Check in cq_stats.py

infra/tools/cq_stats/cq_stats.py

Index: infra/tools/cq_stats/cq_stats.py
diff --git a/infra/tools/cq_stats/cq_stats.py b/infra/tools/cq_stats/cq_stats.py
new file mode 100755
index 0000000000000000000000000000000000000000..c5f81b515855b30e6e4faf8c6e34a3093bef8c5c
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+++ b/infra/tools/cq_stats/cq_stats.py
@@ -0,0 +1,1206 @@
+#!/usr/bin/python
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+'''Generate stats of CQ usage.'''
+
+import argparse
+import calendar
+import collections
+import datetime
+import dateutil.parser
+import dateutil.tz
+from xml.etree import ElementTree
+import infra.libs.logs
+import json
+import logging
+from multiprocessing.pool import ThreadPool
+import numbers
+import numpy
+import re
+import subprocess
+import sys
+import time
+import urllib
+import urllib2
+import urlparse
+
+
+STATS_URL = 'http://chromium-cq-status.appspot.com'
+# Expects % project.
+TREE_STATUS_URL = 'http://%s-status.appspot.com'
+PROJECTS = {
+    'chromium': {
+        'tree-status': TREE_STATUS_URL % 'chromium',
+        'type': 'git',
+        'repo': 'https://chromium.googlesource.com/chromium/src',
+    },
+    'blink': {
+        'tree-status': TREE_STATUS_URL % 'blink',
+        'type': 'svn',
+        'repo': 'svn://svn.chromium.org/blink/trunk/',
+    },
+}
+# Map of intervals to minutes.
+INTERVALS = {
+    'week': 60 * 24 * 7,
+    'day': 60 * 24,
+    'hour': 60,
+    '15min': 15,
+}
+VALID_REASONS = collections.OrderedDict([
+    ('manual-cancel', {
+        'item': 'stopped manually',
+        'message': 'stopped manually (CQ box was unchecked)',
+    }),
+    ('missing-lgtm',  {
+        'item': 'missed LGTM',
+        'message': 'are missing LGTM',
+    }),
+    ('not-lgtm',  {
+        'item': 'NOT LGTMs',
+        'message': 'have been disapproved (NOT LGTM)',
+    }),
+    ('failed-patch', {
+        'item': 'failures',
+        'message': 'failed to apply patch',
+    }),
+    ('invalid-delimiter', {
+        'item': 'errors',
+        'message': 'have incorrect CQ_EXTRA_TRYBOTS flag',
+    }),
+    ('failed-presubmit-bot', {
+        'item': 'failures',
+        'message': 'failed presubmit bot (often due to missing OWNERS LGTM)',
+    }),
+])
+FLAKY_REASONS = collections.OrderedDict([
+    ('failed-commit', {
+        'item': 'failures',
+        'message': 'failed to commit',
+    }),
+    ('failed-jobs', {
+        'item': 'failures',
+        'message': 'failed jobs (excluding presubmit)',
+    }),
+    ('failed-to-trigger', {
+        'item': 'failures',
+        'message': 'failed to trigger jobs',
+    }),
+    ('failed-presubmit-check', {
+        'item': 'failures',
+        'message': 'failed presubmit check',
+    }),
+])
+KNOWN_REASONS = collections.OrderedDict()
+KNOWN_REASONS.update(VALID_REASONS)
+KNOWN_REASONS.update(FLAKY_REASONS)
+
+REASONS = collections.OrderedDict()
+REASONS.update(KNOWN_REASONS)
+REASONS['failed-unknown'] = {
+    'item': 'failures',
+    'message': 'failed for any other reason',
+}
+
+
+def parse_args():
+  parser = argparse.ArgumentParser(description=sys.modules['__main__'].__doc__)
+  parser.add_argument(
+      '--project',
+      required=True,
+      choices=PROJECTS.keys(),
+      help='Collect stats about this project.')
+  parser.add_argument(
+      '--bot', type=str, dest='bots',
+      action='append',
+      default=['blink-deps-roller@chromium.org',
+               'chrome-admin@google.com',
+               'chrome-release@google.com',
+               'chromeos-commit-bot@chromium.org',
+               'skia-deps-roller@chromium.org',
+              ],
+      help=('Add an author to be treated as a bot. '
+            'Repeat to add several bots. Default: %(default)s.'))
+  parser.add_argument(
+      '--seq', action='store_true',
+      help='Run everything sequentially for debugging.')
+  parser.add_argument(
+      '--thread-pool', type=int, default=200,
+      help='Fetch data using this many parallel threads. Default=%(default)s.')
+  parser.add_argument(
+      '--list-rejections', action='store_true',
+      help='List rejected CLs and reasons for rejection.')
+  parser.add_argument(
+      '--list-false-rejections', action='store_true',
+      help='List CLs that were committed in more than one attempt.')
+  parser.add_argument(
+      '--use-logs', action='store_true',
+      default=True,
+      help=('On by default. '
+            'Fetch the detailed logs and recompute the stats in this script, '
+            'instead of fetching precomputed stats. '
+            'Slower, but more accurate, and helps validate the cached stats.'))
+  parser.add_argument(
+      '--use-cache',
+      dest='use_logs',
+      action='store_false',
+      help=('Fetch the cached stats from the app. Opposite to --use-logs.'))
+  parser.add_argument(
+      '--date',
+      help='Start date of stats YYYY-MM-DD[ HH[:MM]]. Default: --range ago.')
+  parser.add_argument('--range',
+                      choices=INTERVALS.keys(),
+                      default='week',
+                      help='Time range to print stats for.')
