pyspark NameError：未定义全局名称“累加器”

Question

I followed the quick start tutorial.

My script is

from pyspark import SparkContext

logFile = 'README.md'
sc = SparkContext('local', 'Simple App')
logData = sc.textFile(logFile).cache()

numAs = logData.filter(lambda s: 'a' in s).count()
numBs = logData.filter(lambda s: 'b' in s).count()

print 'Lines with a: %i, lines with b: %i' % (numAs, numBs)

I ran the script on the command line

$SPARK_HOME/bin/spark-submit --master local[2]  SimpleApp.py

Traceback (most recent call last):
File "/home/huayu/Programs/Machine_learning/spark_exe/quick_start/SimpleApp.py", line 4, in sc = SparkContext('local', 'Simple App')
File "/home/huayu/Downloads/Software/spark/python/pyspark/context.py", line 115, in init conf, jsc, profiler_cls)
File "/home/huayu/Downloads/Software/spark/python/pyspark/context.py", line 174, in _do_init self._accumulatorServer = accumulators._start_update_server()
NameError: global name 'accumulators' is not defined

When I ran python SimpleApp.py , it worked fine.

I got Spark from https://github.com/GUG11/spark (version 2.1.0) and I uses python 2.7.12.

There is another problem pertaining to Spark accumulator but the error information in my problem is different. pyspark ImportError: cannot import name accumulators

Answer 1

You did miss to add getOrCreate() which actually creates the Spark Context/Session In 2021 you would rather use the Spark session then the Spark Context as it can be now found on the same link http://spark.apache.org/docs/latest/quick-start.html#self-contained-applications

"""SimpleApp.py"""
from pyspark.sql import SparkSession

logFile = "YOUR_SPARK_HOME/README.md"  # Should be some file on your system
spark = SparkSession.builder.appName("SimpleApp").getOrCreate()
logData = spark.read.text(logFile).cache()

numAs = logData.filter(logData.value.contains('a')).count()
numBs = logData.filter(logData.value.contains('b')).count()

print("Lines with a: %i, lines with b: %i" % (numAs, numBs))

spark.stop()