Updating Blob.download* methods to accept a client.

Towards googleapis#952, removing connection from methods / constructors.

Also adding a temporary Blob._client_or_connection method
to allow switching from an explicit client to an implicit
connection.

gcloud/storage/blob.py

@@ -200,6 +200,24 @@ def generate_signed_url(self, expiration, method='GET',
  api_access_endpoint=_API_ACCESS_ENDPOINT,
  expiration=expiration, method=method)
 
+ @staticmethod
+ def _client_or_connection(client):
+ """Temporary method to get a connection from a client.
+
+ If the client is null, gets the connection from the environment.
+
+ :type client: :class:`gcloud.storage.client.Client` or ``NoneType``
+ :param client: Optional. The client to use. If not passed, falls back
+ to default connection.
+
+ :rtype: :class:`gcloud.storage.connection.Connection`
+ :returns: The connection determined from the ``client`` or environment.
+ """
+ if client is None:
+ return _require_connection()
+ else:
+ return client.connection
+
  def exists(self, client=None):
  """Determines whether or not this blob exists.
 
@@ -210,10 +228,7 @@ def exists(self, client=None):
  :rtype: boolean
  :returns: True if the blob exists in Cloud Storage.
  """
- if client is None:
- connection = _require_connection()
- else:
- connection = client.connection
+ connection = self._client_or_connection(client)
  try:
  # We only need the status code (200 or not) so we seek to
  # minimize the returned payload.
@@ -275,20 +290,19 @@ def delete(self, connection=None):
  connection = _require_connection(connection)
  return self.bucket.delete_blob(self.name, connection=connection)
 
- def download_to_file(self, file_obj, connection=None):
+ def download_to_file(self, file_obj, client=None):
  """Download the contents of this blob into a file-like object.
 
  :type file_obj: file
  :param file_obj: A file handle to which to write the blob's data.
 
- :type connection: :class:`gcloud.storage.connection.Connection` or
- ``NoneType``
- :param connection: Optional. The connection to use when sending
- requests. If not provided, falls back to default.
+ :type client: :class:`gcloud.storage.client.Client` or ``NoneType``
+ :param client: Optional. The client to use. If not passed, falls back
+ to default connection.
 
  :raises: :class:`gcloud.exceptions.NotFound`
  """
- connection = _require_connection(connection)
+ connection = self._client_or_connection(client)
  download_url = self.media_link
 
  # Use apitools 'Download' facility.
@@ -307,39 +321,37 @@ def download_to_file(self, file_obj, connection=None):
  download.StreamInChunks(callback=lambda *args: None,
  finish_callback=lambda *args: None)
 
- def download_to_filename(self, filename, connection=None):
+ def download_to_filename(self, filename, client=None):
  """Download the contents of this blob into a named file.
 
  :type filename: string
  :param filename: A filename to be passed to ``open``.
 
- :type connection: :class:`gcloud.storage.connection.Connection` or
- ``NoneType``
- :param connection: Optional. The connection to use when sending
- requests. If not provided, falls back to default.
+ :type client: :class:`gcloud.storage.client.Client` or ``NoneType``
+ :param client: Optional. The client to use. If not passed, falls back
+ to default connection.
 
  :raises: :class:`gcloud.exceptions.NotFound`
  """
  with open(filename, 'wb') as file_obj:
- self.download_to_file(file_obj, connection=connection)
+ self.download_to_file(file_obj, client=client)
 
  mtime = time.mktime(self.updated.timetuple())
  os.utime(file_obj.name, (mtime, mtime))
 
- def download_as_string(self, connection=None):
+ def download_as_string(self, client=None):
  """Download the contents of this blob as a string.
 
- :type connection: :class:`gcloud.storage.connection.Connection` or
- ``NoneType``
- :param connection: Optional. The connection to use when sending
- requests. If not provided, falls back to default.
+ :type client: :class:`gcloud.storage.client.Client` or ``NoneType``
+ :param client: Optional. The client to use. If not passed, falls back
+ to default connection.
 
  :rtype: bytes
  :returns: The data stored in this blob.
  :raises: :class:`gcloud.exceptions.NotFound`
  """
  string_buffer = BytesIO()
- self.download_to_file(string_buffer, connection=connection)
+ self.download_to_file(string_buffer, client=client)
  return string_buffer.getvalue()
 
  def upload_from_file(self, file_obj, rewind=False, size=None,

gcloud/storage/test_blob.py

@@ -355,6 +355,7 @@ def _download_to_file_helper(self, chunk_size=None):
  (chunk1_response, b'abc'),
  (chunk2_response, b'def'),
  )
+ client = _Client(connection)
  bucket = _Bucket()
  MEDIA_LINK = 'http://example.com/media/'
  properties = {'mediaLink': MEDIA_LINK}
@@ -363,7 +364,7 @@ def _download_to_file_helper(self, chunk_size=None):
  blob._CHUNK_SIZE_MULTIPLE = 1
  blob.chunk_size = chunk_size
  fh = BytesIO()
- blob.download_to_file(fh, connection=connection)
+ blob.download_to_file(fh, client=client)
  self.assertEqual(fh.getvalue(), b'abcdef')
 
  def test_download_to_file_default(self):
@@ -387,6 +388,7 @@ def test_download_to_filename(self):
  (chunk1_response, b'abc'),
  (chunk2_response, b'def'),
  )
+ client = _Client(connection)
  bucket = _Bucket()
  MEDIA_LINK = 'http://example.com/media/'
  properties = {'mediaLink': MEDIA_LINK,
@@ -395,7 +397,7 @@ def test_download_to_filename(self):
  blob._CHUNK_SIZE_MULTIPLE = 1
  blob.chunk_size = 3
  with NamedTemporaryFile() as f:
- blob.download_to_filename(f.name, connection=connection)
+ blob.download_to_filename(f.name, client=client)
  f.flush()
  with open(f.name, 'rb') as g:
  wrote = g.read()
@@ -416,13 +418,14 @@ def test_download_as_string(self):
  (chunk1_response, b'abc'),
  (chunk2_response, b'def'),
  )
+ client = _Client(connection)
  bucket = _Bucket()
  MEDIA_LINK = 'http://example.com/media/'
  properties = {'mediaLink': MEDIA_LINK}
  blob = self._makeOne(BLOB_NAME, bucket=bucket, properties=properties)
  blob._CHUNK_SIZE_MULTIPLE = 1
  blob.chunk_size = 3
- fetched = blob.download_as_string(connection=connection)
+ fetched = blob.download_as_string(client=client)
  self.assertEqual(fetched, b'abcdef')
 
  def test_upload_from_file_size_failure(self):