From 9c8f910baf95dbcb6c93e3150653e2ca111b3544 Mon Sep 17 00:00:00 2001
From: Martey Dodoo <martey@mobolic.com>
Date: Fri, 11 Jan 2019 10:23:30 -0500
Subject: [PATCH] Allow custom endpoints with Google Cloud Storage.

Add new `GS_CUSTOM_ENDPOINT` setting to allow usage of custom
domains/URLs with Google Cloud Storage, similar to
`AWS_S3_CUSTOM_DOMAIN`.

This upgrades the minimum version of google-cloud-storage to 1.15.0.
---
 AUTHORS                     |  1 +
 docs/backends/gcloud.rst    |  5 +++++
 setup.py                    |  2 +-
 storages/backends/gcloud.py | 20 ++++++++++++++++++--
 tests/test_gcloud.py        | 12 ++++++++++++
 5 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/AUTHORS b/AUTHORS
index 5f09414b4..fd4ab68ff 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -37,6 +37,7 @@ By order of apparition, thanks:
     * Jumpei Yoshimura (S3 docs)
     * Jon Dufresne
     * Rodrigo Gadea (Dropbox fixes)
+    * Martey Dodoo
 
 
 
diff --git a/docs/backends/gcloud.rst b/docs/backends/gcloud.rst
index e8d8b3dae..4f26ca429 100644
--- a/docs/backends/gcloud.rst
+++ b/docs/backends/gcloud.rst
@@ -142,6 +142,11 @@ rolled over into a temporary file on disk. Default is 0: Do not roll over.
 
 Sets Cache-Control HTTP header for the file, more about HTTP caching can be found `here <https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching#cache-control>`_
 
+``GS_CUSTOM_ENDPOINT`` (optional: default is ``None``)
+
+Sets a `custom endpoint <https://cloud.google.com/storage/docs/request-endpoints>`_,
+that will be used instead of ``https://storage.googleapis.com`` when generating URLs for files.
+
 ``GS_LOCATION`` (optional: default is ``''``)
 
 Subdirectory in which the files will be stored.
diff --git a/setup.py b/setup.py
index f7dd31c67..30a6a5172 100644
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@ def read(filename):
         'boto': ['boto>=2.32.0'],
         'boto3': ['boto3>=1.4.4'],
         'dropbox': ['dropbox>=7.2.1'],
-        'google': ['google-cloud-storage>=0.22.0'],
+        'google': ['google-cloud-storage>=1.15.0'],
         'libcloud': ['apache-libcloud'],
         'sftp': ['paramiko'],
     },
diff --git a/storages/backends/gcloud.py b/storages/backends/gcloud.py
index 86c5b2571..d4228c97e 100644
--- a/storages/backends/gcloud.py
+++ b/storages/backends/gcloud.py
@@ -8,6 +8,7 @@
 from django.utils import timezone
 from django.utils.deconstruct import deconstructible
 from django.utils.encoding import force_bytes, smart_str
+from django.utils.six.moves.urllib.parse import quote
 
 from storages.utils import (
     check_location, clean_name, get_available_overwrite_name, safe_join,
@@ -15,6 +16,7 @@
 )
 
 try:
+    from google.cloud.storage._signing import generate_signed_url_v2
     from google.cloud.storage.client import Client
     from google.cloud.storage.blob import Blob
     from google.cloud.exceptions import NotFound
@@ -86,6 +88,7 @@ class GoogleCloudStorage(Storage):
     project_id = setting('GS_PROJECT_ID')
     credentials = setting('GS_CREDENTIALS')
     bucket_name = setting('GS_BUCKET_NAME')
+    custom_endpoint = setting('GS_CUSTOM_ENDPOINT', None)
     location = setting('GS_LOCATION', '')
     auto_create_bucket = setting('GS_AUTO_CREATE_BUCKET', False)
     auto_create_acl = setting('GS_AUTO_CREATE_ACL', 'projectPrivate')
@@ -266,9 +269,22 @@ def url(self, name):
         name = self._normalize_name(clean_name(name))
         blob = self.bucket.blob(self._encode_name(name))
 
-        if self.default_acl == 'publicRead':
+        if not self.custom_endpoint and self.default_acl == 'publicRead':
             return blob.public_url
-        return blob.generate_signed_url(self.expiration)
+        elif self.default_acl == 'publicRead':
+            return '{storage_base_url}/{quoted_name}'.format(
+                storage_base_url=self.custom_endpoint,
+                quoted_name=quote(name.encode('utf-8')),
+            )
+        elif not self.custom_endpoint:
+            return blob.generate_signed_url(self.expiration)
+        else:
+            return generate_signed_url_v2(
+                self.credentials,
+                resource=quote(name.encode('utf-8')),
+                api_access_endpoint=self.custom_endpoint,
+                expiration=self.expiration,
+            )
 
     def get_available_name(self, name, max_length=None):
         name = clean_name(name)
diff --git a/tests/test_gcloud.py b/tests/test_gcloud.py
index 773250aa7..2ecf99f5a 100644
--- a/tests/test_gcloud.py
+++ b/tests/test_gcloud.py
@@ -358,6 +358,18 @@ def test_url_not_public_file_with_custom_expires(self):
         self.assertEqual(url, 'http://signed_url')
         blob.generate_signed_url.assert_called_with(timedelta(seconds=3600))
 
+    def test_custom_endpoint(self):
+        self.storage.custom_endpoint = "https://example.com"
+
+        self.storage.default_acl = 'publicRead'
+        url = "{}/{}".format(self.storage.custom_endpoint, self.filename)
+        self.assertEqual(self.storage.url(self.filename), url)
+
+        signed_url = 'https://signed_url'
+        self.storage.default_acl = 'projectPrivate'
+        gcloud.generate_signed_url_v2 = mock.MagicMock(return_value=signed_url)
+        self.assertEqual(self.storage.url(self.filename), signed_url)
+
     def test_get_available_name(self):
         self.storage.file_overwrite = True
         self.assertEqual(self.storage.get_available_name(