Add PRESUBMIT check to enforce the rule of tools/perf/contrib/ directory

tools/perf/PRESUBMIT.py

Index: tools/perf/PRESUBMIT.py
diff --git a/tools/perf/PRESUBMIT.py b/tools/perf/PRESUBMIT.py
index 5c02969c992563f15e961787aadec1c855f7049b..9094e09f371409cd30895cfe164c6ffd3e03f314 100644
--- a/tools/perf/PRESUBMIT.py
+++ b/tools/perf/PRESUBMIT.py
@@ -19,6 +19,7 @@ def _CommonChecks(input_api, output_api):
   results.extend(_CheckWprShaFiles(input_api, output_api))
   results.extend(_CheckJson(input_api, output_api))
   results.extend(_CheckPerfJsonUpToDate(input_api, output_api))
+  results.extend(_CheckContribDir(input_api, output_api))
   results.extend(input_api.RunTests(input_api.canned_checks.GetPylint(
       input_api, output_api, extra_paths_list=_GetPathsToPrepend(input_api),
       pylintrc='pylintrc')))
@@ -49,6 +50,59 @@ def _RunArgs(args, input_api):
   return (out, p.returncode)
 
 
+def _CheckOwnershipForContribSubDir(sub_dir, input_api, output_api):
+  results = []
+  owner_file = input_api.os_path.join(sub_dir, 'OWNERS')
+  if not input_api.os_path.isfile(owner_file):
+    results.append(output_api.PresubmitError(
+        '%s must have an OWNERS file' % sub_dir))
+  else:
+    owners = []
+    with open(owner_file) as f:
+      for line in f:
+        if not line.strip().startswith('#'):
+          owners.append(line)
+    if len(owners) < 2:
+      results.append(output_api.PresubmitError(
+          '%s must have at least 2 owners' % owner_file))
+  return results

[sullivan, 2017/05/10 14:59:19]

Just wanted to check there's not already an API in presubmit for listing owners?

[nednguyen, 2017/05/10 22:07:37]

I look around and there is no API there that support this.

+
+
+def _CheckContribDir(input_api, output_api):

[charliea (OOO until 10-5), 2017/05/10 15:52:29]

(I'm not super familiar with how PRESUBMIT.py works, so I apologize if this is a
dumb question...)

Could we just put this in a PRESUBMIT.py in the contrib/ directory, given that
it only applies to that directory?

I'm guessing that the actual presubmit interface revolves around
CheckChangeOnUpload and CheckChangeOnCommit, both of which have a pretty simple
interface, so it's not like we're taking advantage of a bunch of common code by
putting it in this file.

+  """ Check to make sure that:
+    1) tools/perf/contrib/ contains only directories, except __init__.py file
+    and README.md file
+    2) Every subdirectory in tools/perf/contrib/ must have an OWNERS file with
+    at least two OWNERS.
+  """
+  results = []
+  contrib_dir = input_api.os_path.abspath(
+      input_api.os_path.join(input_api.PresubmitLocalPath(), 'contrib'))
+  init = input_api.os_path.join(contrib_dir, '__init__.py')
+  readme = input_api.os_path.join(contrib_dir, 'README.md')
+
+  invalid_contrib_files = []
+  for f in input_api.AffectedFiles(include_deletes=False):
+    file_path = f.AbsoluteLocalPath()
+    if (input_api.os_path.dirname(file_path) == contrib_dir and
+        not file_path in (init, readme)):
+      invalid_contrib_files.append(file_path)
+
+  for f in input_api.os_listdir(contrib_dir):
+    path = input_api.os_path.join(contrib_dir, f)
+    if input_api.os_path.isdir(path):
+      results.extend(
+          _CheckOwnershipForContribSubDir(path, input_api, output_api))
+
+  if invalid_contrib_files:
+    results.append(output_api.PresubmitError(
+        'You cannot add files to top level of contrib directory. '
+        'Please moves these files to a sub directory:\n %s' %
+        '\n'.join(invalid_contrib_files)))
+  return results
+
+
+
 def _CheckPerfJsonUpToDate(input_api, output_api):
   results = []
   perf_dir = input_api.PresubmitLocalPath()