Hubs/Scopes Merge 15 - Replace ThreadLocal with scope storage

[adinauer]

#skip-changelog

📜 Description

Replace ThreadLocal in Sentry with scopes storage.

💡 Motivation and Context

Can use token to clean up forked Scopes. Can configure store to use OpenTelemetry Context under the hood (in a follow up PR).

💚 How did you test it?

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

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📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against 07545e7

[lbloder]

If not in globalHubMode, is it enough to clean the ThreadLocal in the calling thread?
What about scopes stored in other long-living threads, like worker threads or threads in ThreadPools that are reused, wouldn't the scopes in there live on? Would have been the same for Hub before the Hubs/Scopes merge.

If one would re-init Sentry, the ThreadLocal on the calling thread is cleaned, if, however there were long-living threads that had a reference to the initial Scopes instance, they would still use the initial version of Scopes when calling Sentry.captureX for example.

Not sure about the implications, just wanted to point out a potential issue.

Please correct me if I'm wrong :)

[adinauer]

Yeah, maybe we can give https://github.com/getsentry/sentry-java/pull/2711/files a try once we're done with most changes for the major.