storage: Export symbols of apiv2/storagepb

[AndreasBergmeier6176]

Is your feature request related to a problem? Please describe.

Previously it was not easily possible to write unit testing against cloud storage bindings. With the new GRPC API this is now possible. Currently though one must fork this repo and export the internal symbols manually.

Describe the solution you'd like

It would be better to have the generated symbols publicly accessible.

Describe alternatives you've considered

Since bindings get statically registered upon loading not sure whether there is really any alternative.

Additional context

Not sure how migration could happen since currently the reflection path is used in registering. Changing this path might lead to other problems?

[tritone]

@codyoss what do you think about this?

The storage/v2 API recently hit GA so I wouldn't be opposed at this point.

[kazegusuri]

Same situation at this issue. When I create another pb files from proto for apiv2.storagepb for testing instead of using generated files provided by google-cloud-go, the namespace conflict happens. So we cannot create a mock or fake server for storagev2.

[AndreasBergmeier6176]

For the time being you can use our fork here: https://github.com/AndreasBergmeier6176/google-cloud-go

Need replace cloud.google.com/go/storage => github.com/AndreasBergmeier6176/google-cloud-go/storage v1.47.2 then.

[codyoss]

@tritone Seems reasonable to me