fix: pass Koa response to setHeaders

[vibhor-aggr]

Fixes #130.

Summary

• Pass Koa's ctx.response object to the setHeaders callback instead of the raw Node response.
• Update the SetHeaders type and README wording to describe the Koa response argument.
• Update the existing setHeaders regression test to use Koa response methods such as response.set() and response.get().

Root Cause

setHeaders was receiving ctx.res, which requires callers to bypass Koa's response abstraction and use raw Node response methods. Koa documents that bypassing Koa's response handling is unsupported, and callers commonly need Koa response helpers when deciding whether to set cache headers.

Validation

• npx jest test/index.test.ts --runInBand --testNamePattern='setHeaders'
• npm test
• npm run lint (passes with the existing send complexity warning)
• npm run build
• git diff --check

Summary by Sourcery

Route Koa send header injection through the Koa response abstraction instead of the raw Node response, and align types, docs, and tests with the updated callback signature.

Bug Fixes:

• Ensure the setHeaders callback receives Koa's response object rather than the underlying Node response to avoid unsupported response handling.

Enhancements:

• Update the SetHeaders type to reference ParameterizedContext['response'] and rename its first parameter for clarity.

Documentation:

• Clarify README setHeaders documentation to describe the callback as receiving the Koa response object and update argument naming accordingly.

Tests:

• Adjust the setHeaders regression test to use Koa response helpers (set/get) and assert that the callback receives ctx.response.

Summary by CodeRabbit

• Bug Fixes

  • Updated the setHeaders callback to provide Koa’s response object, enabling standard response methods such as set() and get().
  • Preserved existing header protections and behavior, including preventing Content-Length overrides.

• Documentation

  • Clarified the setHeaders callback signature and response parameter in the documentation.

[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

Passes Koa's high-level response object into the setHeaders callback instead of the raw Node response, and aligns types, tests, and documentation with this behavior.

Sequence diagram for updated setHeaders invocation in send

sequenceDiagram
  participant KoaMiddleware
  participant send
  participant SetHeaders
  participant KoaResponse

  KoaMiddleware->>send: send(ctx, root, options)
  send->>SetHeaders: setHeaders(ctx.response, filePath, stats)
  send->>KoaResponse: set(Content-Length, stats.size)
  send->>KoaResponse: set(Last-Modified, stats.mtime.toUTCString())

Loading

File-Level Changes

Change	Details	Files
Route setHeaders to use Koa's ctx.response abstraction instead of the raw Node response.	Change send implementation to call setHeaders with ctx.response rather than ctx.res. Update SetHeaders type signature to accept ParameterizedContext['response']. Ensure header setting and retrieval logic uses Koa response helpers rather than Node response APIs.	src/send.ts src/send.types.ts
Align tests and README with the new Koa response-based setHeaders contract.	Update the regression test to assert it receives ctx.response and uses response.set()/response.get() instead of res.setHeader(). Adjust README examples and wording to document fn(response, path, stats) and describe response as the Koa response object.	test/index.test.ts README.md

Assessment against linked issues

Issue	Objective	Addressed	Explanation
#130	Change the first parameter passed to the setHeaders option from the raw Node response (ctx.res) to the Koa response (ctx.response) in the implementation and types.	✅
#130	Update tests and documentation to reflect that setHeaders now receives the Koa response object and demonstrate using Koa response methods.	✅

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: b351b01b-9509-490e-940a-041c1876a222

📥 Commits

Reviewing files that changed from the base of the PR and between 09657fc and b280945.

📒 Files selected for processing (4)

• README.md
• src/send.ts
• src/send.types.ts
• test/index.test.ts

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📝 Walkthrough

Walkthrough

The setHeaders callback now receives ctx.response instead of ctx.res. Its internal type references Koa’s response property, tests use response.set() and response.get(), and documentation describes the updated callback signature. Existing header behavior, including protection of Content-Length, remains covered.

🚥 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 accurately summarizes the main change: passing Koa's response object to setHeaders.
Linked Issues check	✅ Passed	The PR satisfies #130 by changing setHeaders to receive Koa's response object and updating types, docs, and tests accordingly.
Out of Scope Changes check	✅ Passed	The changes are tightly scoped to the setHeaders response-object update and its supporting documentation and tests.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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