code

Use a dictionary to count the number of hits by hostname from a proxy log file, where the 7th tab delimited entry per line is the host. KeyError is the exception thrown if a dictionary doesn’t yet contain the key being referred to.

def parselog(infile):
  i = 0
  fbook = 0
  totals = {}

  for line in infile.xreadlines():
    desthost = line.split("\t")[6]
 
    try:
      totals[desthost] += 1
    except KeyError:
      totals[desthost] = 1

    if desthost.find("facebook") > 0:
      fbook +=1

    i += 1
 
    return i, fbook, totals