Add more info to checksum exception

If an image cannot be downloaded for some reason, it is helpful for
operators to have the image path, checksum, and calculated checksums
available easily from the API.

Change-Id: I6a2fb46726245cebd730b5c51d4f25f8465f1658

ironic_python_agent/errors.py

@@ -150,10 +150,14 @@ class ImageChecksumError(RESTError):
     """Error raised when an image fails to verify against its checksum."""
 
     message = 'Error verifying image checksum'
+    details_str = ('Image failed to verify against checksum. location: {0}; '
+                   'image ID: {1}; image checksum: {2}; verification '
+                   'checksum: {3}')
 
-    def __init__(self, image_id):
-        details = 'Image with id {0} failed to verify against checksum.'
-        details = details.format(image_id)
+    def __init__(self, image_id, image_location, checksum,
+                 calculated_checksum):
+        details = self.details_str.format(image_location, image_id, checksum,
+                                          calculated_checksum)
         super(ImageChecksumError, self).__init__(details)
 
 

ironic_python_agent/extensions/standby.py

@@ -157,8 +157,7 @@ def _download_image(image_info):
     LOG.info("Image downloaded from {0} in {1} seconds".format(image_location,
                                                                totaltime))
 
-    if not _verify_image(image_info, image_location):
-        raise errors.ImageChecksumError(image_info['id'])
+    _verify_image(image_info, image_location)
 
 
 def _verify_image(image_info, image_location):
@@ -175,10 +174,12 @@ def _verify_image(image_info, image_location):
     hash_digest = hash_.hexdigest()
     if hash_digest == checksum:
         return True
-    log_msg = ('Image verification failed. Location: {0};'
-               'image hash: {1}; verification hash: {2}')
-    LOG.warning(log_msg.format(image_location, checksum, hash_digest))
-    return False
+
+    LOG.error(errors.ImageChecksumError.details_str.format(
+        image_location, image_info['id'], checksum, hash_digest))
+
+    raise errors.ImageChecksumError(image_location, image_info['id'], checksum,
+                                    hash_digest)
 
 
 def _validate_image_info(ext, image_info=None, **kwargs):

ironic_python_agent/tests/unit/extensions/test_standby.py

@@ -236,7 +236,8 @@ class TestStandbyExtension(test_base.BaseTestCase):
         image_info = self._build_fake_image_info()
         response = requests_mock.return_value
         response.status_code = 200
-        verify_mock.return_value = False
+        verify_mock.side_effect = errors.ImageChecksumError(
+            'foo', '/bar/foo', 'incorrect', 'correct')
         self.assertRaises(errors.ImageChecksumError,
                           standby._download_image,
                           image_info)
@@ -266,8 +267,9 @@ class TestStandbyExtension(test_base.BaseTestCase):
         open_mock.return_value.__enter__.return_value = file_mock
         image_location = '/foo/bar'
 
-        verified = standby._verify_image(image_info, image_location)
-        self.assertFalse(verified)
+        self.assertRaises(errors.ImageChecksumError,
+                          standby._verify_image,
+                          image_info, image_location)
         self.assertEqual(md5_mock.call_count, 1)
 
     @mock.patch('ironic_python_agent.hardware.dispatch_to_managers',

ironic_python_agent/tests/unit/test_errors.py

@@ -106,7 +106,9 @@ class TestErrors(test_base.BaseTestCase):
                  (errors.LookupAgentInterfaceError(DETAILS), SAME_DETAILS),
                  (errors.ImageDownloadError('image_id', DETAILS),
                      DIFF_CL_DETAILS),
-                 (errors.ImageChecksumError('image_id'), DIFF_CL_DETAILS),
+                 (errors.ImageChecksumError(
+                     'image_id', '/foo/image_id', 'incorrect', 'correct'),
+                  DIFF_CL_DETAILS),
                  (errors.ImageWriteError('device', 'exit_code', 'stdout',
                                          'stderr'),
                   DIFF_CL_DETAILS),