Filtering Files

Mint caches tasks based on the contents of the file system (docs on caching). However, some tasks may only need to use a subset of the files. When defining a Mint task, you can add a filter so that only the specified files will be present on disk. This will result in more frequent cache hits.


  - key: write-files
    run: |
      echo ${{ }} | tee changes-every-time.txt
      echo static file contents | tee stays-the-same.txt
  - key: hash-files
    use: [write-files]
    run: sha256sum *.txt
  - key: hash-static-files
    use: [write-files]
      - stays-the-same.txt
    run: sha256sum *.txt

The output of hash-files will look like this:

09ebb220c8a4997acd2b9f9f99aaf200d9861b689ffcc26a3cd10c15efead761  changes-every-time.txt
672939a0624c8c668ffa85ea007e600e3c4ba503dfcf00ca1b603b7cb5c6c56b  stays-the-same.txt

The output of hash-static-files will look like this:

672939a0624c8c668ffa85ea007e600e3c4ba503dfcf00ca1b603b7cb5c6c56b  stays-the-same.txt

And if you run these tasks again, write-files and hash-files will always produce a cache miss, whereas hash-static-files will always produce a cache hit!


Mint uses the contents of the entire file system for determining the cache key. However, the filter only applies to the workspace directory, which is /var/mint-workspace. If any files change outside of the workspace, such as with system dependencies or configuration, it'll always result in a different cache key.