+  infra.libs.logs.add_argparse_options(parser, default_level=logging.ERROR)
+
+  args = parser.parse_args()
+
+  if args.date:
+    args.date = date_from_string(args.date)
+  else:
+    args.date = (datetime.datetime.now() -
+                 datetime.timedelta(minutes=INTERVALS[args.range]))
+
+  return args
+
+
+def date_from_string(iso_str):
+  try:
+    return dateutil.parser.parse(iso_str)
+  except ValueError:
+    pass
+  raise ValueError('Unrecognized date/time format: %s' % iso_str)
+
+
+def date_from_timestamp(timestamp):
+  return datetime.datetime.fromtimestamp(float(timestamp))
+
+
+def date_from_git(date_str):
+  """If date_str is not valid or None, return None."""
+  if not date_str:
+    return None
+  date = None
+  try:
+    date = datetime.datetime.strptime(
+        date_str, '%a %b %d %H:%M:%S %Y')
+  except ValueError:
+    pass
+  return date
+
+
+def local_date_to_timestamp(date):
+  return time.mktime(date.timetuple())
+
+
+def local_to_utc(local_time):
+  timestamp = local_date_to_timestamp(local_time)
+  utcTime = datetime.datetime.utcfromtimestamp(timestamp)
+  return utcTime
+
+
+def fetch_json(url):
+  result = {'error': '404'}
+  delays = [0.0, 0.5, 1.0, 2.0]
+  for retry in range(len(delays)):
+    if retry:
+      time.sleep(delays[retry])
+    try:
+      result = json.loads(urllib2.urlopen(url).read())
+      return result
+    except (IOError, ValueError) as e:
+      logging.warning('Failed to fetch (attempt %d) %s: %s', retry + 1, url, e)
+  logging.error('Permanently failed to fetch %s: %s', url, e)
+  return result
+
+
+def fetch_tree_status(project, end_date, start_date=None, limit=1000):
+  """Fetch all tree events in the given interval.
+
+  Args:
+    project (str): e.g. 'chromium' or 'blink'.
+    end_date (datetime):
+    start_date (datetime): define the time interval in local timezone.
+    limit (int): max. number of events.
+
+  Returns:
+    List of events {'open': bool, 'date': datetime} sorted by date.
+  """
+  end_timestamp = int(time.mktime(end_date.timetuple()))
+  params = {
+      'format': 'json',
+      'limit': limit,
+      # Confusingly, chromium-status app defines the range as
+      # endTime <= t < startTime.
+      'startTime': end_timestamp,
+  }
+  if start_date:
+    params['endTime'] = int(time.mktime(start_date.timetuple()))
+  query = 'allstatus?' + urllib.urlencode(params)
+  url = urlparse.urljoin(PROJECTS[project]['tree-status'], query)
+  logging.debug('Fetching %s', url)
+  status = fetch_json(url)
+  # Bug in AE app: it may return events outside of time range.
+  def entry(event):
+    date_utc = date_from_string(event['date'])
+    date_local = date_from_timestamp(calendar.timegm(date_utc.utctimetuple()))
+    return {'date': date_local,
+            'open': event['general_state'] == 'open'}
+  def in_range(entry):
+    logging.debug('in_range(%r)', entry)
+    if entry['date'] >= end_date:
+      return False
+    if not start_date:
+      return True
+    return start_date <= entry['date']
+
+  if not status or type(status) is not list:
+    status = []
+  status = [entry(event) for event in status]
+  status = sorted([e for e in status if in_range(e)], key=lambda e: e['date'])
+  return status
+
+
+def fetch_git_page(repo_url, cursor=None, page_size=2000):
+  """Fetch one page worth of logs from gitiles."""
+  params = {
+      'pretty': 'full',
+      'format': 'JSON',
+      'n': page_size,
+  }
+  if cursor:
+    params.update({'s': cursor})
+  url = '%s/%s?%s' % (repo_url, '/+log/master', urllib.urlencode(params))
+  logging.debug('fetch_git_page: url = %s', url)
+  try:
+    # Strip off the anti-XSS string from the response.
+    response = urllib2.urlopen(url)
+    lines = [l.rstrip() for l in response if l.rstrip() != ")]}'"]
+    raw_data = ''.join(lines)
+    page = json.loads(raw_data)
+  except (IOError, ValueError) as e:
+    page = {}
+    logging.error('Failed to fetch a page: %s', e)
+  return page
+
+
+def fetch_git_logs(repo, from_date, to_date):
+  """Fetch all logs from Gitiles for the given date range.
+
+  Gitiles does not natively support time ranges, so we just fetch
+  everything until the range is covered. Assume that logs are ordered
+  in reverse chronological order.
+  """
+  cursor = ''
+  commit_date = to_date
+  data = []
+  while cursor is not None:
+    page = fetch_git_page(repo, cursor)
+    logs = page.get('log', [])
+    cursor = page.get('next')
+    for log in logs:
+      committer = log.get('committer', {})
+      commit_date = date_from_git(committer.get('time'))
+      if not commit_date:
+        continue
+      if commit_date > to_date:
+        continue
+      if commit_date < from_date:
+        break
+      data.append({
+          'author': log.get('author', {}).get('email'),
+          'date': commit_date,
+          'commit-bot': bool('commit-bot' in committer.get('email', '')),
+          'revision': log.get('commit'),
+      })
+
+    if commit_date < from_date:
+      break
+  return data
+
+
+def fetch_svn_logs(repo, from_date, to_date):
+  from_date = local_to_utc(from_date)
+  to_date = local_to_utc(to_date)
+  range_str = (
+      '{%s +0000}:{%s +0000}' % (from_date, to_date))
+  out = subprocess.check_output(
+      ['svn', 'log', '--with-all-revprops', '--xml', repo, '-r', range_str])
+  data = []
+  for logentry in ElementTree.XML(out).findall('logentry'):
+    date_str = logentry.find('date').text
+    date = date_from_string(date_str)
+    entry = {
+        'author': logentry.find('author').text,
+        'date': date,
+        'revprops': {},
+        'commit-bot': False,
+    }
+    revprops = logentry.find('revprops')
+    if revprops is not None:
+      for revprop in revprops.findall('property'):
+        entry['revprops'][revprop.attrib['name']] = revprop.text
+        if revprop.attrib['name'] == 'commit-bot':
+          entry['commit-bot'] = True
+    data.append(entry)
+  return data
+
+
+def fetch_stats(args, begin_date=None, stats_range=None):
+  if not begin_date:
+    begin_date = args.date
+  if not stats_range:
+    stats_range = args.range
+  if begin_date:
+    timestamp = (int(local_date_to_timestamp(begin_date)) +
+                 INTERVALS[stats_range] * 60)
+  else:
+    timestamp = int(time.time())
+
+  params = {
+      'project': args.project,
+      'interval_minutes': INTERVALS[stats_range],
+      'end': timestamp,
+      'count': 2, # Fetch requested and previous set, for comparison.
