问题描述
我最近使用 Google Cloud Platform (gcloud) 部署了一个较旧的 (Python 2.7) Google App Engine 应用程序,因为 appcfg 已停用。我在使用 images.get_serving_url 时遇到问题,不适用于上传的图像 blob。图像 API 正在返回“TransformationError”。在切换到谷歌云平台之前,此代码已在生产环境中运行多年。
需要注意的一点是,Google Cloud Platform 为 blob 创建了一个默认存储桶。以前,我认为 GAE 使用的是 Blobstore,因此即使此更改对开发人员来说是透明的,但在幕后可能发生了很多事情。我认为出于某种原因,我的应用在为存储在云存储桶中的文件创建图像 URL 时遇到问题。
我做了一个非常简单的测试用例来重现这个问题。是否有新的要求,或者这应该可行吗?
class testUpload(webapp.RequestHandler):
def get(self):
uploadUrl = blobstore.create_upload_url('/testUploadHandler')
print("Generated upload url: %s" % uploadUrl)
self.response.out.write("""
<html><body>
<form action="{0}" method="POST" enctype="multipart/form-data">
Upload File: <input type="file" name="file"><br>
<input type="submit" name="submit" value="Submit">
</form>
</body></html>""".format(uploadUrl))
class testUploadHandler(blobstore_handlers.BlobstoreUploadHandler):
def post(self):
logging.info("testUploadHandler called.")
upload = self.get_uploads()[0]
blob_key = upload.key()
image_url = images.get_serving_url(blob_key)
self.redirect(image_url)
部署的代码在web服务器上返回如下错误(本地开发服务器没问题):
Traceback (most recent call last):
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py",line 1535,in __call__
rv = self.handle_exception(request,response,e)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py",line 1529,in __call__
rv = self.router.dispatch(request,response)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py",line 1278,in default_dispatcher
return route.handler_adapter(request,line 1102,in __call__
return handler.dispatch()
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py",line 572,in dispatch
return self.handle_exception(e,self.app.debug)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py",line 570,in dispatch
return method(*args,**kwargs)
File "/base/data/home/apps/s~puzzleflow-dev/20210325t013659.433969250928848570/puzzleflow.py",line 4171,in post
image_url = images.get_serving_url(blob_key)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/1/google/appengine/api/images/__init__.py",line 1866,in get_serving_url
return rpc.get_result()
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py",line 615,in get_result
return self.__get_result_hook(self)
File "/base/alloc/tmpfs/dynamic_runtimes/python27g/fdc6d631da52d25b/python27/python27_lib/versions/1/google/appengine/api/images/__init__.py",line 1970,in get_serving_url_hook
raise _ToImagesError(e,readable_blob_key)
TransformationError
此外,您可以通过访问此链接(它应该是公开的)自己尝试:
https://puzzleflow-dev.appspot.com/testUpload
解决方法
问题是我已将访问控制切换为 Uniform,因为 Google 表示这是“推荐”设置。我对 Fine-Grained 和 Uniform 之间的区别不够了解,但将其切换回 Fine-Grained 解决了这个问题。