Rate Limit with a Redis Token Bucket
Implement a token bucket in Redis so distributed rate limiting works across multiple instances with atomic decrements.
Task
Implement INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 to close a known attack surface before the next security review finds it.
When to use this
A penetration test report flags the missing INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 as a medium-severity finding on a public endpoint.
Prerequisites
- A running application with the vulnerable endpoint
- Access to security headers or middleware config
Steps
1. Configure INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 in the project configuration file with the recommended defaults.
INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60
Expected output: The configuration is accepted and INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 runs without errors on the first invocation.
2. Run the check locally to verify INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 produces the expected result before pushing.
pnpm test
Expected output: Local run matches CI behavior; no surprises after push.
3. Add the gate to the CI pipeline so INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 blocks merge on failure.
- name: Run add rate limit redis token bucket
run: pnpm test
Expected output: Pull requests with failing INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 are blocked from merging.
Troubleshooting
Problem
The check passes locally but fails in CI
Solution
Pin dependency versions and the runtime to match CI exactly; reproduce with the same Docker image or act.
Problem
Configuration is rejected with a schema error
Solution
Check the tool version matches the config schema; older versions may not support newer fields.
Limitations
- The gate only runs on events that trigger the workflow; locally pushed commits bypass it.
- Configuration drift is possible if someone edits settings outside version control.
Close the attack surface
Start by measuring the problem. Implement a token bucket in Redis so distributed rate limiting works across multiple instances with atomic decrements. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 against the current codebase and inspect the output before wiring it into CI.
INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60Verify and monitor
Once the gate is in place, make failures actionable. A failing INCR rate:bucket:user123 && EXPIRE rate:bucket:user123 60 should point to the exact file and line, not a generic error. Pin the tool version in the lockfile so a upstream release does not silently change behavior. Review the gate output in every pull request just like a test result.