+  }
+
+  query = 'stats/query?' + urllib.urlencode(params)
+  url = urlparse.urljoin(STATS_URL, query)
+  logging.debug('Fetching %s', url)
+  return fetch_json(url)
+
+
+# "Dangerous default value []": pylint: disable=W0102
+def fetch_cq_logs(start_date=None, end_date=None, filters=[]):
+  begin_time = None
+  end_time = None
+  if start_date:
+    begin_time = int(time.mktime(start_date.timetuple()))
+  if end_date:
+    end_time = int(time.mktime(end_date.timetuple()))
+  results = []
+  cursor = None
+  while True:
+    params = {}
+    if begin_time:
+      params['begin'] = begin_time
+    if end_time:
+      params['end'] = end_time
+    if cursor:
+      params['cursor'] = cursor
+    query = 'query/%s?%s' % ('/'.join(filters), urllib.urlencode(params))
+    url = urlparse.urljoin(STATS_URL, query)
+    logging.debug('Fetching %s', url)
+    data = fetch_json(url)
+    results.extend(data.get('results', []))
+    logging.info('fetch_cq_logs: Got %d results', len(results))
+    logging.debug('  %s', '\n  '.join(['%s %s' % (
+        patch_url((r.get('fields', {}).get('issue', 0),
+                   r.get('fields', {}).get('patchset', 0))),
+        r.get('fields', {}).get('action', '')) for r in results]))
+    cursor = data.get('cursor', None)
+    if not data.get('more', False) or not cursor:
+      break
+
+  return results
+
+
+def default_stats():
+  """Generate all the required stats fields with default values."""
+  stats = {
+      'begin': datetime.datetime.now(),
+      'end': datetime.datetime(1, 1, 1),
+      'issue-count': 0,
+      'patchset-count': 0,
+      'attempt-count': 0,
+      'patch_stats': {},
+      'patchset-false-reject-count': 0,  # Deprecated stats?
+      'attempt-reject-count': 0,  # Num. of rejected attempts
+      'attempt-false-reject-count': 0,  # Num. of falsely rejected attempts
+      'false-rejections': [],  # patches with falsely rejected attempts
+      'rejections': [],        # patches with rejected attempts
+      'rejected-patches': set(),  # Patches that never committed
+      'patchset-commit-count': 0,
+      'patchset-total-commit-queue-durations': derive_list_stats([0]),
+      'patchset-durations': derive_list_stats([0]),
+      'patchset-committed-durations': derive_list_stats([0]),
+      'patchset-attempts': derive_list_stats([0]),
+      'patchset-committed-attempts': derive_list_stats([0]),
+      'jobs': {},
+      'tree': {'open': 0.0, 'total': 0.0},
+      'usage': {},
+  }
+  for reason in REASONS:
+    stats[reason] = []
+  return stats
+
+
+def organize_stats(stats, latest_init=None, previous_init=None):
+  """Changes cached lists of stats into dictionaries.
+
+  Args:
+    stats (dict): set of stats as returned by chromium-cq-status.
+
+  Returns:
+    result (dict): mapping ('latest' | 'previous') -> stat.name
+    -> <stats json>.  If latest/previous_init are given, add to those
+    stats rather than compute them from scratch.
+  """
+  if 'results' not in stats:
+    return None
+  result = {
+      'latest' : latest_init if latest_init else default_stats(),
+      'previous': previous_init if previous_init else default_stats(),
+  }
+  for dataset, name in zip(stats['results'], ['latest', 'previous']):
+    result[name]['begin'] = min(
+        date_from_timestamp(dataset['begin']),
+        result[name].get('begin', datetime.datetime.now()))
+    result[name]['end'] = max(date_from_timestamp(dataset['end']),
+                              result[name]['end'])
+    re_trybot_pass_count = re.compile('^trybot-(.+)-pass-count$')
+    re_trybot_false_reject_count = re.compile(
+        '^trybot-(.+)-false-reject-count$')
+    assert 'jobs' in result[name] and isinstance(result[name]['jobs'], dict)
+    for data in dataset['stats']:
+      if data['type'] == 'count':
+        result[name][data['name']] = data['count']
+        match_pass = re_trybot_pass_count.match(data['name'])
+        match_false_reject = re_trybot_false_reject_count.match(data['name'])
+        if match_pass:
+          job_name = match_pass.group(1)
+          result[name]['jobs'].setdefault(job_name, {
+              'pass-count': 0,
+              'false-reject-count': 0,
+          })
+          result[name]['jobs'][job_name]['pass-count'] += data['count']
+          logging.debug('Job %s passed %d times. Jobs: %r',
+                        job_name, data['count'], result[name]['jobs'])
+        if match_false_reject:
+          job_name = match_false_reject.group(1)
+          result[name]['jobs'].setdefault(job_name, {
+              'pass-count': 0,
+              'false-reject-count': 0,
+          })
+          result[name]['jobs'][job_name]['false-reject-count'] += data['count']
+          logging.debug('Job %s flakily failed %d times',
+                        job_name, data['count'])
+      else:
+        assert data['type'] == 'list'
+        result[name][data['name']] = {
+            '10': data['percentile_10'],
+            '25': data['percentile_25'],
+            '50': data['percentile_50'],
+            '75': data['percentile_75'],
+            '90': data['percentile_90'],
