[SPARK-8378] [STREAMING] Add the Python API for Flume

Author: zsxwing <zsxwing@gmail.com>

Closes #6830 from zsxwing/flume-python and squashes the following commits:

78dfdac [zsxwing] Fix the compile error in the test code
f1bf3c0 [zsxwing] Address TD's comments
0449723 [zsxwing] Add sbt goal streaming-flume-assembly/assembly
e93736b [zsxwing] Fix the test case for determine_modules_to_test
9d5821e [zsxwing] Fix pyspark_core dependencies
f9ee681 [zsxwing] Merge branch 'master' into flume-python
7a55837 [zsxwing] Add streaming_flume_assembly to run-tests.py
b96b0de [zsxwing] Merge branch 'master' into flume-python
ce85e83 [zsxwing] Fix incompatible issues for Python 3
01cbb3d [zsxwing] Add import sys
152364c [zsxwing] Fix the issue that StringIO doesn't work in Python 3
14ba0ff [zsxwing] Add flume-assembly for sbt building
b8d5551 [zsxwing] Merge branch 'master' into flume-python
4762c34 [zsxwing] Fix the doc
0336579 [zsxwing] Refactor Flume unit tests and also add tests for Python API
9f33873 [zsxwing] Add the Python API for Flume

2 files changed, 19 insertions, 1 deletions

diff --git a/docs/streaming-flume-integration.md b/docs/streaming-flume-integration.md
index 8d6e743709..de0461010d 100644
--- a/docs/streaming-flume-integration.md
+++ b/docs/streaming-flume-integration.md
@@ -58,6 +58,15 @@ configuring Flume agents.
 	See the [API docs](api/java/index.html?org/apache/spark/streaming/flume/FlumeUtils.html)
 	and the [example]({{site.SPARK_GITHUB_URL}}/tree/master/examples/src/main/java/org/apache/spark/examples/streaming/JavaFlumeEventCount.java).
 	</div>
+	<div data-lang="python" markdown="1">
+		from pyspark.streaming.flume import FlumeUtils
+
+		flumeStream = FlumeUtils.createStream(streamingContext, [chosen machine's hostname], [chosen port])
+
+	By default, the Python API will decode Flume event body as UTF8 encoded strings. You can specify your custom decoding function to decode the body byte arrays in Flume events to any arbitrary data type. 
+	See the [API docs](api/python/pyspark.streaming.html#pyspark.streaming.flume.FlumeUtils)
+	and the [example]({{site.SPARK_GITHUB_URL}}/blob/master/examples/src/main/python/streaming/flume_wordcount.py).
+	</div>
 	</div>
 
 	Note that the hostname should be the same as the one used by the resource manager in the
@@ -135,6 +144,15 @@ configuring Flume agents.
 		JavaReceiverInputDStream<SparkFlumeEvent>flumeStream =
 			FlumeUtils.createPollingStream(streamingContext, [sink machine hostname], [sink port]);
 	</div>
+	<div data-lang="python" markdown="1">
+		from pyspark.streaming.flume import FlumeUtils
+
+		addresses = [([sink machine hostname 1], [sink port 1]), ([sink machine hostname 2], [sink port 2])]
+		flumeStream = FlumeUtils.createPollingStream(streamingContext, addresses)
+
+	By default, the Python API will decode Flume event body as UTF8 encoded strings. You can specify your custom decoding function to decode the body byte arrays in Flume events to any arbitrary data type.
+	See the [API docs](api/python/pyspark.streaming.html#pyspark.streaming.flume.FlumeUtils).
+	</div>
 	</div>
 
 	See the Scala example [FlumePollingEventCount]({{site.SPARK_GITHUB_URL}}/tree/master/examples/src/main/scala/org/apache/spark/examples/streaming/FlumePollingEventCount.scala).
diff --git a/docs/streaming-programming-guide.md b/docs/streaming-programming-guide.md
index b784d59666..e72d5580da 100644
--- a/docs/streaming-programming-guide.md
+++ b/docs/streaming-programming-guide.md
@@ -683,7 +683,7 @@ for Java, and [StreamingContext](api/python/pyspark.streaming.html#pyspark.strea
 {:.no_toc}
 
 <span class="badge" style="background-color: grey">Python API</span> As of Spark {{site.SPARK_VERSION_SHORT}},
-out of these sources, *only* Kafka is available in the Python API. We will add more advanced sources in the Python API in future.
+out of these sources, *only* Kafka and Flume are available in the Python API. We will add more advanced sources in the Python API in future.
 
 This category of sources require interfacing with external non-Spark libraries, some of them with
 complex dependencies (e.g., Kafka and Flume). Hence, to minimize issues related to version conflicts