Revert "delete old things!"

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
new file mode 100644
index 0000000000000000000000000000000000000000..e85c21948bfdc6ed683e4cd0977cc8f380d2f7ec
--- /dev/null
+++ b/gm/rebaseline_server/imagepair.py
@@ -0,0 +1,128 @@
+#!/usr/bin/python
+
+"""
+Copyright 2014 Google Inc.
+
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+
+ImagePair class (see class docstring for details)
+"""
+
+import posixpath
+
+
+# Keys used within ImagePair dictionary representations.
+# NOTE: Keep these in sync with static/constants.js
+KEY__IMAGEPAIRS__DIFFERENCES = 'differenceData'
+KEY__IMAGEPAIRS__EXPECTATIONS = 'expectations'
+KEY__IMAGEPAIRS__EXTRACOLUMNS = 'extraColumns'
+KEY__IMAGEPAIRS__IMAGE_A_URL = 'imageAUrl'
+KEY__IMAGEPAIRS__IMAGE_B_URL = 'imageBUrl'
+KEY__IMAGEPAIRS__IS_DIFFERENT = 'isDifferent'
+KEY__IMAGEPAIRS__SOURCE_JSON_FILE = 'sourceJsonFile'
+
+# If self._diff_record is set to this, we haven't asked ImageDiffDB for the
+# image diff details yet.
+_DIFF_RECORD_STILL_LOADING = 'still_loading'
+
+
+class ImagePair(object):
+  """Describes a pair of images, pixel difference info, and optional metadata.
+  """
+
+  def __init__(self, image_diff_db,
+               imageA_base_url, imageB_base_url,
+               imageA_relative_url, imageB_relative_url,
+               expectations=None, extra_columns=None, source_json_file=None,
+               download_all_images=False):
+    """
+    Args:
+      image_diff_db: ImageDiffDB instance we use to generate/store image diffs
+      imageA_base_url: string; base URL for image A
+      imageB_base_url: string; base URL for image B
+      imageA_relative_url: string; URL pointing at an image, relative to
+          imageA_base_url; or None, if this image is missing
+      imageB_relative_url: string; URL pointing at an image, relative to
+          imageB_base_url; or None, if this image is missing
+      expectations: optional dictionary containing expectations-specific
+          metadata (ignore-failure, bug numbers, etc.)
+      extra_columns: optional dictionary containing more metadata (test name,
+          builder name, etc.)
+      source_json_file: relative path of the JSON file where each image came
+          from; this will be the same for both imageA and imageB, within their
+          respective directories
+      download_all_images: if True, download any images associated with this
+          image pair, even if we don't need them to generate diffs
+          (imageA == imageB, or one of them is missing)
+    """
+    self._image_diff_db = image_diff_db
+    self.imageA_base_url = imageA_base_url
+    self.imageB_base_url = imageB_base_url
+    self.imageA_relative_url = imageA_relative_url
+    self.imageB_relative_url = imageB_relative_url
+    self.expectations_dict = expectations
+    self.extra_columns_dict = extra_columns
+    self.source_json_file = source_json_file
+    if not imageA_relative_url or not imageB_relative_url:
+      self._is_different = True
+      self._diff_record = None
+    elif imageA_relative_url == imageB_relative_url:
+      self._is_different = False
+      self._diff_record = None
+    else:
+      # Tell image_diff_db to add an entry for this diff asynchronously.
+      # Later on, we will call image_diff_db.get_diff_record() to find it.
+      self._is_different = True
+      self._diff_record = _DIFF_RECORD_STILL_LOADING
+
+    if self._diff_record != None or download_all_images:
+      image_diff_db.add_image_pair(
+          expected_image_locator=imageA_relative_url,
+          expected_image_url=self.posixpath_join(imageA_base_url,
+                                                 imageA_relative_url),
+          actual_image_locator=imageB_relative_url,
+          actual_image_url=self.posixpath_join(imageB_base_url,
+                                               imageB_relative_url))
+
+  def as_dict(self):
+    """Returns a dictionary describing this ImagePair.
+
+    Uses the KEY__IMAGEPAIRS__* constants as keys.
+    """
+    asdict = {
+        KEY__IMAGEPAIRS__IMAGE_A_URL: self.imageA_relative_url,
+        KEY__IMAGEPAIRS__IMAGE_B_URL: self.imageB_relative_url,
+    }
+    asdict[KEY__IMAGEPAIRS__IS_DIFFERENT] = self._is_different
+    if self.expectations_dict:
+      asdict[KEY__IMAGEPAIRS__EXPECTATIONS] = self.expectations_dict
+    if self.extra_columns_dict:
+      asdict[KEY__IMAGEPAIRS__EXTRACOLUMNS] = self.extra_columns_dict
+    if self.source_json_file:
+      asdict[KEY__IMAGEPAIRS__SOURCE_JSON_FILE] = self.source_json_file
+    if self._diff_record is _DIFF_RECORD_STILL_LOADING:
+      # We have waited as long as we can to ask ImageDiffDB for details of
+      # this image diff.  Now we must block until ImageDiffDB can provide
+      # those details.
+      #
+      # TODO(epoger): Is it wasteful for every imagepair to have its own
+      # reference to image_diff_db?  If so, we could pass an image_diff_db
+      # reference into this method call instead...
+      self._diff_record = self._image_diff_db.get_diff_record(
+          expected_image_locator=self.imageA_relative_url,
+          actual_image_locator=self.imageB_relative_url)
+    if self._diff_record != None:
+      asdict[KEY__IMAGEPAIRS__DIFFERENCES] = self._diff_record.as_dict()
+    return asdict
+
+  @staticmethod
+  def posixpath_join(*args):
+    """Wrapper around posixpath.join().
+
+    Returns posixpath.join(*args), or None if any arg is None.
+    """
+    for arg in args:
+      if arg == None:
+        return None
+    return posixpath.join(*args)