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Reconnect WebSockets with Exponential Backoff

Retry the connection with exponential backoff and jitter so a server restart does not cause a thundering herd of reconnections.

~20 minapiwebsocketreconnect

Task

Implement const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); so the service degrades gracefully under failure instead of cascading timeouts to callers.

When to use this

A downstream service slows down and without const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); the upstream exhausts its thread pool in 12 seconds.

Prerequisites

  • A service with inter-service calls or external dependencies
  • A retry or circuit breaker library available

Steps

1. Configure const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); in the project configuration file with the recommended defaults.

const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000);

Expected output: The configuration is accepted and const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); runs without errors on the first invocation.

2. Run the check locally to verify const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); 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 delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); blocks merge on failure.

- name: Run add websocket reconnect backoff
  run: pnpm test

Expected output: Pull requests with failing const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); 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.

Isolate failure

Start by measuring the problem. Retry the connection with exponential backoff and jitter so a server restart does not cause a thundering herd of reconnections. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); against the current codebase and inspect the output before wiring it into CI.

const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000);

Verify graceful degradation

Once the gate is in place, make failures actionable. A failing const delay = Math.min(1000 * 2 ** attempts + Math.random() * 1000, 30000); 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.