+            '95': data['percentile_95'],
+            '99': data['percentile_99'],
+            'min': data['min'],
+            'max': data['max'],
+            'mean': data['mean'],
+            'size': data['sample_size'],
+        }
+  return result
+
+
+def derive_list_stats(series):
+  if not series:
+    series = [0]
+  return {
+      '10': numpy.percentile(series, 10),
+      '25': numpy.percentile(series, 25),
+      '50': numpy.percentile(series, 50),
+      '75': numpy.percentile(series, 75),
+      '90': numpy.percentile(series, 90),
+      '95': numpy.percentile(series, 95),
+      '99': numpy.percentile(series, 99),
+      'min': min(series),
+      'max': max(series),
+      'mean': numpy.mean(series),
+      'size': len(series),
+  }
+
+
+def sort_by_count(elements):
+  return sorted(elements, key=lambda p: p['count'], reverse=True)
+
+
+def stats_by_count_entry(patch_stats, name, patch, reasons):
+  entry = {
+      'count': patch_stats[name],
+      'patch_id': patch,
+      'failed-jobs-details': patch_stats['failed-jobs-details']
+  }
+  for n in reasons:
+    if n in patch_stats:
+      entry[n] = patch_stats[n]
+      assert type(entry[n]) is int, 'Bad type in %s[%s]: %r\nEntry=%r' % (
+        patch, n, entry[n], entry)
+  return entry
+
+
+# "Dangerous default value []": pylint: disable=W0102
+def stats_by_count(patch_stats, name, reasons=[]):
+  return sort_by_count([
+      stats_by_count_entry(patch_stats[p], name, p, reasons)
+      for p in patch_stats if patch_stats[p].get(name)])
+
+
+def _derive_stats_from_patch_stats(stats):
+  patch_stats = stats['patch_stats']
+  stats['attempt-count'] = sum(
+      patch_stats[p]['attempts'] for p in patch_stats)
+  stats['patchset-false-reject-count'] = sum(
+      patch_stats[p]['false-rejections'] for p in patch_stats)
+  stats['attempt-reject-count'] = sum(
+      patch_stats[p]['rejections'] for p in patch_stats)
+  stats['rejected-patches'] = set(
+      p for p in patch_stats if not patch_stats[p]['committed'])
+  stats['false-rejections'] = stats_by_count(
+      patch_stats, 'false-rejections', REASONS)
+  stats['rejections'] = stats_by_count(patch_stats, 'rejections', REASONS)
+  for r in REASONS:
+    stats[r] = stats_by_count(patch_stats, r, set(REASONS) - set([r]))
+
+  stats['patchset-commit-count'] = len([
+      p for p in patch_stats if patch_stats[p]['committed']])
+  stats['patchset-total-commit-queue-durations'] = derive_list_stats([
+      patch_stats[p]['patchset-duration-wallclock'] for p in patch_stats])
+  stats['patchset-durations'] = derive_list_stats([
+      patch_stats[p]['patchset-duration'] for p in patch_stats])
+  stats['patchset-committed-durations'] = derive_list_stats([
+      patch_stats[p]['patchset-duration'] for p in patch_stats
+      if patch_stats[p]['committed']])
+  stats['patchset-attempts'] = derive_list_stats([
+      patch_stats[p]['attempts'] for p in patch_stats])
+  stats['patchset-committed-attempts'] = derive_list_stats([
+      patch_stats[p]['attempts'] for p in patch_stats
+      if patch_stats[p]['committed']])
+
+
+def derive_stats(args, begin_date, init_stats=None):
+  """Process raw CQ updates log and derive stats.
+
+  Fetches raw CQ events and returns the same format as organize_stats().
+  If ``init_stats`` are given, preserve the jobs stats and replace the
+  other stats.
+  """
+  stats = init_stats or default_stats()
+  filters = ['project=%s' % args.project, 'action=patch_stop']
+  end_date = begin_date + datetime.timedelta(minutes=INTERVALS[args.range])
+  results = fetch_cq_logs(begin_date, end_date, filters=filters)
+  if not results:
+    return stats
+
+  stats['begin'] = date_from_timestamp(results[-1]['timestamp'])
+  stats['end'] = date_from_timestamp(results[0]['timestamp'])
+  # Create map issue:patchset -> #attempts
+  patches, issues = set(), set()
+  for reason in results:
+    issues.add(reason['fields']['issue'])
+    patches.add((reason['fields']['issue'], reason['fields']['patchset']))
+  stats['issue-count'] = len(issues)
+  stats['patchset-count'] = len(patches)
+  patch_stats = {}
+  # Fetch and process each patchset log
+  def get_patch_stats(patch_id):
+    return derive_patch_stats(end_date, patch_id)
+
+  if args.seq or not args.thread_pool:
+    iterable = map(get_patch_stats, patches)
+  else:
+    pool = ThreadPool(min(args.thread_pool, len(patches)))
+    iterable = pool.imap_unordered(get_patch_stats, patches)
+  for patch_id, pstats in iterable:
+    patch_stats[patch_id] = pstats
+
+  stats['patch_stats'] = patch_stats
+  _derive_stats_from_patch_stats(stats)
+  return stats
+
+
+def patch_url(patch_id):
+  return '%s/patch-status/%s/%s' % ((STATS_URL,) + patch_id)
+
+
+def parse_json(obj, return_type=None):
+  """Attempt to interpret a string as JSON.
+
+  Guarantee the return type if given, pass through otherwise.
+  """
+  result = obj
+  if type(obj) in [str, unicode]:
+    try:
+      result = json.loads(obj)
+    except ValueError as e:
+      logging.error('Could not decode json in "%s": %s', obj, e)
+  # If the type is wrong, return an empty object of the correct type.
