new tool: download all GM images for a given builder, ready for skdiff

gm/rebaseline_server/download_actuals_test.py

Index: gm/rebaseline_server/download_actuals_test.py
diff --git a/gm/rebaseline_server/download_actuals_test.py b/gm/rebaseline_server/download_actuals_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..aeb1dce47f82d2263eadd3ea8e4bc585990aa40d
--- /dev/null
+++ b/gm/rebaseline_server/download_actuals_test.py
@@ -0,0 +1,168 @@
+#!/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.
+
+Test download.py
+
+TODO(epoger): Create a command to update the expected results (in
+OUTPUT_DIR_EXPECTED) when appropriate.  For now, you should:
+1. examine the results in OUTPUT_DIR_ACTUAL and make sure they are ok
+2. rm -rf OUTPUT_DIR_EXPECTED
+3. mv OUTPUT_DIR_ACTUAL OUTPUT_DIR_EXPECTED
+Although, if you're using an SVN checkout, this will blow away .svn directories
+within OUTPUT_DIR_EXPECTED, which wouldn't be good...
+
+"""
+
+# System-level imports
+import filecmp
+import os
+import shutil
+import tempfile
+import unittest
+import urllib
+
+# Imports from within Skia
+import download_actuals
+
+PARENT_DIR = os.path.dirname(os.path.realpath(__file__))
+INPUT_DIR = os.path.join(PARENT_DIR, 'tests', 'inputs')
+OUTPUT_DIR_ACTUAL   = os.path.join(PARENT_DIR, 'tests', 'outputs', 'actual')
+OUTPUT_DIR_EXPECTED = os.path.join(PARENT_DIR, 'tests', 'outputs', 'expected')
+
+
+class DownloadTest(unittest.TestCase):
+
+  def setUp(self):
+    self._temp_dir = tempfile.mkdtemp()
+    self._output_dir_actual   = os.path.join(OUTPUT_DIR_ACTUAL, self.id())
+    self._output_dir_expected = os.path.join(OUTPUT_DIR_EXPECTED, self.id())
+    create_empty_dir(self._output_dir_actual)
+
+  def tearDown(self):
+    shutil.rmtree(self._temp_dir)
+    if os.path.exists(self._output_dir_expected):
+      different_files = find_different_files(self._output_dir_actual,
+                                             self._output_dir_expected)
+      # Maybe we should move this assert elsewhere?  It's unusual to see an
+      # assert within tearDown(), but my thinking was:
+      # 1. Every test case will have some collection of output files that need
+      #    to be validated.
+      # 2. So put that validation within tearDown(), which will be called after
+      #    every test case!
+      #
+      # I have confirmed that the test really does fail if this assert is
+      # triggered.
+      #
+      # Ravi notes: if somebody later comes along and adds cleanup code below
+      # this assert, then if tests fail, the artifacts will not be cleaned up.
+      assert (not different_files), \
+        ('found differing files between actual dir %s and expected dir %s: %s' %
+         (self._output_dir_actual, self._output_dir_expected, different_files))
+
+  def shortDescription(self):
+    """Tell unittest framework to not print docstrings for test cases."""
+    return None
+
+  def test_fetch(self):
+    """Tests fetch() of GM results from actual-results.json ."""
+    downloader = download_actuals.Download(
+        actuals_base_url=download_actuals.create_filepath_url(
+            os.path.join(INPUT_DIR, 'gm-actuals')),
+        gm_actuals_root_url=download_actuals.create_filepath_url(
+            os.path.join(INPUT_DIR, 'fake-gm-imagefiles')))
+    downloader.fetch(
+        builder_name='Test-Android-GalaxyNexus-SGX540-Arm7-Release',
+        dest_dir=self._output_dir_actual)
+
+  def test_create_filepath_url(self):
+    """Tests create_filepath_url(). """
+    with self.assertRaises(Exception):
+      url_or_path.create_filepath_url('http://1.2.3.4/path')
+    # Pass absolute filepath.
+    self.assertEquals(
+        download_actuals.create_filepath_url(
+            '%sdir%sfile' % (os.path.sep, os.path.sep)),
+        'file:///dir/file')
+    # Pass relative filepath.
+    self.assertEquals(
+        download_actuals.create_filepath_url(os.path.join('dir', 'file')),
+        'file://%s/dir/file' % urllib.pathname2url(os.getcwd()))
+
+  def test_copy_contents(self):
+    """Tests copy_contents(). """
+    contents = 'these are the contents'
+    tempdir_path = tempfile.mkdtemp()
+    try:
+      source_path = os.path.join(tempdir_path, 'source')
+      source_url = download_actuals.create_filepath_url(source_path)
+      with open(source_path, 'w') as source_handle:
+        source_handle.write(contents)
+      dest_path = os.path.join(tempdir_path, 'new_subdir', 'dest')
+      # Destination subdir does not exist, so copy_contents() should fail
+      # if create_subdirs_if_needed is False.
+      with self.assertRaises(Exception):
+        download_actuals.copy_contents(source_url=source_url,
+                                       dest_path=dest_path,
+                                       create_subdirs_if_needed=False)
+      # If create_subdirs_if_needed is True, it should work.
+      download_actuals.copy_contents(source_url=source_url,
+                                     dest_path=dest_path,
+                                     create_subdirs_if_needed=True)
+      self.assertEquals(open(dest_path).read(), contents)
+    finally:
+      shutil.rmtree(tempdir_path)
+
+
+# TODO(epoger): create_empty_dir(), find_different_files(), etc. should be
+# extracted from this file to some common location, where they can be shared
+# with results_test.py and other users.
+
+def create_empty_dir(path):
+  """Create an empty directory at the given path."""
+  if os.path.isdir(path):
+    shutil.rmtree(path)
+  elif os.path.lexists(path):
+    os.remove(path)
+  os.makedirs(path)
+
+
+def find_different_files(dir1, dir2, ignore_subtree_names=None):
+  """Returns a list of any files that differ between the directory trees rooted
+  at dir1 and dir2.
+
+  Args:
+    dir1: root of a directory tree; if nonexistent, will raise OSError
+    dir2: root of another directory tree; if nonexistent, will raise OSError
+    ignore_subtree_names: list of subtree directory names to ignore;
+          defaults to ['.svn'], so all SVN files are ignores
+
+  TODO(epoger): include the dirname within each filename (not just the
+  basename), to make it easier to locate any differences
+  """
+  differing_files = []
+  if ignore_subtree_names is None:
+    ignore_subtree_names = ['.svn']
+  dircmp = filecmp.dircmp(dir1, dir2, ignore=ignore_subtree_names)
+  differing_files.extend(dircmp.left_only)
+  differing_files.extend(dircmp.right_only)
+  differing_files.extend(dircmp.common_funny)
+  differing_files.extend(dircmp.diff_files)
+  differing_files.extend(dircmp.funny_files)
+  for common_dir in dircmp.common_dirs:
+    differing_files.extend(find_different_files(
+        os.path.join(dir1, common_dir), os.path.join(dir2, common_dir)))
+  return differing_files
+
+
+def main():
+  suite = unittest.TestLoader().loadTestsFromTestCase(DownloadTest)
+  unittest.TextTestRunner(verbosity=2).run(suite)
+
+
+if __name__ == '__main__':
+  main()