Updating Blob.exists to accept a client.

Towards #952, removing connection from methods / constructors.

Author: dhermes

gcloud/storage/blob.py

@@ -200,18 +200,20 @@ def generate_signed_url(self, expiration, method='GET',
             api_access_endpoint=_API_ACCESS_ENDPOINT,
             expiration=expiration, method=method)
 
-    def exists(self, connection=None):
+    def exists(self, client=None):
         """Determines whether or not this blob exists.
 
-        :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: boolean
         :returns: True if the blob exists in Cloud Storage.
         """
-        connection = _require_connection(connection)
+        if client is None:
+            connection = _require_connection()
+        else:
+            connection = client.connection
         try:
             # We only need the status code (200 or not) so we seek to
             # minimize the returned payload.

gcloud/storage/test_blob.py

@@ -257,19 +257,32 @@ def test_exists_miss(self):
         NONESUCH = 'nonesuch'
         not_found_response = {'status': NOT_FOUND}
         connection = _Connection(not_found_response)
+        client = _Client(connection)
         bucket = _Bucket()
         blob = self._makeOne(NONESUCH, bucket=bucket)
-        self.assertFalse(blob.exists(connection=connection))
+        self.assertFalse(blob.exists(client=client))
+
+    def test_exists_implicit(self):
+        from gcloud.storage._testing import _monkey_defaults
+        from six.moves.http_client import NOT_FOUND
+        NONESUCH = 'nonesuch'
+        not_found_response = {'status': NOT_FOUND}
+        connection = _Connection(not_found_response)
+        bucket = _Bucket()
+        blob = self._makeOne(NONESUCH, bucket=bucket)
+        with _monkey_defaults(connection=connection):
+            self.assertFalse(blob.exists())
 
     def test_exists_hit(self):
         from six.moves.http_client import OK
         BLOB_NAME = 'blob-name'
         found_response = {'status': OK}
         connection = _Connection(found_response)
+        client = _Client(connection)
         bucket = _Bucket()
         blob = self._makeOne(BLOB_NAME, bucket=bucket)
         bucket._blobs[BLOB_NAME] = 1
-        self.assertTrue(blob.exists(connection=connection))
+        self.assertTrue(blob.exists(client=client))
 
     def test_rename_w_implicit_connection(self):
         from gcloud.storage._testing import _monkey_defaults
@@ -307,24 +320,26 @@ def test_delete_w_implicit_connection(self):
         BLOB_NAME = 'blob-name'
         not_found_response = {'status': NOT_FOUND}
         connection = _Connection(not_found_response)
+        client = _Client(connection)
         bucket = _Bucket()
         blob = self._makeOne(BLOB_NAME, bucket=bucket)
         bucket._blobs[BLOB_NAME] = 1
         with _monkey_defaults(connection=connection):
             blob.delete()
-        self.assertFalse(blob.exists(connection=connection))
+        self.assertFalse(blob.exists(client=client))
         self.assertEqual(bucket._deleted, [(BLOB_NAME, connection)])
 
     def test_delete_w_explicit_connection(self):
         from six.moves.http_client import NOT_FOUND
         BLOB_NAME = 'blob-name'
         not_found_response = {'status': NOT_FOUND}
         connection = _Connection(not_found_response)
+        client = _Client(connection)
         bucket = _Bucket()
         blob = self._makeOne(BLOB_NAME, bucket=bucket)
         bucket._blobs[BLOB_NAME] = 1
         blob.delete(connection=connection)
-        self.assertFalse(blob.exists(connection=connection))
+        self.assertFalse(blob.exists(client=client))
         self.assertEqual(bucket._deleted, [(BLOB_NAME, connection)])
 
     def _download_to_file_helper(self, chunk_size=None):