actions/cache "Path Validation Error" / some paths not resolved in CI
actions/cache resolves each path glob before saving. If none of the patterns match any files, it errors with "Path Validation Error: Path(s) specified in the action do not exist, hence no cache is being saved." The directory was never created by the time the post step ran.
What this error means
The post step fails or warns with "Path Validation Error: Path(s) specified in the action do not exist, hence no cache is being saved", naming a path that was expected to hold dependencies.
Warning: Path Validation Error: Path(s) specified in the action do not exist, hence no cache is being saved.Common causes
The cached directory is created later or never
You cache ~/.cache/pip but the install that populates it ran in a different step, container, or working directory, so the path is empty at save time.
A wrong or platform-specific path in the glob
The configured path does not match where the tool actually writes its cache on this runner OS, so the glob resolves to nothing.
How to fix it
Point path at the real cache location
- Run the package manager once to learn its cache dir (for example
npm config get cache). - Set
pathto that exact directory. - Ensure the install step runs and populates it before the post (save) step.
- uses: actions/cache@v4
with:
path: ~/.npm
key: npm-${{ runner.os }}-${{ hashFiles('**/package-lock.json') }}
- run: npm ciUse the per-OS path the tool reports
Cache directories differ by OS (for example ~/.cache/pip on Linux vs ~/Library/Caches/pip on macOS). Use the tool's reported path or a matrix-aware value so the glob always resolves.
How to prevent it
- Confirm the exact cache directory the tool uses per OS.
- Populate the path before the cache save step runs.
- Avoid caching directories that may not exist on a clean run.