+  # In most cases, casting to the required type will not work anyway
+  # (e.g. list to dict).
+  if return_type and type(result) is not return_type:
+    result = return_type()
+  return result
+
+
+def parse_failing_tryjobs(message):
+  """Parse the message to extract failing try jobs."""
+  builders = []
+  msg_lines = message.splitlines()
+  for line in msg_lines[1:]:
+    words = line.split(None, 1)
+    if not words:
+      continue
+    builder = words[0]
+    builders.append(builder)
+  return builders
+
+
+def derive_patch_stats(end_date, patch_id):
+  """``patch_id`` is a tuple (issue, patchset)."""
+  results = fetch_cq_logs(end_date=end_date, filters=[
+      'issue=%s' % patch_id[0], 'patchset=%s' % patch_id[1]])
+  # The results should already ordered, but sort it again just to be sure.
+  results = sorted(results, key=lambda r: r['timestamp'], reverse=True)
+  logging.debug('derive_patch_stats(%r): fetched %d entries.',
+                patch_id, len(results))
+  # Group by attempts
+  attempts = []
+
+  def new_attempt():
+    attempt_empty = {
+        'id': 0,
+        'begin': 0.0,
+        'end': 0.0,
+        'duration': 0.0,
+        'actions': [],
+        'committed': False,
+        'reason': {},
+    }
+    for reason in REASONS:
+      attempt_empty[reason] = False
+    return attempt_empty
+
+  def add_attempt(attempt, counter):
+    """Create a new attempt from accumulated actions."""
+    assert attempt['actions']
+    attempt['id'] = counter
+    attempt['duration'] = attempt['end'] - attempt['begin']
+    known_reasons = [r for r in KNOWN_REASONS if attempt[r]]
+    if not attempt['committed'] and not known_reasons:
+      attempt['failed-unknown'] = True
+    logging.debug(
+        'add_attempt: #%d (%s)',
+        attempt['id'],
+        ', '.join([r for r in REASONS if attempt[r]]))
+    attempts.append(attempt)
+
+  # An attempt is a set of actions between patch_start and patch_stop
+  # actions. Repeated patch_start / patch_stop actions are ignored.
+  attempt = new_attempt()
+  failing_builders = {}
+  state = 'stop'
+  attempt_counter = 0
+  for result in reversed(results):
+    action = result['fields'].get('action')
+    if state == 'stop':
+      if action == 'patch_start':
+        state = 'start'
+        attempt['begin'] = result['timestamp']
+    if state != 'start':
+      continue
+    attempt['actions'].append(result)
+    if action == 'patch_stop':
+      attempt['end'] = result['timestamp']
+      message = result['fields'].get('message', '')
+      if 'CQ bit was unchecked on CL' in message:
+        attempt['manual-cancel'] = True
+      if 'No LGTM' in message:
+        attempt['missing-lgtm'] = True
+      if 'A disapproval has been posted' in message:
+        attempt['not-lgtm'] = True
+      if 'Transient error: Invalid delimiter' in message:
+        attempt['invalid-delimiter'] = True
+      if 'Failed to commit' in message:
+        attempt['failed-commit'] = True
+      if('Failed to apply patch' in message or
+         'Failed to apply the patch' in message):
+        attempt['failed-patch'] = True
+      if 'Presubmit check' in message:
+        attempt['failed-presubmit-check'] = True
+      if 'Try jobs failed' in message:
+        if 'presubmit' in message:
+          attempt['failed-presubmit-bot'] = True
+        else:
+          attempt['failed-jobs'] = message
+          builders = parse_failing_tryjobs(message)
+          for b in builders:
+            failing_builders.setdefault(b, 0)
+            failing_builders[b] += 1
+      if 'Exceeded time limit waiting for builds to trigger' in message:
+        attempt['failed-to-trigger'] = True
+      attempt_counter += 1
+      add_attempt(attempt, attempt_counter)
+      attempt = new_attempt()
+      state = 'stop'
+      continue
+    if action == 'patch_committed':
+      attempt['committed'] = True
+    # TODO(sergeyberezin): enable this after this action is stable in CQ.
+    if action == 'patch_failed':
+      attempt['reason'] = parse_json(
+          result['fields'].get('reason', {}), return_type=dict)
+      logging.info('Attempt reason: %r', attempt['reason'])
+      if attempt['reason'].get('fail_type') == 'reviewer_lgtm':
+        attempt['missing-lgtm'] = True
+      if attempt['reason'].get('fail_type') == 'commit':
+        attempt['failed-commit'] = True
+      if attempt['reason'].get('fail_type') == 'simple try job':
+        failed_jobs = parse_json(attempt['reason'].get(
+            'fail_details', [('unknown_master', 'unknown_bot')]))
+        # Remove presubmit bot - it's accounted separately.
+        failed_jobs = [j for j in failed_jobs if 'presubmit' in j[1]]
+        attempt['failed-jobs'] = failed_jobs
+
+  stats = {}
+  committed_set = set(a['id'] for a in attempts if a['committed'])
+  stats['committed'] = len(committed_set)
+  stats['attempts'] = len(attempts)
+  stats['rejections'] = stats['attempts'] - stats['committed']
+
+  logging.info('derive_patch_stats: %s has %d attempts, committed=%d',
+               patch_url(patch_id), len(attempts), stats['committed'])
+
+  valid_reasons_set = set()
+  for reason in VALID_REASONS:
+    s = set(a['id'] for a in attempts if a[reason])
+    stats[reason] = len(s)
+    valid_reasons_set.update(s)
+  for reason in set(REASONS) - set(VALID_REASONS):
+    stats[reason] = len(set(a['id'] for a in attempts if a[reason]))
+
+  # Populate failed builders.
