Debug-action-cache Official

An essential part of the actions/cache logic is its cache-hit output variable. You can use this in conditional steps with if: statements.

- name: Attempt Cache Restore with Full Debug uses: actions/cache@v4 with: path: node_modules key: debug-$ runner.os -$ steps.sim.outputs.hash restore-keys: debug-$ runner.os -

: Provides a raw look at the current state of the local action cache. Common Troubleshooting Steps debug-action-cache

UUID generators or random seed sorting used during code generation. 2. Under-Declaration of Dependencies

Print the hash of your lockfile at the very beginning of your job, and compare it across different runs. An essential part of the actions/cache logic is

Logging the exact PATH and CHECKSUM used to generate the cache key.

The debug-action-cache is not just a tool; it's an essential debugging mindset for any serious GitHub Actions user. By enabling verbose logging, you transform the opaque process of caching into an open, transparent, and fully observable system. You gain the power to diagnose every failure—from silent version mismatches to confusing path errors and hidden quota limits—with precision and confidence. Common Troubleshooting Steps UUID generators or random seed

While caching drastically reduces execution time, it introduces a major point of failure: state persistence. If a cache becomes corrupted, poisoned with bad data, or locked due to permissions errors, subsequent builds will inherit those defects. This results in "flaky builds"—pipelines that fail or succeed unpredictably without any changes to the source code. Common Scenarios Requiring Cache Debugging

GitHub repo → Settings → Secrets and variables → Actions → New repository secret