Coverage for pyspark/streaming/kinesis.py : 35%

# 

# 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, 

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# See the License for the specific language governing permissions and 

# limitations under the License. 

# 

from pyspark.serializers import NoOpSerializer 

from pyspark.storagelevel import StorageLevel 

from pyspark.streaming import DStream 

from pyspark.util import _print_missing_jar 

__all__ = ['KinesisUtils', 'InitialPositionInStream', 'utf8_decoder'] 

def utf8_decoder(s): 

""" Decode the unicode as UTF-8 """ 

if s is None: 

return None 

return s.decode('utf-8') 

class KinesisUtils(object): 

@staticmethod 

def createStream(ssc, kinesisAppName, streamName, endpointUrl, regionName, 

initialPositionInStream, checkpointInterval, 

storageLevel=StorageLevel.MEMORY_AND_DISK_2, 

awsAccessKeyId=None, awsSecretKey=None, decoder=utf8_decoder, 

stsAssumeRoleArn=None, stsSessionName=None, stsExternalId=None): 

""" 

Create an input stream that pulls messages from a Kinesis stream. This uses the 

Kinesis Client Library (KCL) to pull messages from Kinesis. 

Parameters 

---------- 

ssc : :class:`StreamingContext` 

StreamingContext object 

kinesisAppName : str 

Kinesis application name used by the Kinesis Client Library (KCL) to 

update DynamoDB 

streamName : str 

Kinesis stream name 

endpointUrl : str 

Url of Kinesis service (e.g., https://kinesis.us-east-1.amazonaws.com) 

regionName : str 

Name of region used by the Kinesis Client Library (KCL) to update 

DynamoDB (lease coordination and checkpointing) and CloudWatch (metrics) 

initialPositionInStream : int 

In the absence of Kinesis checkpoint info, this is the 

worker's initial starting position in the stream. The 

values are either the beginning of the stream per Kinesis' 

limit of 24 hours (InitialPositionInStream.TRIM_HORIZON) or 

the tip of the stream (InitialPositionInStream.LATEST). 

checkpointInterval : int 

Checkpoint interval(in seconds) for Kinesis checkpointing. See the Kinesis 

Spark Streaming documentation for more details on the different 

types of checkpoints. 

storageLevel : :class:`pyspark.StorageLevel`, optional 

Storage level to use for storing the received objects (default is 

StorageLevel.MEMORY_AND_DISK_2) 

awsAccessKeyId : str, optional 

AWS AccessKeyId (default is None. If None, will use 

DefaultAWSCredentialsProviderChain) 

awsSecretKey : str, optional 

AWS SecretKey (default is None. If None, will use 

DefaultAWSCredentialsProviderChain) 

decoder : function, optional 

A function used to decode value (default is utf8_decoder) 

stsAssumeRoleArn : str, optional 

ARN of IAM role to assume when using STS sessions to read from 

the Kinesis stream (default is None). 

stsSessionName : str, optional 

Name to uniquely identify STS sessions used to read from Kinesis 

stream, if STS is being used (default is None). 

stsExternalId : str, optional 

External ID that can be used to validate against the assumed IAM 

role's trust policy, if STS is being used (default is None). 

Returns 

------- 

A DStream object 

Notes 

----- 

The given AWS credentials will get saved in DStream checkpoints if checkpointing 

is enabled. Make sure that your checkpoint directory is secure. 

""" 

jlevel = ssc._sc._getJavaStorageLevel(storageLevel) 

jduration = ssc._jduration(checkpointInterval) 

try: 

helper = ssc._jvm.org.apache.spark.streaming.kinesis.KinesisUtilsPythonHelper() 

except TypeError as e: 

if str(e) == "'JavaPackage' object is not callable": 

_print_missing_jar( 

"Streaming's Kinesis", 

"streaming-kinesis-asl", 

"streaming-kinesis-asl-assembly", 

ssc.sparkContext.version) 

raise 

jstream = helper.createStream(ssc._jssc, kinesisAppName, streamName, endpointUrl, 

regionName, initialPositionInStream, jduration, jlevel, 

awsAccessKeyId, awsSecretKey, stsAssumeRoleArn, 

stsSessionName, stsExternalId) 

stream = DStream(jstream, ssc, NoOpSerializer()) 

return stream.map(lambda v: decoder(v)) 

class InitialPositionInStream(object): 

LATEST, TRIM_HORIZON = (0, 1)