+  stats['failed-jobs-details'] = failing_builders
+
+  stats['false-rejections'] = 0
+  if stats['committed']:
+    stats['false-rejections'] = len(
+        set(a['id'] for a in attempts) - committed_set - valid_reasons_set)
+  # Sum of attempt duration.
+  stats['patchset-duration'] = sum(a['duration'] for a in attempts)
+  if attempts:
+    stats['patchset-duration-wallclock'] = (
+        attempts[-1]['end'] - attempts[0]['begin'])
+  else:
+    stats['patchset-duration-wallclock'] = 0.0
+  return patch_id, stats
+
+
+def derive_tree_stats(project, start_date, end_date):
+  """Given a list of tree status events, derive tree closure stats."""
+  # Fetch one more event right before the range, so we know the
+  # initial tree status.
+  status = (fetch_tree_status(project, end_date=start_date, limit=1) +
+            fetch_tree_status(project, end_date, start_date))
+  stats = {'open': 0.0, 'total': (end_date - start_date).total_seconds()}
+  if not status:
+    return stats
+
+  logging.debug('Tree status:\n%s', '\n'.join(['  %r' % e for e in status]))
+
+  is_open = status[0]['open']
+  curr_date = start_date
+  for event in status[1:]:
+    delta = event['date'] - curr_date
+    if is_open and not event['open']:
+      stats['open'] += delta.total_seconds()
+      logging.debug('Tree was open from %s to %s for %s (total of %s)',
+                    curr_date, event['date'],
+                    delta, datetime.timedelta(seconds=stats['open']))
+    if not is_open:
+      curr_date = event['date']
+    is_open = event['open']
+
+  # Account for the remaining time after the last event.
+  if is_open:
+    delta = end_date - curr_date
+    stats['open'] += delta.total_seconds()
+    logging.debug('Tree was open from %s to %s for %s (total of %s)',
+                  curr_date, end_date,
+                  delta, datetime.timedelta(seconds=stats['open']))
+  return stats
+
+
+def derive_log_stats(log_data, bots):
+  # Calculate stats.
+  cq_commits = [v for v in log_data if v['commit-bot']]
+  users = {}
+  for commit in cq_commits:
+    users[commit['author']] = users.get(commit['author'], 0) + 1
+  committers = {}
+  manual_committers = {}
+  bot_committers = {}
+  bot_manual_committers = {}
+  for commit in log_data:
+    committers[commit['author']] = committers.get(commit['author'], 0) + 1
+    if not commit['commit-bot']:
+      manual_committers[commit['author']] = manual_committers.get(
+          commit['author'], 0) + 1
+    if commit['author'] in bots:
+      bot_committers[commit['author']] = bot_committers.get(
+          commit['author'], 0) + 1
+      if not commit['commit-bot']:
+        bot_manual_committers[commit['author']] = bot_manual_committers.get(
+            commit['author'], 0) + 1
+
+  stats = {}
+  stats['cq_commits'] = len(cq_commits)
+  stats['total_commits'] = len(log_data)
+  stats['users'] = len(users)
+  stats['committers'] = len(committers)
+  stats['manual_committers'] = len(manual_committers)
+  stats['manual_commits'] = sum(x for x in manual_committers.itervalues())
+  stats['bot_committers'] = len(bot_committers)
+  stats['bot_commits'] = sum(x for x in bot_committers.itervalues())
+  stats['bot_manual_commits'] = sum(
+      x for x in bot_manual_committers.itervalues())
+  stats['manual_only_committers'] = {
+      a: c for a, c in committers.iteritems()
+      if c == manual_committers.get(a, 0)}
+  return stats
+
+def derive_git_stats(project, start_date, end_date, bots):
+  log_data = fetch_git_logs(PROJECTS[project]['repo'], start_date, end_date)
+  return derive_log_stats(log_data, bots)
+
+
+def derive_svn_stats(project, start_date, end_date, bots):
+  log_data = fetch_svn_logs(PROJECTS[project]['repo'], start_date, end_date)
+  return derive_log_stats(log_data, bots)
+
+
+def percentage_tuple(data, total):
+  num_data = data if isinstance(data, numbers.Number) else len(data)
+  num_total = total if isinstance(total, numbers.Number) else len(total)
+  percent = 100. * num_data / num_total if num_total else 0.
+  return num_data, num_total, percent
+
+
+def percentage(data, total):
+  return percentage_tuple(data, total)[2]
+
+
+def round_timedelta(seconds):
+  # We never care about the milliseconds when printing timedeltas:
+  return datetime.timedelta(seconds=round(seconds))
+
+
+def output(fmt='', *args):
+  """An equivalent of print to mock out in testing."""
+  print fmt % args
+
+
+def print_attempt_counts(stats, name, message, item_name='',
+                         details=False, committed=None, indent=0,
+                         print_zero=False):
+  """Print a summary of a ``name`` slice of attempts.
+
+  |committed|: None=print all, True=only committed patches, False=only
+   rejected patches.
+
+  |print_zero|: print stats even if no attempts match."""
