feat: add configurable cache key with template variable support (#246)

I closed [this PR](#235) by
mistake so I'm reopening it.

Author: pepicrft

.github/workflows/test.yml

@@ -105,6 +105,23 @@ jobs:
           exit 1
         if: ${{ steps.bad.outcome != 'failure' }}
 
+  custom_cache_key:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+      - name: Setup mise with custom cache key
+        uses: ./
+        with:
+          cache_key: "custom-{{platform}}-{{install_args_hash}}-${{ github.run_id }}"
+          install_args: "jq@1.7.1"
+          mise_toml: |
+            [tools]
+            jq = "1.7.1"
+      - run: mise --version
+      - run: mise x jq -- jq --version
+      - run: which jq
+      - run: jq --version
+
   fetch_from_github:
     runs-on: ubuntu-latest
     steps:

README.md

@@ -42,6 +42,58 @@ jobs:
       - run: node ./my_app.js
 ```
 
+## Cache Configuration
+
+You can customize the cache key used by the action:
+
+```yaml
+- uses: jdx/mise-action@v2
+  with:
+    cache_key: "my-custom-cache-key"  # Override the entire cache key
+    cache_key_prefix: "mise-v1"       # Or just change the prefix (default: "mise-v0")
+```
+
+### Template Variables in Cache Keys
+
+When using `cache_key`, you can use template variables to reference internal values:
+
+```yaml
+- uses: jdx/mise-action@v2
+  with:
+    cache_key: "mise-{{platform}}-{{version}}-{{file_hash}}"
+    version: "2024.10.0"
+    install_args: "node python"
+```
+
+Available template variables:
+- `{{version}}` - The mise version (from the `version` input)
+- `{{cache_key_prefix}}` - The cache key prefix (from `cache_key_prefix` input or default)
+- `{{platform}}` - The target platform (e.g., "linux-x64", "macos-arm64")
+- `{{file_hash}}` - Hash of all mise configuration files
+- `{{mise_env}}` - The MISE_ENV environment variable value
+- `{{install_args_hash}}` - SHA256 hash of the sorted tools from install args
+- `{{default}}` - The processed default cache key (useful for extending)
+
+Conditional logic is also supported using Handlebars syntax like `{{#if version}}...{{/if}}`.
+
+Example using multiple variables:
+```yaml
+- uses: jdx/mise-action@v2
+  with:
+    cache_key: "mise-v1-{{platform}}-{{install_args_hash}}-{{file_hash}}"
+    install_args: "node@20 python@3.12"
+```
+
+You can also extend the default cache key:
+```yaml
+- uses: jdx/mise-action@v2
+  with:
+    cache_key: "{{default}}-custom-suffix"
+    install_args: "node@20 python@3.12"
+```
+
+This gives you full control over cache invalidation based on the specific aspects that matter to your workflow.
+
 ## GitHub API Rate Limits
 
 When installing tools hosted on GitHub (like `gh`, `node`, `bun`, etc.), mise needs to make API calls to GitHub's releases API. Without authentication, these calls are subject to GitHub's rate limit of 60 requests per hour, which can cause installation failures.

action.yml

@@ -45,6 +45,12 @@ inputs:
     required: false
     default: "mise-v0"
     description: The prefix key to use for the cache, change this to invalidate the cache
+  cache_key:
+    required: false
+    description: |
+      Override the complete cache key (ignores all other cache key options).
+      Supports template variables: {{version}}, {{cache_key_prefix}}, {{platform}}, {{file_hash}}, 
+      {{mise_env}}, {{install_args_hash}}, {{default}} and conditional logic like {{#if version}}...{{/if}}
   experimental:
     required: false
     default: "false"