The Tor Browser / file revision

 #!/usr/bin/env python

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 # Write out detailed histogram information, including the ranges of the

 # buckets specified by each histogram.

 import sys

 import re

 import histogram_tools

 import json

 from collections import OrderedDict

 # Keep this in sync with TelemetryPing.

 startup_histogram_re = re.compile("SQLITE|HTTP|SPDY|CACHE|DNS")

 def main(argv):

     filename = argv[0]

     all_histograms = OrderedDict()

     for histogram in histogram_tools.from_file(filename):

         name = histogram.name()

         parameters = OrderedDict()

         table = {

             'boolean': '2',

             'flag': '3',

             'enumerated': '1',

             'linear': '1',

             'exponential': '0'

             }

         # Use __setitem__ because Python lambdas are so limited.

         histogram_tools.table_dispatch(histogram.kind(), table,

                                        lambda k: parameters.__setitem__('kind', k))

         if histogram.low() == 0:

             parameters['min'] = 1

         else:

             parameters['min'] = histogram.low()

         try:

             buckets = histogram.ranges()

             parameters['buckets'] = buckets

             parameters['max'] = buckets[-1]

             parameters['bucket_count'] = len(buckets)

         except histogram_tools.DefinitionException:

             continue

         all_histograms.update({ name: parameters });

         if startup_histogram_re.search(name) is not None:

             all_histograms.update({ "STARTUP_" + name: parameters })

     print json.dumps({ 'histograms': all_histograms})

 main(sys.argv[1:])