Add grpcio-gcp dependency for cloud spanner

[WeiranFang]

Add grpcio-gcp as extra dependency in google-api-core
Add grpcio-gcp as hard dependency in google-cloud-spanner

[tseaver]

Making grpcio-gcp a hard dependency of google-cloud-spanner seems like it involves some risk: I don't know how well that package is supported across all the platforms, but for instance the latest version has a Python2-only wheel as its only binary distribution. I can't find its repository, either.

/cc @snehashah16

[theacodes]

I'm going to send a PR to fix the wheel situation, then we can merge this.

The repo is at https://github.com/GoogleCloudPlatform/grpc-gcp-python

[theacodes]

Universal wheel PR: GoogleCloudPlatform/grpc-gcp-python#99

[WeiranFang]

Updated the min version for api_core and published universal wheel package for grpcio-gcp.

As for the release version for api-core and cloud-spanner, should I bump their versions now in this PR, or leave them for you guys when they are ready to release?

[theacodes]

No, releasetool will handle that.

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On Mon, Sep 10, 2018 at 12:56 PM Weiran Fang ***@***.***> wrote: Should I bump api core and cloud spanner versions in this PR, or leave them for you guys when they are ready to release? — You are receiving this because your review was requested. Reply to this email directly, view it on GitHub <#5904 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAPUc8TPEz-8E-LkEltLeWhBoikjElhRks5uZsQCgaJpZM4WfoOh> .

[WeiranFang]

No, releasetool will handle that.

Thanks! So the next step would be just to release api-core and cloud-spanner, right?

[theacodes]

Yes, once we merge this. I'll try to do this tomorrow morning. :)

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On Mon, Sep 10, 2018 at 2:22 PM Weiran Fang ***@***.***> wrote: No, releasetool will handle that. Thanks! So the next step would be just to release api-core and cloud-spanner, right? — You are receiving this because your review was requested. Reply to this email directly, view it on GitHub <#5904 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAPUc_X-hnE5HZjhjz8OXm_EB2UA7074ks5uZtgEgaJpZM4WfoOh> .

[tseaver]

We can't get tests passing for this PR until api_core/setup.py has the new version number.

[WeiranFang]

I think we should separate this into 2 pr, one for api core and another one for spanner. So we can release api core before spanner, correct?

[tseaver]

@WeiranFang This PR already touches api_core/setup.py: it just needs to bump the version number there so that the constraint in spanner/setup.py is satisfied. @theacodes will make the releases for the two in the order you suggest, but we can't merge without getting the tests passing first.

[WeiranFang]

I see, thanks for the clarification!