rebaseline_server: allow JSON to control column filtering

gm/rebaseline_server/results.py

 #!/usr/bin/python
 
 """
 Copyright 2013 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 Repackage expected/actual GM results as needed by our HTML rebaseline viewer.
 """
 
 # System-level imports
 import fnmatch
 import os
 import re
 
+# Must fix up PYTHONPATH before importing from within Skia
+# pylint: disable=W0611
+import fix_pythonpath
+# pylint: enable=W0611
+
 # Imports from within Skia
-import fix_pythonpath  # must do this first
 import gm_json
 import imagepairset
 
 # Keys used to link an image to a particular GM test.
 # NOTE: Keep these in sync with static/constants.js
-VALUE__HEADER__SCHEMA_VERSION = 3
+VALUE__HEADER__SCHEMA_VERSION = 4
 KEY__EXPECTATIONS__BUGS = gm_json.JSONKEY_EXPECTEDRESULTS_BUGS
 KEY__EXPECTATIONS__IGNOREFAILURE = gm_json.JSONKEY_EXPECTEDRESULTS_IGNOREFAILURE
 KEY__EXPECTATIONS__REVIEWED = gm_json.JSONKEY_EXPECTEDRESULTS_REVIEWED
 KEY__EXTRACOLUMNS__BUILDER = 'builder'
 KEY__EXTRACOLUMNS__CONFIG = 'config'
 KEY__EXTRACOLUMNS__RESULT_TYPE = 'resultType'
 KEY__EXTRACOLUMNS__TEST = 'test'
 KEY__HEADER__DATAHASH = 'dataHash'
 KEY__HEADER__IS_EDITABLE = 'isEditable'
 KEY__HEADER__IS_EXPORTED = 'isExported'
@@ skipping 159 matching lines @@
       where each JSON dictionary was found).
 
     Raises:
       IOError if root does not refer to an existing directory
     """
     # I considered making this call _read_dicts_from_root(), but I decided
     # it was better to prune out the ignored builders within the os.walk().
     if not os.path.isdir(root):
       raise IOError('no directory found at path %s' % root)
     meta_dict = {}
-    for dirpath, dirnames, filenames in os.walk(root):
+    for dirpath, _, filenames in os.walk(root):
       for matching_filename in fnmatch.filter(filenames, pattern):
         builder = os.path.basename(dirpath)
         if self._ignore_builder(builder):
           continue
         full_path = os.path.join(dirpath, matching_filename)
         meta_dict[builder] = gm_json.LoadFromFile(full_path)
     return meta_dict
 
   def _read_dicts_from_root(self, root, pattern='*.json'):
     """Read all JSON dictionaries within a directory tree.
 
     Args:
       root: path to root of directory tree
       pattern: which files to read within root (fnmatch-style pattern)
 
     Returns:
       A meta-dictionary containing all the JSON dictionaries found within
       the directory tree, keyed by the pathname (relative to root) of each JSON
       dictionary.
 
     Raises:
       IOError if root does not refer to an existing directory
     """
     if not os.path.isdir(root):
       raise IOError('no directory found at path %s' % root)
     meta_dict = {}
-    for abs_dirpath, dirnames, filenames in os.walk(root):
+    for abs_dirpath, _, filenames in os.walk(root):
       rel_dirpath = os.path.relpath(abs_dirpath, root)
       for matching_filename in fnmatch.filter(filenames, pattern):
         abs_path = os.path.join(abs_dirpath, matching_filename)
         rel_path = os.path.join(rel_dirpath, matching_filename)
         meta_dict[rel_path] = gm_json.LoadFromFile(abs_path)
     return meta_dict
 
   @staticmethod
   def _read_noncomment_lines(path):
     """Return a list of all noncomment lines within a file.
@@ skipping 44 matching lines @@
 
     Output:
       {
         KEY_B1 : VALUE_B1,
         KEY_B2 : VALUE_B2,
       }
 
     If this would result in any repeated keys, it will raise an Exception.
     """
     output_dict = {}
-    for key, subdict in input_dict.iteritems():
+    for subdict in input_dict.values():
       for subdict_key, subdict_value in subdict.iteritems():
         if subdict_key in output_dict:
           raise Exception('duplicate key %s in combine_subdicts' % subdict_key)
         output_dict[subdict_key] = subdict_value
     return output_dict
 
   @staticmethod
   def get_multilevel(input_dict, *keys):
     """ Returns input_dict[key1][key2][...], or None if any key is not found.
     """
     for key in keys:
       if input_dict == None:
         return None
       input_dict = input_dict.get(key, None)
     return input_dict