Don't check for file type in _find_base_file

Firstly, _find_base_file was differentiating between 2 different types
of 'non-original', but the caller was then treating them identically.
This differentiation was obviously redundant.

However, the caller was using them to populate originals. Note that
_scan_base_files has been called previously, and therefore originals
is already correctly populated. This means that _find_base_file does
not need to identify 'originals' at all.

Additionally, originals is only tracked at all so that 'originals' and
'non-originals' can be aged with different frequencies. This doesn't
really make any sense anyway, so this is a small step towards removing
a redundant config variable.

Change-Id: I893cfe23b48ee135ac6c14870d50d7f734c25247

nova/tests/unit/virt/libvirt/test_imagecache.py

@@ -258,7 +258,7 @@ class ImageCacheManagerTestCase(test.NoDBTestCase):
         res = list(image_cache_manager._find_base_file(base_dir, fingerprint))
 
         base_file = os.path.join(base_dir, fingerprint + '_sm')
-        self.assertEqual(res, [(base_file, True, False)])
+        self.assertEqual([base_file], res)
 
     def test_find_base_file_resized(self):
         fingerprint = '968dd6cc49e01aaa044ed11c0cce733e0fa44a6a'
@@ -278,7 +278,7 @@ class ImageCacheManagerTestCase(test.NoDBTestCase):
         res = list(image_cache_manager._find_base_file(base_dir, fingerprint))
 
         base_file = os.path.join(base_dir, fingerprint + '_10737418240')
-        self.assertEqual(res, [(base_file, False, True)])
+        self.assertEqual([base_file], res)
 
     def test_find_base_file_all(self):
         fingerprint = '968dd6cc49e01aaa044ed11c0cce733e0fa44a6a'
@@ -300,9 +300,7 @@ class ImageCacheManagerTestCase(test.NoDBTestCase):
         base_file1 = os.path.join(base_dir, fingerprint)
         base_file2 = os.path.join(base_dir, fingerprint + '_sm')
         base_file3 = os.path.join(base_dir, fingerprint + '_10737418240')
-        self.assertEqual(res, [(base_file1, False, False),
-                               (base_file2, True, False),
-                               (base_file3, False, True)])
+        self.assertEqual([base_file1, base_file2, base_file3], res)
 
     @contextlib.contextmanager
     def _make_base_file(self, lock=True, info=False):

nova/virt/libvirt/imagecache.py

@@ -209,8 +209,7 @@ class ImageCacheManager(imagecache.ImageCacheManager):
     def _find_base_file(self, base_dir, fingerprint):
         """Find the base file matching this fingerprint.
 
-        Yields the name of the base file, a boolean which is True if the image
-        is "small", and a boolean which indicates if this is a resized image.
+        Yields the name of a base file which exists.
         Note that it is possible for more than one yield to result from this
         check.
 
@@ -219,19 +218,19 @@ class ImageCacheManager(imagecache.ImageCacheManager):
         # The original file from glance
         base_file = os.path.join(base_dir, fingerprint)
         if os.path.exists(base_file):
-            yield base_file, False, False
+            yield base_file
 
         # An older naming style which can be removed sometime after Folsom
         base_file = os.path.join(base_dir, fingerprint + '_sm')
         if os.path.exists(base_file):
-            yield base_file, True, False
+            yield base_file
 
-        # Resized images
+        # Resized images (also legacy)
         resize_re = re.compile('.*/%s_[0-9]+$' % fingerprint)
         for img in self.unexplained_images:
             m = resize_re.match(img)
             if m:
-                yield img, False, True
+                yield img
 
     @staticmethod
     def _get_age_of_file(base_file):
@@ -358,13 +357,9 @@ class ImageCacheManager(imagecache.ImageCacheManager):
             LOG.debug('Image id %(id)s yields fingerprint %(fingerprint)s',
                       {'id': img,
                        'fingerprint': fingerprint})
-            for result in self._find_base_file(base_dir, fingerprint):
-                base_file, image_small, image_resized = result
+            for base_file in self._find_base_file(base_dir, fingerprint):
                 self._mark_in_use(img, base_file)
 
-                if not image_small and not image_resized:
-                    self.originals.append(base_file)
-
         # Elements remaining in unexplained_images might be in use
         inuse_backing_images = self._list_backing_images()
         for backing_path in inuse_backing_images: