fix(backend): correct middleware order so optional auth executes before rate limiter (fix #136)

[Pratyush-Panda-2006]

Description

This pull request resolves a critical middleware registration ordering issue in the backend entry point. Previously, the rateLimiter middleware was loaded before optionalAuthenticateUser processed incoming requests. Since Express executes middlewares in sequential registration order, req.user was not yet populated when the rate limiter ran, preventing it from obtaining the user's _id and forcing it to default to IP-based limits for all API calls.

Changes

• Reordered the app.use statements in backend/src/server.js to execute optionalAuthenticateUser prior to rateLimiter.

Fixes #136

[coderabbitai]

Warning

Review limit reached

@Pratyush-Panda-2006, you've reached your PR review limit, so we couldn't start this review.

Next review available in: 48 minutes

Enable usage-based reviews in Billing to review now. Otherwise, wait until the next included review is available.
You're only billed for reviews past your plan's rate limits ($0.25/file).

How can I continue?

After more reviews become available, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

To avoid repeated limits, reduce automatic review volume by pausing incremental auto-reviews earlier, using label-based review opt-in, excluding WIP or generated PR titles, or requesting reviews manually when the PR is ready. If your team needs uninterrupted high-volume reviews, an organization admin can enable usage-based reviews.

How do review limits work?

CodeRabbit enforces per-developer PR review limits for each organization. Most developers receive the normal plan review availability.

For paid Pro and Pro+ PR reviews, CodeRabbit uses adaptive limits for sustained high-volume activity. When a developer's recent PR review activity reaches the 95th percentile or higher among CodeRabbit users, additional reviews become available more gradually as earlier reviews age out of the rolling window.

Please refer docs for additional details.

Review details

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 980c5d6b-8bca-42ad-925a-eb6489e79862

📥 Commits

Reviewing files that changed from the base of the PR and between a3fcb95 and 0a9acfd.

📒 Files selected for processing (2)

• backend/src/server.js
• github_issues.md

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}