Uncatchable error in NodeJS Agones SDK when calling shutdown()

[jhowcrof]

What happened:
Error logged from NodeJS Agones SDK:
Error: 14 UNAVAILABLE: Connection dropped

from watchGameServer. This happened after calling shutdown intentionally.

What you expected to happen:
I should be able to catch this error, and I cannot because it is wrapped in a callback. The error callback is executed asynchronously, so It throws into a separate execution context and crashes the node process as an unhandled exception.

Instead, watchGameServer should take an onError callback or something, so that I can handle this sort of error.

How to reproduce it (as minimally and precisely as possible):

Just call watchGameServer, then call shutdown.

Anything else we need to know?:

Environment:

• Agones version: 1.17.0
• Kubernetes version (use kubectl version): v1.22.2
• Cloud provider or hardware configuration: GKE
• Install method (yaml/helm): helm
• Troubleshooting guide log(s):
• Others:

[roberthbailey]

@steven-supersolid - have you run across this in your use of the nodejs SDK?

[steven-supersolid]

It looks like it can occur here https://github.com/googleforgames/agones/blob/main/sdks/nodejs/src/agonesSDK.js#L130

There is a related test but it only verifies the catching of a specific error, not throwing asynchronously https://github.com/googleforgames/agones/blob/main/sdks/nodejs/spec/agonesSDK.spec.js#L274

I wonder why the same problem does not occur when using the example code but could be an edge case https://github.com/googleforgames/agones/blob/main/examples/nodejs-simple/src/index.js#L43

I think the idea of a 2nd optional callback to watchGameServer is perfect and we just call that with the error if it is present, or do nothing if it is not, removing the throw as it has no benefit. We can also remove the capture of the specific grpc.status.CANCELLED error and let the client code decide what to do with any errors.

I can make the PR within the next couple of days unless anyone else wants to? I would include:

• Code change above
• New test under watchGameServer describe
• Remove test for CANCELLED errors
• Update example code