Better server error messaging

[ahopkins]

Requires #3101
Resolves #3100

This has long been something that was less than clear: errors when starting with an already in use port.

This PR introduces a new pattern for catching some common startup issues and providing better display.

[Copilot]

Pull request overview

This PR improves server startup error handling by introducing a new error handling pattern that provides clearer, more user-friendly error messages for common startup issues like port conflicts. It addresses issues #3100 where errors were logged multiple times with confusing stack traces, and requires PR #3101 which upgrades tracerite.

Key changes:

• New error handler module provides clean error reporting for OSError and ServerError during startup
• Simplified socket configuration by removing nested error handling wrapper
• Better management of worker state and EOFError handling with conditional cleanup logic

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
sanic/startup/errors.py	New module introducing error handler pattern for startup failures with OSError and ServerError support
sanic/main.py	Integrates tracerite loading and wraps CLI execution with startup error handler
sanic/server/socket.py	Removes OSError wrapping logic, allowing errors to propagate to central handler
sanic/mixins/startup.py	Adds EOFError handling for Manager creation and tracks worker state to prevent cleanup issues
tests/test_startup_errors.py	New test suite covering all error handling scenarios
tests/test_exceptions_handler.py	Updates tests to accommodate tracerite HTML rendering changes
setup.py	Updates tracerite dependency to version 2.2.0 or higher
pyproject.toml	Adds ruff ignore rules for import ordering in main.py

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[Copilot]

@ahopkins I've opened a new pull request, #3106, to work on those changes. Once the pull request is ready, I'll request review from you.

[Tronic]

LGTM, works here - no more tracebacks shown. Thanks for the quick response!

[Tronic]

Maybe that's for another PR and pending another tracerite release, but one might consider also adding import tracerite; tracerite.load() early in Sanic init, making it print cleaner tracebacks on console as well. The module can be styled by setting color constants tracerite.tty.* This captures logging.exception as well (unless disabled by kwarg on load), overriding the custom exception styling that Sanic in dev mode is doing there.

[ahopkins]

I did put int in main.py, it would run only in CLI.

I went back and forth on this, but I think this is the right compromise. Happy to entertain other thoughts though.

[codecov]

Codecov Report

❌ Patch coverage is 75.00000% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.683%. Comparing base (f240432) to head (90369b7).
⚠️ Report is 15 commits behind head on main.

Files with missing lines	Patch %	Lines
sanic/mixins/startup.py	42.105%	10 Missing and 1 partial ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #3102       +/-   ##
=============================================
+ Coverage   87.643%   87.683%   +0.039%     
=============================================
  Files          103       104        +1     
  Lines         7729      7778       +49     
  Branches      1225      1236       +11     
=============================================
+ Hits          6774      6820       +46     
- Misses         660       662        +2     
- Partials       295       296        +1     

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