Fix 6 issues: WithBody matching, ILoggerFactory overloads, thread safety, fire-and-forget fix, terminal methods return IRequestStub

[Copilot]

Summary

Fixes all 6 issues identified in the prior review session. The package version remains at 3.0.0. To publish to NuGet, create a GitHub release tagged v3.0.0 — this triggers the publish.yml workflow which builds, tests, packs and pushes both HttpMock and HttpMock.Verify.NUnit.

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Changes

1. IRequestStub terminal methods now return IRequestStub

OK(), NotFound(), and WithStatus() previously returned void, preventing any fluent chaining after the status call. They now return this, making chains like .OK().WithDelay(500) valid. This also fixes the broken WithDelay example in the README.

2. Request body matching for stubs (WithBody)

Added WithBody(string) and WithBody(Func<string, bool>) to IRequestStub / RequestHandler. The request body is now buffered synchronously in RequestProcessor.OnRequest (before matching) and passed down to HandleRequest as a pre-read string. RequestMatcher.Match filters by IRequestHandler.MatchesBody() alongside the existing URL / header / query checks — allowing multiple stubs on the same path+method to be distinguished by body content.

3. HttpMockRepository.At with ILoggerFactory

Added At(string, ILoggerFactory) and At(Uri, ILoggerFactory) overloads to HttpMockRepository, HttpServerFactory, and IHttpMockRepository. The logger flows through to HttpServer and RequestProcessor.

4. Silent fire-and-forget exception loss fixed

HandleRequest task is now chained with .ContinueWith(t => _log.LogError(t.Exception?.InnerException ?? t.Exception, ...), OnlyOnFaulted) so any exception after an await is logged rather than silently swallowed.

5. HttpServerFactory thread safety

Replaced bare Dictionary access with a private readonly object _serverLock + lock blocks. The Get method atomically checks availability and creates the server under the lock, preventing races when multiple tests share the same static factory.

6. README fixes

• HttpMockRepository.At("...", loggerFactory) example is now backed by a real overload.
• WithDelay chaining example after OK() is now valid (see fix 1).
• New Matching by Request Body section documents WithBody.

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Tests

• 7 new integration tests in StubBodyConstraintTests.cs covering exact-string match, predicate match, multi-stub disambiguation by body, no-constraint fallback, and the At logger-factory overload.
• RequestMatcherTests updated to stub the new MatchesBody member on mocked IRequestHandler.
• 35 unit tests + 69 integration tests — all pass.

[hibri]

@copilot why is this 4096?

[Copilot]

The 4096 was a leftover from when the code used the 5-argument constructor overload (new StreamReader(stream, encoding, detectBom, bufferSize, leaveOpen: true)) — leaveOpen: true was needed because the stream was passed further downstream at the time. Once we switched to leaveOpen: false (the default), the full overload was no longer needed. 4096 is also just the default StreamReader internal buffer size, so specifying it explicitly was redundant noise.

Simplified to new StreamReader(requestBody, Encoding.UTF8) in 41454f1.