Support for Spanner Emulator

[eddumelendez]

cloud sdk version 287.0.0 has release a beta spanner emulator. I am wondering if the project can start with the support for it.

[elefeint]

Related: we have a Pub/Sub emulator rule that only lives in Spring Cloud Streams tests. I wonder if we should create a spring-cloud-gcp-test-support project to put those emulator rules in.

[eddumelendez]

I wonder if we should create a spring-cloud-gcp-test-support project to put those emulator rules in.

I like the idea.

Also, this tasks will help to find a place for #2281

[eddumelendez]

@elefeint thinking about having spring-cloud-gcp-test-support and moving the emulators auto-configuration doesn't seems right due to can be also apply for local development. spring-boot provides database, ldap and mongo for local development but in the test-support we can provide another kind of stuff like annotations which help and improve the emulators autoconfiguration for test specifically.

[elefeint]

Right, there are two separate things. One is making emulator work for general case (@dmitry-s is looking into that; it might Just Work because we don't instantiate a transport channel ourselves, relying instead on the client library's default behavior).
The other one is easing use of emulator in integration tests; that's what the test support could help with.

[dmitry-s]

Closed in favor of #2318