gapic-generator-cloud docker invocation fails if --ruby-cloud-gem-name option is not supplied

[viacheslav-rostovtsev]

when invoking gapic-generator-cloud docker like this:

$ docker run --rm --user $UID \
  --mount type=bind,source=`pwd`/google/showcase/v1beta1,destination=/in/google/showcase/v1beta1,readonly \
  --mount type=bind,source=`pwd`/showcase-ruby,destination=/out \
  gcr.io/gapic-images/gapic-generator-ruby:latest

the generator will fail with the Nil reference exception.

/usr/local/bundle/gems/gapic-generator-0.0.1/templates/default/helpers/presenters/gem_presenter.rb:62 \  
 :in `namespace': undefined method `split' for nil:NilClass (ActionView::Template::Error)

This can be remedied by supplying the docker generator with the --ruby-cloud-gem-name parameter:

$ docker run --rm --user $UID \
  --mount type=bind,source=`pwd`/google/showcase/v1beta1,destination=/in/google/showcase/v1beta1,readonly \
  --mount type=bind,source=`pwd`/showcase-ruby,destination=/out \
  gcr.io/gapic-images/gapic-generator-ruby:latest --ruby-cloud-gem-name=showcase

(this generates correctly)

There should be a sensible default for the gemname we can add to the gapic-generator-ruby to avoid this issue.

[quartzmo]

There should be a sensible default for the gemname we can add to the gapic-generator-ruby to avoid this issue.

I agree, it seems that we should be able to just derive the gem name from the first three namespaces (Google::Cloud::VideoIntelligence), right?