add readme

README.md

@@ -0,0 +1,66 @@
+## @unisonweb/actions/stack/install
+Installs `stack` and adds it to the path.
+
+Example usage:
+```
+steps:
+  - uses: unisonweb/actions/stack/install@main
+    with:
+      version: 2.9.1
+```      
+`version` is optional.
+
+## @unisonweb/actions/stack/cache/restore
+Restore the global and local stack work directories from a cache
+
+Example usage:
+```
+steps:
+  - name: restore stack caches
+    id: restore-stack-caches
+    uses: unisonweb/actions/stack/cache/restore@main
+    with:
+      cache-prefix: ci
+
+  - name: check result
+    if: steps.restore-stack-caches.outputs.cache-hit == 'true'
+    run: echo "Found an exact match!"
+    shell: bash
+```
+
+The caches are keyed by the cache prefix, the OS, and the resolver version in your `stack.yaml`, and the contents of your `stack.yaml` and `package.yaml`.
+
+For a partial hit, only the cache prefix, the OS, and the resolver version must match, so you can use the `cache-prefix` input to distinguish between caches you wouldn't want to use as fallbacks, even if the OS and resolver match.
+
+### Inputs
+`cache-prefix`: The cache prefix to use for `~/.stack`, e.g. "release" or "ci". Required.
+`work-cache-prefix`: The cache prefix to use for `**/.stack-work`. Defaults to the same as `cache-prefix`.
+`stack-yaml-dir`: The directory to search for `stack.yaml`. Defaults to `"."`
+`lookup-only`: If `'true'`, only checks if cache entry exists and skips download. Defaults to `'false'`. Note that due to technical limitations, these are strings, not Booleans.
+
+### Outputs
+`cache-hit`: Whether the `.stack` cache was restored with an exact match.
+`work-cache-hit`: `'true'` or `'false'`, whether the `.stack-work` cache was restored with an exact match. Note that due to technical limitations, these are strings, not Booleans.
+
+## @unisonweb/actions/stack/cache/save
+Save the global and local stack work directories to caches.
+
+Due to a technical limitation, these actions provide independent `restore` and `save` functionality. This is in contrast to the `github/actions/cache` action which automatically saves at the end of a succesful run, whenever there was not an exact cache hit during restore.
+
+Instead, you have to do this manually: restoring at the start, and saving at the end whenever there was not an exact cache hit during restore.
+
+Example usage:
+```
+steps:
+  - name: save stack caches
+    if: steps.restore-stack-caches.outputs.cache-hit != 'true'
+    uses: unisonweb/actions/stack/cache/save@main
+    with:
+        cache-prefix: ci
+```
+
+### Inputs
+`cache-prefix`: The cache prefix to use for `~/.stack`, e.g. "release" or "ci". Required.
+`work-cache-prefix`: The cache prefix to use for `**/.stack-work`. Defaults to the same as `cache-prefix`.
+`stack-yaml-dir`: The directory to search for `stack.yaml`. Defaults to `"."`
+`lookup-only`: If `'true'`, only checks if cache entry exists and skips download. Defaults to `'false'`. Note that due to technical limitations, these are strings, not Booleans.

stack/install/action.yaml

@@ -8,7 +8,7 @@ inputs:
   stack-version:
     description: "The version of stack to install, e.g. 2.9.1"
     required: true
-    default: "2.9.1"
+    default: 2.9.1
 
 runs:
   using: "composite"