google-app-engine - 无法从另一个项目中的 GCS 获取服务 URL

Question

我正在尝试使用 GAE 图像服务，但遇到了问题。

我有两个项目。项目A有GAE，项目B有GCS bucket。这是因为一旦创建了项目，就无法更改 GAE 区域。

当从GAE调用get_serving_url到GCS bucket的对象时，出现如下异常。

Traceback (most recent call last):
  ...
  File "/base/data/home/apps/b~[PROJECT_NAME]/20161215t131056.397760967541775314/main.py", line 125, in _get_serving_url
    return get_serving_url(blob_key)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/images/__init__.py", line 1868, in get_serving_url
    return rpc.get_result()
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 613, in get_result
    return self.__get_result_hook(self)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/images/__init__.py", line 1972, in get_serving_url_hook
    raise _ToImagesError(e, readable_blob_key)
TransformationError

将它们放在同一个项目中时，不会抛出此异常。GAE 的服务帐户和项目 A 具有对存储桶和对象的完全访问权限。

还有什么我需要尝试的吗？

---

self 解决

我在 the docs of Image API in GAE/Java 找到了原因.

Important: If you serve images from Google Cloud Storage, you cannot serve an image from two separate apps. Only the first app that calls getServingUrl on the image can get the URL to serve it because that app has obtained ownership of the image. Any other app that subsequently calls getServingUrl on the image will therefore be unsuccessful. If a second app needs to serve the image, the app needs to first copy the image and then invoke getServingUrl on the copy.

我同时使用了另一个项目中的桶对象。

因此，我已正确验证 get_serving_url。

Answer 1

您不必使用服务网址。您可以从 GCS 提供文件:

https://storage.googleapis.com/your_bucket/your_filename

或SDK http://localhost:8080/_ah/gcs/your_bucket/your_filename