+  if not item_name:
+    item_name = message
+  patches = [
+      p for p in stats[name]
+      if committed is None or
+      bool(stats['patch_stats'][p['patch_id']]['committed']) is committed]
+  count = sum(p['count'] for p in patches)
+  if not print_zero and not count:
+    return
+
+  failing_builders = {}
+  for p in patches:
+    for b, cnt in p['failed-jobs-details'].iteritems():
+      failing_builders.setdefault(b, {})
+      failing_builders[b][p['patch_id']] = cnt
+
+  indent_str = ''.join(' ' for _ in range(indent))
+  if message.startswith('failed jobs'):
+    output(
+        '%s%4d attempt%s (%.1f%% of %d attempts) %s: %d in %d%s patches',
+        indent_str, count, ' ' if count == 1 else 's',
+        percentage(count, stats['attempt-count']),
+        stats['attempt-count'],
+        message,
+        sum(sum(d.values()) for d in failing_builders.values()),
+        len(patches),
+        {True: ' committed', False: ' uncommitted'}.get(committed, ''))
+  else:
+    output(
+        '%s%4d attempt%s (%.1f%% of %d attempts) %s in %d%s patches',
+        indent_str, count, ' ' if count == 1 else 's',
+        percentage(count, stats['attempt-count']),
+        stats['attempt-count'],
+        message,
+        len(patches),
+        {True: ' committed', False: ' uncommitted'}.get(committed, ''))
+  if details:
+    lines = []
+    for p in patches:
+      line = '      %d %s %s'  % (
+          p['count'], item_name, patch_url(p['patch_id']))
+      causes = ['%d %s' % (p['failed-jobs-details'][k], k)
+                for k in p['failed-jobs-details']]
+      line += ' (%s)' % ', '.join(causes)
+      lines.append(line)
+    output('\n'.join(lines))
+    output()
+
+
+def print_duration(name, args, latest, previous, print_name=None):
+  if not print_name:
+    print_name = name.capitalize()
+  cq_only = round_timedelta(latest['patchset-durations'][name])
+  wallclock = round_timedelta(
+      latest['patchset-total-commit-queue-durations'][name])
+  prev_cq_only = 'unknown'
+  prev_cq_only_s = 'unknown'
+  prev_wallclock = 'unknown'
+  prev_wallclock_s = 'unknown'
+  if previous:
+    prev_cq_only = round_timedelta(previous['patchset-durations'][name])
+    prev_cq_only_s = int(prev_cq_only.total_seconds() / 60)
+    prev_wallclock = round_timedelta(
+        previous['patchset-total-commit-queue-durations'][name])
+    prev_wallclock_s = int(prev_wallclock.total_seconds() / 60)
+  output('\n%s duration in CQ trying a patch:', print_name)
+  output(
+      '  wallclock:       %8s (%3d min). Prev. %s: %8s (%3s min).',
+      wallclock, round(wallclock.total_seconds() / 60.0), args.range,
+      prev_wallclock, prev_wallclock_s)
+  output(
+      '  sum of attempts: %8s (%3d min). Prev. %s: %8s (%3s min).',
+      cq_only, round(cq_only.total_seconds() / 60.0), args.range,
+      prev_cq_only, prev_cq_only_s)
+
+
+def print_usage(args, latest, previous):
+  if not latest['usage']:
+    return
+  output()
+  output(
+      'CQ users:      %6d out of %6d total committers %6.2f%%',
+      latest['usage']['users'], latest['usage']['committers'],
+      percentage(latest['usage']['users'], latest['usage']['committers']))
+  fmt_str = (
+      '  Committed    %6d out of %6d commits          %6.2f%%. '
+      'Prev. %s: %6.2f%%.')
+  data = percentage_tuple(latest['usage']['cq_commits'],
+                          latest['usage']['total_commits'])
+  data += (args.range, percentage(previous['usage']['cq_commits'],
+                                  previous['usage']['total_commits']))
+  if latest['usage']['bot_manual_commits']:
+    fmt_str += ' (%6.2f%% by humans)'
+    data += (percentage(latest['usage']['cq_commits'],
+                        latest['usage']['total_commits'] -
+                        latest['usage']['bot_manual_commits']),)
+  output(fmt_str, *data)
+
+  output()
+  output('Bots:                %6d out of %6d total committers %6.2f%%',
+         *percentage_tuple(latest['usage']['bot_committers'],
+                           latest['usage']['committers']))
+  output('  Committed by CQ    %6d out of %6d commits          %6.2f%%',
+         *percentage_tuple(latest['usage']['bot_commits'],
+                           latest['usage']['total_commits']))
+  output('  Committed directly %6d out of %6d commits          %6.2f%%',
+         *percentage_tuple(latest['usage']['bot_manual_commits'],
+                           latest['usage']['total_commits']))
+  output()
+  output('Manual committers: %6d out of all %6d users   %6.2f%%',
+         *percentage_tuple(latest['usage']['manual_committers'],
+                           latest['usage']['committers']))
+  output('  Committed        %6d out of     %6d commits %6.2f%%',
+         *percentage_tuple(latest['usage']['manual_commits'],
+                           latest['usage']['total_commits']))
+
+
+def print_tree_status(args, latest, previous):
+  output()
+  output(
+      'Total time tree open: %.1f hours of %.1f hours (%.2f%%). '
+      'Prev. %s: %.2f%%.',
+      latest['tree']['open'] / 3600.0,
+      latest['tree']['total'] / 3600.0,
+      percentage(latest['tree']['open'], latest['tree']['total']),
+      args.range,
+      percentage(previous['tree']['open'], previous['tree']['total']))
+
+
+def print_stats(args, stats):
+  latest = stats.get('latest')
+  previous = stats.get('previous')
+  if not latest:
+    output('No stats to display.')
+    return
+  if not previous:
+    output('No previous %s stats loaded.', args.range)
+    return
+  output('Statistics for project %s', args.project)
+  if latest['begin'] > latest['end']:
+    output('  No stats since %s', args.date)
+    return
+
+  output('from %s till %s (local time).',
+         latest['begin'], latest['end'])
+
+  print_usage(args, latest, previous)
+  print_tree_status(args, latest, previous)
+
+  output()
+  output(
+      '%4d issues (%d patches) were tried by CQ, '
+      'resulting in %d attempts.',
+      latest['issue-count'], latest['patchset-count'], latest['attempt-count'])
+  output(
+      '%4d patches (%.1f%% of tried patches, %.1f%% of attempts) '
+      'were committed by CQ,',
+      latest['patchset-commit-count'],
+      percentage(latest['patchset-commit-count'], latest['patchset-count']),
+      percentage(latest['patchset-commit-count'], latest['attempt-count']))
+
+
+  output()
+  output('Rejections:')
+  print_attempt_counts(latest, 'rejections', 'were unsuccessful',
+                       item_name='failures',
+                       committed=False)
+  output('  This includes:')
+  for reason in REASONS:
+    print_attempt_counts(latest, reason, REASONS[reason]['message'], indent=2,
+                         details=args.list_rejections,
+                         item_name=REASONS[reason]['item'], committed=False)
+
+  # TODO(sergeyberezin): add gave up count (committed manually after trying CQ).
