Allow benchmarks to specify running multiple metrics.

tracing/bin/run_metric

 #!/usr/bin/env python
 # Copyright 2016 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.
 
 import argparse
 import json
 import os
 import sys
 
 sys.path.insert(1, os.path.join(os.path.dirname(__file__), '..'))
 from tracing.metrics import metric_runner
 from tracing.metrics import discover
 
 def Main(argv):
   all_metrics = discover.DiscoverMetrics(
       ['/tracing/metrics/all_metrics.html'])
   parser = argparse.ArgumentParser(
       description='Runs metrics on local traces')
-  parser.add_argument('metric_name',
-                      help=('The function name of a registered metric, NOT '
-                      'filename. Available metrics are: %s' %
+  parser.add_argument('metric', action='append', dest='metric_names',
+                      default=[],
+                      help=('Comma separated list of function names '
+                      'of registered metrics (not filenames.) '

[petrcermak, 2016/07/06 08:19:47]

nit: Lines 23-25 should be vertically aligned with "'Comma...", i.e.:

  parser.add_argument('metric', action='append', dest='metric_names',
                      default=[],
                      help=('Comma separated list of function names '
                            'of registered metrics (not filenames.) '
                            [...]

+                      'Available metrics are: %s' %
                       ', '.join(all_metrics)),
                       choices=all_metrics, metavar='metricName')
   parser.add_argument('trace_file_or_dir',
                       help='A trace file, or a dir containing trace files')
 
   args = parser.parse_args(argv[1:])
-  metric = args.metric_name
+  metrics = args.metric_names.split(',')
 
   if os.path.isdir(args.trace_file_or_dir):
     trace_dir = args.trace_file_or_dir
     traces = [os.path.join(trace_dir, trace) for trace in os.listdir(trace_dir)]
   else:
     traces = [args.trace_file_or_dir]
 
   results = {k: v.AsDict()
-      for k, v in metric_runner.RunMetricOnTraces(traces, metric).iteritems()}
+      for k, v in metric_runner.RunMetricOnTraces(traces, metrics).iteritems()}

[petrcermak, 2016/07/06 08:19:47]

nit: I think that "for" should be vertically aligned with "k:" according to the
Chromium Python style guide. Since that will make the secind line too long, I
suggest you break before "in" instead:

results = {k: v.AsDict() for k, v
           in metric_runner...}

 
   failures = []
   for trace in traces:
     failures.extend(results[trace].get('failures', []))
   if failures:
     print 'Running metric failed:'
     for failure in failures:
       print failure['stack']
   else:
     print json.dumps(results, indent=2, sort_keys=True, separators=(',', ': '))
 
 
 if __name__ == '__main__':
   sys.exit(Main(sys.argv))