fix(otlp-grpc-exporter-base): avoid TypeError on exporter shutdown

[pichlermarc]

Which problem is this PR solving?

Calling shutdown() on any gRPC exporter throws a TypeError - preventing apps from gracefully shutting down.

The transport should call close() instead of shutdown() on the _client. The test I wrote for this case was entirely ineffective as I also managed to mock the wrong thing.

Fixes #4611

Short description of the changes

• call this._client?.close() instead of this._client?.shutdown()
• adapt tests to actually test that behavior

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Updated unit tests

[dyladan]

Looks good but I'm curious how the types allowed shutdown to be called if it doesn't exist in the first place. Probably not important for this PR, but our GRPC types might be wrong

[pichlermarc]

Looks good but I'm curious how the types allowed shutdown to be called if it doesn't exist in the first place. Probably not important for this PR, but our GRPC types might be wrong

Yes, I've been using any instead of Client from the gRPC library as there are no types for the service client functions itself.
I've pushed a commit to use the Client type.

We still have to use it as any when we call export(), but at least the common Client functions are now typed.

[jdespatis]

hello @pichlermarc,

Thanks for your fix (I need it to force flushing BatchSpanProcessor when my script ends, on beforeExit event)

Can you please publish this new version ?
so that @Vunovati can update his PR Vunovati/otlp-logger#61 to release new versions.

[pichlermarc]

hello @pichlermarc,

Thanks for your fix (I need it to force flushing BatchSpanProcessor when my script ends, on beforeExit event)

Can you please publish this new version ? so that @Vunovati can update his PR Vunovati/otlp-logger#61 to release new versions.

On it, hoping to get the release out by monday 🙂