+  # TODO(sergeyberezin): add count of NOTRY=true (if possible).
+
+  output()
+  output('False Rejections:')
+  if args.use_logs:
+    print_attempt_counts(latest, 'false-rejections', 'were false rejections',
+                         item_name='flakes', committed=True)
+  else:
+    output(
+        '  %4d attempts (%.1f%% of %d attempts) were false rejections',
+        latest['attempt-false-reject-count'],
+        percentage(latest['attempt-false-reject-count'],
+                   latest['attempt-count']),
+        latest['attempt-count'])
+
+  output('  False rejections include:')
+  for reason in FLAKY_REASONS.keys() + ['failed-unknown']:
+    print_attempt_counts(latest, reason, REASONS[reason]['message'], indent=2,
+                         item_name=REASONS[reason]['item'], committed=True,
+                         details=args.list_false_rejections)
+
+  output('  Other rejections in committed patches for valid reasons:')
+  for reason in VALID_REASONS.keys():
+    print_attempt_counts(latest, reason, REASONS[reason]['message'], indent=2,
+                         item_name=REASONS[reason]['item'], committed=True,
+                         details=args.list_false_rejections)
+
+  print_duration('mean', args, latest, previous)
+  print_duration('50', args, latest, previous, 'Median')
+
+  output()
+  output('Patches which eventually land percentiles:')
+  for p in ['10', '25', '50', '75', '90', '95', '99']:
+    output('%s: %4.1f hrs, %2d attempts',
+           p, latest['patchset-committed-durations'][p] / 3600.0,
+           latest['patchset-committed-attempts'][p])
+
+  # TODO(sergeyberezin): add total try jobs / by CQ / unknown. Get it from CBE.
+  # TODO(sergeyberezin): recompute bot flakiness from CBE. CQ does not
+  # have enough info.
+  output()
+  output('Top flaky builders (which fail and succeed in the same patch):')
+
+  logging.debug('Found %d jobs', len(latest['jobs'].keys()))
+
+  def flakiness(stats, job):
+    passes = stats['jobs'][job]['pass-count']
+    failures = stats['jobs'][job]['false-reject-count']
+    return percentage(failures, passes + failures)
+
+  jobs = sorted(latest['jobs'].iterkeys(), key=lambda j: flakiness(latest, j),
+                reverse=True)
+  output('%-40s %-15s %-15s %-15s',
+         'Builder Name', 'Succeeded', 'Flaky Failures', 'Flakiness (%)')
+  for job in jobs:
+    passes = latest['jobs'][job]['pass-count']
+    failures = latest['jobs'][job]['false-reject-count']
+    output('%-40s %-15s %-15s %-15s',
+           job, '%5d' % passes, '%5d' % failures,
+           '%6.2f%%' % flakiness(latest, job))
+
+
+def acquire_stats(args):
+  stats = {}
+  logging.info('Acquiring stats for project %s for a %s of %s using %s',
+               args.project, args.range, args.date,
+               'logs' if args.use_logs else 'cache')
+  end_date = args.date + datetime.timedelta(minutes=INTERVALS[args.range])
+  prev_date = args.date - datetime.timedelta(minutes=INTERVALS[args.range])
+  if args.use_logs:
+    init_stats = {'latest': default_stats(), 'previous': default_stats()}
+    assert args.date
+    # For weekly stats, collect job flakiness from daily cached stats.
+    if args.range == 'week':
+      for day in range(7):
+        d = args.date + datetime.timedelta(minutes=INTERVALS['day']*day)
+        raw_stats = fetch_stats(args, d, 'day')
+        init_stats = organize_stats(raw_stats, latest_init=init_stats['latest'])
+    elif args.range == 'day':
+      for hour in range(24):
+        d = args.date + datetime.timedelta(minutes=INTERVALS['hour']*hour)
+        raw_stats = fetch_stats(args, d, 'hour')
+        init_stats = organize_stats(raw_stats, latest_init=init_stats['latest'])
+    else:
+      init_stats = organize_stats(fetch_stats(args))
+    stats['latest'] = derive_stats(
+        args, args.date, init_stats=init_stats['latest'])
+    stats['previous'] = derive_stats(args, prev_date)
+  else:
+    stats = organize_stats(fetch_stats(args))
+
+  stats['latest']['tree'] = derive_tree_stats(args.project, args.date, end_date)
+  stats['previous']['tree'] = derive_tree_stats(
+      args.project, prev_date, args.date)
+
+  if PROJECTS[args.project]['type'] == 'git':
+    stats['latest']['usage'] = derive_git_stats(
+        args.project, args.date, end_date, args.bots)
+    stats['previous']['usage'] = derive_git_stats(
+        args.project, prev_date, args.date, args.bots)
+  else:
+    stats['latest']['usage'] = derive_svn_stats(
+        args.project, args.date, end_date, args.bots)
+    stats['previous']['usage'] = derive_svn_stats(
+        args.project, prev_date, args.date, args.bots)
+
+  return stats
+
+def main():
+  args = parse_args()
+  logger = logging.getLogger()
+  # TODO(sergeyberezin): how do I derive local timezone string?
+  # Need to be able to pass dateutil.tz.tzlocal() directly.
+  infra.libs.logs.process_argparse_options(args, logger)
+  stats = acquire_stats(args)
+  print_stats(args, stats)
+
+
+if __name__ == '__main__':
+  sys.exit(main())