Setting experimental `metricsAggregator: true` does not respect `enabled` setting and hangs on connecting

[Jimmy89]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which SDK are you using?

@sentry/serverless

SDK Version

7.103.0

Framework Version

NodeJS 20.10

Link to Sentry event

No response

SDK Setup

Index.mjs

import Sentry from "@sentry/serverless";
// Important: no DSN is inserted, no Sentry environment variables are set, these are all values given to Sentry
Sentry.AWSLambda.init({
    enabled: false,
    _experiments: {
        metricsAggregator: true,
    },
});

console.log("I keep running");

Steps to Reproduce

1. Run code with node index.mjs
2. The node process will never stop, it 'hangs' on the metricsAggregator to 'finish' or something, which never happens.

Expected Result

Sentry not doing anything as it is disabled.

Actual Result

Need to kill the node process the hard way.

[AbhiPrasad]

If you add debug: true, to your Sentry.init, what shows up in the logs?

[Jimmy89]

Only the basic Sentry Logger [warn]: No DSN provided, client will not send events. message (which is expected as I also disable Sentry), whether the plugin is added or not.
No other messages. Were you able to reproduce the issue as well?

[AbhiPrasad]

I was able to reproduce this issue. It seems something is being problematic and not letting the node process exit.

For now you can resolve this by only setting the metricsAggregator experiment if the dsn is defined. We currently don't have the bandwidth to dig deeper for now, but PRs are welcome if you would like to help us out! Thanks.