docs: fix documentation drift

[chimurai]

Summary by CodeRabbit

• Documentation
  • Documented IPv6 unspecified hostname target handling and normalization
  • Updated router callback documentation with parameter signatures for string and object targets
  • Clarified WebSocket upgrade requirements and middleware behavior across multiple servers
  • Enhanced Node.js 17+ IPv6 configuration notes

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 7f448341-e6cc-431c-b8bd-839c95a704b8

📥 Commits

Reviewing files that changed from the base of the PR and between 39a47ab and 1d5eaec.

📒 Files selected for processing (4)

• CHANGELOG.md
• README.md
• recipes/router.md
• recipes/websocket.md

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📝 Walkthrough

Walkthrough

This PR updates documentation and changelog entries to describe three related changes: router callbacks now accept (req, res, options) with res undefined during WebSocket upgrades; WebSocket upgrade subscriptions require an initial HTTP request and separate requests per server; and unspecified IPv6 hosts like [::]:port normalize to ::1.

Changes

Documentation Updates

Layer / File(s)	Summary
Router API signature and examples README.md, recipes/router.md	Router callback examples updated to show (req, res, options) signature in both string-target and object-target forms; async router and custom router recipe examples demonstrate parameter shape; note clarifies res is undefined during WebSocket upgrade flows.
WebSocket upgrade requirements and multi-server notes README.md, recipes/websocket.md	Documentation clarified that an initial HTTP request is required to subscribe to server upgrade events, and that middleware attached to multiple servers requires a separate initial HTTP request per server for upgrade subscription activation.
IPv6 unspecified host normalization CHANGELOG.md, README.md	Changelog entry added for IPv6 fix; README notes document that unspecified IPv6 hosts like http://[::]:port normalize to ::1 for local listeners.

Possibly related PRs

• chimurai/http-proxy-middleware#1244: Implements the router API changes (req, res, options signature) in source code that this PR's documentation describes.
• chimurai/http-proxy-middleware#1234: Implements the IPv6 unspecified hostname normalization fix in src/utils/ipv6.ts that this PR documents.
• chimurai/http-proxy-middleware#1238: Updates WebSocket documentation with overlapping changes to recipes/websocket.md and WebSocket upgrade guidance.

Poem

🐰 A rabbit hops through docs so fine,
Routing requests, one line at a line,
WebSocket notes shine crisp and clear,
IPv6 paths—the way is here! ✨

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🎯 1 (Trivial) | ⏱️ ~3 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'docs: fix documentation drift' directly and accurately describes the main change in the pull request, which consists entirely of documentation updates across multiple markdown files (CHANGELOG.md, README.md, recipes/router.md, recipes/websocket.md) to align documentation with current functionality.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch update-documentation-drift

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[pkg-pr-new]

npm i https://pkg.pr.new/http-proxy-middleware@1248

commit: 1d5eaec

[coveralls]

coverage: 94.656%. remained the same — update-documentation-drift into master