fix: type rawBody as optional since it can be undefined

[marceli1404]

Closes #174

The module augments koa.Request and http.IncomingMessage with rawBody: string, but at runtime the property is only assigned when a body is actually parsed — it remains undefined for unsupported content types, disabled parsers, closed requests, or when the request is skipped. With skipLibCheck: false (or in strict consumer projects) TypeScript reports rawBody as always a string, which is misleading and can hide runtime bugs.

Change

• koa.Request.rawBody → string | undefined (optional)
• http.IncomingMessage.rawBody → string | undefined (optional)

The existing test suite already asserts the undefined behavior (e.g. expect(ctx.request.rawBody).toEqual(undefined) in test/middleware.test.ts), so this only aligns the declared types with the implemented behavior.

Verification

• npm test: 34 passed
• npm run build (tsup + dts): success

Summary by Sourcery

Align type declarations of rawBody with its runtime behavior by making it optional on Koa and Node request objects.

Bug Fixes:

• Mark koa.Request.rawBody as an optional string to reflect that it may be undefined at runtime.
• Mark http.IncomingMessage.rawBody as an optional string to reflect that it may be undefined at runtime.

Summary by CodeRabbit

• Bug Fixes
  • Improved type compatibility by allowing the raw request body to be unavailable when it hasn’t been populated.

[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: 37eb25d9-69d0-43ad-92cc-c4c7961675f9

📥 Commits

Reviewing files that changed from the base of the PR and between b9b77aa and 277a495.

📒 Files selected for processing (1)

• src/body-parser.ts

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📝 Walkthrough

Walkthrough

The Koa Request and Node IncomingMessage module augmentations now declare rawBody as an optional string. This matches runtime behavior when no suitable body type is found.

🚥 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 clearly states that rawBody is now optional, which matches the primary change.
Linked Issues check	✅ Passed	The changes satisfy issue [#174] by declaring rawBody as optional where runtime behavior can produce undefined.
Out of Scope Changes check	✅ Passed	The pull request only updates rawBody declarations and contains no unrelated changes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

This pull request updates the TypeScript declaration of the rawBody property on koa.Request and http.IncomingMessage to be optional (string | undefined), aligning the types with actual runtime behavior where rawBody is only set when a body is parsed.

File-Level Changes

Change	Details	Files
Make rawBody optional in type declarations to match runtime behavior.	Change koa.Request.rawBody type from string to optional string Change http.IncomingMessage.rawBody type from string to optional string	src/body-parser.ts

Assessment against linked issues

Issue	Objective	Addressed	Explanation
#174	Update the TypeScript declaration for koa.Request.rawBody so that it reflects that rawBody can be undefined at runtime (i.e., make it optional or type it as string	undefined).	✅
#174	Update the TypeScript declaration for http.IncomingMessage.rawBody so that it reflects that rawBody can be undefined at runtime (i.e., make it optional or type it as string	undefined).	✅

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