Feedback updates

gcloud/_helpers.py

@@ -394,6 +394,30 @@ def _to_bytes(value, encoding='ascii'):
         raise TypeError('%r could not be converted to bytes' % (value,))
 
 
+def _from_bytes(value):
+    """Converts bytes to a string value, if necessary.
+
+    Args:
+        value: The string/bytes value to be converted.
+
+    Returns:
+        The original value converted to unicode (if bytes) or as passed in
+        if it started out as unicode.
+
+    Raises:
+        ValueError if the value could not be converted to unicode.
+
+    :type value: bytes
+    :param value: bytes value to attempt string conversion on.
+    """
+    result = (value.decode('utf-8')
+              if isinstance(value, six.binary_type) else value)
+    if isinstance(result, six.text_type):
+        return result
+    else:
+        raise ValueError('%r could not be converted to unicode' % (value,))
+
+
 def _pb_timestamp_to_datetime(timestamp):
     """Convert a Timestamp protobuf to a datetime object.
 

gcloud/storage/blob.py

@@ -14,7 +14,7 @@
 
 """Create / interact with Google Cloud Storage blobs."""
 
-import base64
+from base64 import b64encode
 import copy
 import hashlib
 from io import BytesIO
@@ -28,6 +28,8 @@
 from six.moves.urllib.parse import quote
 
 from gcloud._helpers import _rfc3339_to_datetime
+from gcloud._helpers import _to_bytes
+from gcloud._helpers import _from_bytes
 from gcloud.credentials import generate_signed_url
 from gcloud.exceptions import NotFound
 from gcloud.exceptions import make_exception
@@ -111,23 +113,6 @@ def path_helper(bucket_path, blob_name):
         """
         return bucket_path + '/o/' + quote(blob_name, safe='')
 
-    @staticmethod
-    def _get_customer_encryption_headers(key):
-        """Builds customer encyrption key headers
-
-        :type key: str
-        :param key: 32 byte key to build request key and hash.
-        """
-        headers = {}
-        key_hash = base64.encodestring(hashlib.sha256(key.encode('utf-8'))
-                                       .digest()).rstrip()
-        encoded_key = base64.encodestring(bytes(key.encode('utf-8'))).rstrip()
-        headers['X-Goog-Encryption-Algorithm'] = 'AES256'
-        headers['X-Goog-Encryption-Key'] = encoded_key.decode('utf-8')
-        headers['X-Goog-Encryption-Key-Sha256'] = key_hash.decode('utf-8')
-
-        return headers
-
     @property
     def acl(self):
         """Create our ACL on demand."""
@@ -343,7 +328,7 @@ def download_to_file(self, file_obj, key=None, client=None):
 
         headers = {}
         if key:
-            headers.update(self._get_customer_encryption_headers(key))
+            set_customer_encryption_headers(key, headers)
 
         request = Request(download_url, 'GET', headers)
 
@@ -417,7 +402,7 @@ def _check_response_error(request, http_response):
             raise make_exception(faux_response, http_response.content,
                                  error_info=request.url)
 
-    # pylint: disable=too-many-arguments,too-many-locals
+    # pylint: disable=too-many-locals
     def upload_from_file(self, file_obj, rewind=False, size=None, key=None,
                          content_type=None, num_retries=6, client=None):
         """Upload the contents of this blob from a file-like object.
@@ -498,7 +483,7 @@ def upload_from_file(self, file_obj, rewind=False, size=None, key=None,
         }
 
         if key:
-            headers.update(self._get_customer_encryption_headers(key))
+            set_customer_encryption_headers(key, headers)
 
         upload = Upload(file_obj, content_type, total_bytes,
                         auto_transfer=False)
@@ -923,3 +908,21 @@ def __init__(self, bucket_name, object_name):
         self.query_params = {'name': object_name}
         self._bucket_name = bucket_name
         self._relative_path = ''
+
+
+def set_customer_encryption_headers(key, headers):
+    """Builds customer encyrption key headers
+
+    :type key: str
+    :param key: 32 byte key to build request key and hash.
+
+    :type headers: dict
+    :param headers: dict of HTTP headers being sent in request.
+    """
+    key = _to_bytes(key)
+    sha256_key = hashlib.sha256(key).digest()
+    key_hash = b64encode(sha256_key).rstrip()
+    encoded_key = b64encode(key).rstrip()
+    headers['X-Goog-Encryption-Algorithm'] = 'AES256'
+    headers['X-Goog-Encryption-Key'] = _from_bytes(encoded_key)
+    headers['X-Goog-Encryption-Key-Sha256'] = _from_bytes(key_hash)