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Debounce Search Input to Reduce API Calls

Wrap the search handler in a 300ms debounce so typing five characters fires one request not five.

~15 minperformancefrontenddebounce

Task

Apply const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); to reduce a measured bottleneck that shows up in the performance budget or Lighthouse audit.

When to use this

Lighthouse reports the page fails the performance budget because of const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300);, scoring 72 on mobile.

Prerequisites

  • A Lighthouse or WebPageTest baseline measurement
  • Access to the build configuration

Steps

1. Configure const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); in the project configuration file with the recommended defaults.

const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300);

Expected output: The configuration is accepted and const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); runs without errors on the first invocation.

2. Run the check locally to verify const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); 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 const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); blocks merge on failure.

- name: Run add debounce search input
  run: pnpm test

Expected output: Pull requests with failing const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300); 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.

Measure before optimizing

Start by measuring the problem. Wrap the search handler in a 300ms debounce so typing five characters fires one request not five. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run const onSearch = debounce((q) => fetch(/api/search?q=${q}), 300); against the current codebase and inspect the output before wiring it into CI.

const onSearch = debounce((q) => fetch(`/api/search?q=${q}`), 300);

Verify the improvement

Once the gate is in place, make failures actionable. A failing const onSearch = debounce((q) => fetch(/api/search?q=${q}), 300); 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.