Spark cluster text processing vs. single node

gistfile1.txt

From this little example created by myself I learned, that it is always important to think in the distributed MapReduce paradigm when getting hands on spark.
Operations that are costly calculations in a centralized manner should be avoided on the cluster.

texprocessing.py

import json
import re

def matcher( str ):
   for match in re.finditer(r'(POST|HEAD|GET).*HTTP......[0-9]*.[0-9]*', str):
            if match:
                res = match.group().replace('"','')
                words = res.split()
                key = " ".join(words[0:len(words)-1])
                requests = int(words[len(words)-1])
                print key
                if key in api_requests:
                    api_requests[key][0] += requests
                    api_requests[key][1] += 1
                else:
                    api_requests[key] = [requests]
                    api_requests[key].append(1)
        
            else:
                print "Nothing found"
   return

with open("logfile.txt", "r") as file:
    # new dictionary
    api_requests = {}
    for line in file:
        data = json.loads(line)
        elm = data["body"]
        matcher(elm)

textprocessingCluster.py

from pyspark import SparkContext, SparkConf
import json 
import re

api_pattern = re.compile(r'(POST|HEAD|GET).*HTTP......[0-9]*.[0-9]*')

def matcher( str ):
    match = api_pattern.search(str)
    if match:
        res = match.group().replace('"','')
        words = res.split()
        key = " ".join(words[0:len(words)-1])
        return key

    else:
        return

conf = SparkConf().setAppName("test").setMaster("local")
sc = SparkContext(conf=conf)

distFile = sc.textFile("logfile.txt")

api_requests = distFile.map(lambda line: (matcher(json.loads(line)["body"]),1)).filter(lambda (x, y): x is not None).reduceByKey(lambda a, b: a + b)

list_test = api_requests.map(lambda (x, y): list((x,y)) )

for name in list_test.collect():
  print(name[1])

api_requests.saveAsTextFile("api_requests")

# spark-submit C:\Users\koljacorneliusmaier\Documents\textprocessingCluster.py