from pyspark.storagelevel import StorageLevel
from pyspark.serializers import UTF8Deserializer
from pyspark.streaming import DStream
__all__ = ['MQTTUtils']
class MQTTUtils(object):
@staticmethod
def createStream(ssc, brokerUrl, topic,
storageLevel=StorageLevel.MEMORY_AND_DISK_SER_2):
"""
Create an input stream that pulls messages from a Mqtt Broker.
:param ssc: StreamingContext object
:param brokerUrl: Url of remote mqtt publisher
:param topic: topic name to subscribe to
:param storageLevel: RDD storage level.
:return: A DStream object
"""
jlevel = ssc._sc._getJavaStorageLevel(storageLevel)
try:
helperClass = ssc._jvm.java.lang.Thread.currentThread().getContextClassLoader() \
.loadClass("org.apache.spark.streaming.mqtt.MQTTUtilsPythonHelper")
helper = helperClass.newInstance()
jstream = helper.createStream(ssc._jssc, brokerUrl, topic, jlevel)
except Py4JJavaError as e:
if 'ClassNotFoundException' in str(e.java_exception):
MQTTUtils._printErrorMsg(ssc.sparkContext)
raise e
return DStream(jstream, ssc, UTF8Deserializer())
@staticmethod
def _printErrorMsg(sc):
print("""
________________________________________________________________________________________________
Spark Streaming's MQTT libraries not found in class path. Try one of the following.
1. Include the MQTT library and its dependencies with in the
spark-submit command as
$ bin/spark-submit --packages org.apache.spark:spark-streaming-mqtt:%s ...
2. Download the JAR of the artifact from Maven Central http://search.maven.org/,
Group Id = org.apache.spark, Artifact Id = spark-streaming-mqtt-assembly, Version = %s.
Then, include the jar in the spark-submit command as
$ bin/spark-submit --jars <spark-streaming-mqtt-assembly.jar> ...
________________________________________________________________________________________________
""" % (sc.version, sc.version))