Wait for HTTPS listener readiness in integration tests

[Copilot]

Description

The real HTTPS listener test could issue its first request before Kestrel accepted connections, causing intermittent macOS failures.

• Listener readiness
  • Probe the loopback port after OpenAsync.
  • Retry connection failures every 25 ms with a 10-second deadline.
  • Create the test client only after the listener accepts TCP connections.

Related Issues

Checklist

• I have signed the CLA and read the CONTRIBUTING doc.
• I have added tests that prove my fix is effective or that my feature works and increased code coverage.
• I have added all necessary documentation.
• I have verified that my changes do not introduce (new) build or analyzer warnings.
• I ran all tests locally using the UA.slnx solution against at least .net framework and .net 10, and all passed.
• I fixed all failing and flaky tests in the CI pipelines and all CodeQL warnings.
• I have addressed all PR feedback received.

• Fixes Opc.Ua.Bindings.Https.WebApi.Tests: RepublishCompactOverRealHttpsListener flakes on macOS #4307

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1 out of 2 committers have signed the CLA.

✅ marcschier
❌ Copilot
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[marcschier]

/azp run

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[Copilot]

Pull request overview

This PR hardens the RealHttpsListenerIntegrationTests fixture by ensuring the Kestrel-backed HTTPS listener is actually accepting TCP connections before the first test request is sent, addressing an intermittent macOS flake in the real HTTPS round-trip tests.

Changes:

• Added a post-OpenAsync readiness probe that attempts loopback TCP connects until the listener accepts or a deadline is reached.
• Deferred HttpClient creation until after listener readiness is confirmed.

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[github-actions]

Code coverage

✅ Coverage gate passed.

Check	Result	Threshold
✅ Project line rate	86.14% (233344/270884 lines)	>= 70.00%
✅ Project branch rate	75.60%	>= 60.00%
ℹ️ Patch coverage	no changed C# files	-
ℹ️ Baseline delta (advisory)	+12.54 pp	73.60% recorded

Coverage is above the recorded baseline - consider ratcheting coverage-thresholds.json.

_{Thresholds live in coverage-thresholds.json. Whole report before exclusions: line 85.51%, branch 75.05%.}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.30%. Comparing base (cb50353) to head (99bb998).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4313      +/-   ##
==========================================
- Coverage   80.30%   80.30%   -0.01%     
==========================================
  Files        1927     1927              
  Lines      263492   263492              
  Branches    46101    46101              
==========================================
- Hits       211597   211590       -7     
- Misses      35650    35669      +19     
+ Partials    16245    16233      -12     

Flag	Coverage Δ
actions	80.30% <ø> (-0.01%)	⬇️

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see 31 files with indirect coverage changes

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[marcschier]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).

[marcschier]

@copilot fix ci

[Copilot]

@copilot fix ci

Fixed in 99bb998 by removing the unused exception variable that caused CS0168 in the HTTPS WebApi test build. Targeted dotnet test tests/Opc.Ua.Bindings.Https.WebApi.Tests/Opc.Ua.Bindings.Https.WebApi.Tests.csproj -f net10.0 --no-restore passes.