1 files changed, 24 insertions, 4 deletions
diff --git a/glanceclient/common/utils.py b/glanceclient/common/utils.py
index dee9978..bc0c0eb 100644
--- a/glanceclient/common/utils.py
+++ b/glanceclient/common/utils.py
@@ -28,10 +28,10 @@ import uuid
 
 import six
 
-if os.name == 'nt':
-    import msvcrt
-else:
-    msvcrt = None
+if os.name == 'nt':  # noqa
+    import msvcrt  # noqa
+else:  # noqa
+    msvcrt = None  # noqa
 
 from oslo_utils import encodeutils
 from oslo_utils import strutils
@@ -449,6 +449,26 @@ def integrity_iter(iter, checksum):
                       (md5sum, checksum))
 
 
+def serious_integrity_iter(iter, hasher, hash_value):
+    """Check image data integrity using the Glance "multihash".
+
+    :param iter: iterable containing the image data
+    :param hasher: a hashlib object
+    :param hash_value: hexdigest of the image data
+    :raises: IOError if the hashdigest of the data is not hash_value
+    """
+    for chunk in iter:
+        yield chunk
+        if isinstance(chunk, six.string_types):
+            chunk = six.b(chunk)
+        hasher.update(chunk)
+    computed = hasher.hexdigest()
+    if computed != hash_value:
+        raise IOError(errno.EPIPE,
+                      'Corrupt image download. Hash was %s expected %s' %
+                      (computed, hash_value))
+
+
 def memoized_property(fn):
     attr_name = '_lazy_once_' + fn.__name__