add 'top list' command to summarize the top contributors to a set of inputs

Change-Id: Ie575d79be9cd6e47f3296815cbc9182776f86c1c
Signed-off-by: Doug Hellmann <doug@doughellmann.com>

goal_tools/who_helped/top.py

@@ -0,0 +1,64 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import collections
+import csv
+import itertools
+import logging
+
+from cliff import lister
+
+LOG = logging.getLogger(__name__)
+
+
+class TopN(lister.Lister):
+    """Report about the top N contributors.
+
+    Report how many times the top N contributors appear in all of the
+    input files.
+
+    """
+
+    def get_parser(self, prog_name):
+        parser = super().get_parser(prog_name)
+        parser.add_argument(
+            '--number', '-N',
+            default=10,
+            help='how many contributors to pull from each file',
+        )
+        parser.add_argument(
+            'report_file',
+            nargs='+',
+            help='name(s) of file(s) containing contribution summaries',
+        )
+        return parser
+
+    def take_action(self, parsed_args):
+
+        count = collections.Counter()
+
+        for filename in parsed_args.report_file:
+            LOG.debug('reading %s', filename)
+
+            with open(filename, 'r', encoding='utf-8') as f:
+                reader = (
+                    row
+                    for row in csv.DictReader(f)
+                    if not row['Name'].endswith('Bot')
+                )
+                count.update(
+                    row['Name']
+                    for row in itertools.islice(reader, parsed_args.number)
+                )
+
+        return (('Name', 'Appearances'),
+                sorted(count.items()))

setup.cfg

@@ -37,6 +37,7 @@ who_helped =
 	cache remove = goal_tools.who_helped.cache:CacheRemove
 	cache show = goal_tools.who_helped.cache:CacheShow
 	review show = goal_tools.who_helped.review:ReviewShow
+	top list = goal_tools.who_helped.top:TopN
 
 
 [wheel]