rebaseline_server: create ImagePairSet-- holds a number of ImagePairs to examine

gm/rebaseline_server/imagepair.py

Index: gm/rebaseline_server/imagepair.py
diff --git a/gm/rebaseline_server/imagepair.py b/gm/rebaseline_server/imagepair.py
index 1c71bd989caf436c097af45ac2237744d81916af..bba36fa8c4b4e47ab8101e1bcb580cba6095dee6 100644
--- a/gm/rebaseline_server/imagepair.py
+++ b/gm/rebaseline_server/imagepair.py
@@ -12,18 +12,16 @@ ImagePair class (see class docstring for details)
 import posixpath
 
 # Keys used within ImagePair dictionary representations.
-KEY_DIFFERENCE_DATA = 'differenceData'
-KEY_EXPECTATIONS_DATA = 'expectationsData'
-KEY_EXTRA_COLUMN_VALUES = 'extraColumnValues'
-KEY_IMAGE_A_URL = 'imageAUrl'
-KEY_IMAGE_B_URL = 'imageBUrl'
-KEY_IS_DIFFERENT = 'isDifferent'
+KEY__DIFFERENCE_DATA = 'differenceData'
+KEY__EXPECTATIONS_DATA = 'expectations'
+KEY__EXTRA_COLUMN_VALUES = 'extraColumns'
+KEY__IMAGE_A_URL = 'imageAUrl'
+KEY__IMAGE_B_URL = 'imageBUrl'
+KEY__IS_DIFFERENT = 'isDifferent'
 
 
 class ImagePair(object):
-  """
-  Describes a pair of images, along with optional metadata (pixel difference
-  metrics, whether to ignore mismatches, etc.)
+  """Describes a pair of images, pixel difference info, and optional metadata.
   """
 
   def __init__(self, image_diff_db,
@@ -63,21 +61,21 @@ class ImagePair(object):
           actual_image_locator=imageB_relative_url)
 
   def as_dict(self):
-    """
-    Return a dictionary describing this ImagePair, as needed when constructing
-    the JSON representation.  Uses the KEY_* constants as keys.
+    """Returns a dictionary describing this ImagePair.
+
+    Uses the KEY__* constants as keys.
     """
     asdict = {
-        KEY_IMAGE_A_URL: self.imageA_relative_url,
-        KEY_IMAGE_B_URL: self.imageB_relative_url,
+        KEY__IMAGE_A_URL: self.imageA_relative_url,
+        KEY__IMAGE_B_URL: self.imageB_relative_url,
     }
     if self.expectations_dict:
-      asdict[KEY_EXPECTATIONS_DATA] = self.expectations_dict
+      asdict[KEY__EXPECTATIONS_DATA] = self.expectations_dict
     if self.extra_columns_dict:
-      asdict[KEY_EXTRA_COLUMN_VALUES] = self.extra_columns_dict
+      asdict[KEY__EXTRA_COLUMN_VALUES] = self.extra_columns_dict
     if self.diff_record and (self.diff_record.get_num_pixels_differing() > 0):
-      asdict[KEY_IS_DIFFERENT] = True
-      asdict[KEY_DIFFERENCE_DATA] = self.diff_record.as_dict()
+      asdict[KEY__IS_DIFFERENT] = True
+      asdict[KEY__DIFFERENCE_DATA] = self.diff_record.as_dict()
     else:
-      asdict[KEY_IS_DIFFERENT] = False
+      asdict[KEY__IS_DIFFERENT] = False
     return asdict