feat(logging): implement thread-safe logging with per-thread scope storage

[hjgraca]

Please provide the issue number

Issue number: #1076 #1077

Summary

Changes

This pull request introduces significant improvements to concurrency handling in the Powertools Logger, ensuring thread- and invocation-safe logging in AWS Lambda environments with concurrent execution (LMI). It achieves this by refactoring scope storage to be thread-local, adding comprehensive concurrency tests, and updating dependencies for better compatibility. The most important changes are grouped below.

Concurrency and Thread Safety Improvements:

• Refactored the Logger's scope storage to use a thread-safe ConcurrentDictionary keyed by Environment.CurrentManagedThreadId, isolating log scopes per thread and preventing cross-invocation contamination in concurrent Lambda executions (Logger.Scope.cs). [1] [2]
• Updated the RemoveAllKeys method to clear only the current thread's scope, further ensuring isolation between concurrent invocations (Logger.Scope.cs).

Dependency and Solution Updates:

• Upgraded Amazon.Lambda.Core and related dependencies to version 2.8.0 across source and test projects for improved Lambda compatibility and feature support (Directory.Packages.props, AWS.Lambda.Powertools.Parameters.csproj, AWS.Lambda.Powertools.Tracing.csproj, test props). [1] [2] [3] [4]
• Added the new concurrency test project to the solution file and ensured proper build configuration and nesting (AWS.Lambda.Powertools.sln). [1] [2] [3]

User experience

Please share what the user experience looks like before and after this change

Checklist

Please leave checklist items unchecked if they do not apply to your change.

• Meets tenets criteria
• I have performed a self-review of this change
• Changes have been tested
• Changes are documented
• PR title follows conventional commit semantics

Is this a breaking change?

RFC issue number:

Checklist:

• Migration process documented
• Implement warnings (if it can live side by side)

Acknowledgment

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Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[sonarqubecloud]

Quality Gate passed

Issues
12 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.24%. Comparing base (eff1550) to head (de9ceba).
⚠️ Report is 22 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1078      +/-   ##
===========================================
+ Coverage    78.18%   78.24%   +0.06%     
===========================================
  Files          298      298              
  Lines        12037    12045       +8     
  Branches      1449     1450       +1     
===========================================
+ Hits          9411     9425      +14     
+ Misses        2161     2156       -5     
+ Partials       465      464       -1     

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