v0.16.3 comes with incompatible grpc versions

[ctavan]

When using yarn, v0.16.3 introduced the following error for me:

TypeError: Channel's second argument must be a ChannelCredentials
    at ServiceClient.Client (/app/node_modules/grpc/src/client.js:472:19)
    at new ServiceClient (/app/node_modules/grpc/src/client.js:884:12)
    at /app/node_modules/google-gax/lib/grpc.js:251:12

The reason is that @google-cloud/pubsub now defines grpc@^1.8.4 as a direct dependency as well as google-gax@^0.14.2.

google-gax@^0.14.2 however currently pins its grpc dependency to grpc@~1.7.2, see googleapis/gax-nodejs#178

This altogether breaks v0.16.3 of @google-cloud/pubsub and provokes the above error. Pinning grpc@~1.7.2 back in @google-cloud/pubsub works as a workaround for now.

Related:

• Publishing a new version gax-nodejs#173
• Release gRPC 1.8.x #49

[cmdshepard]

I can confirm this as well.
This is related to issue #31