use cache in action

action.yml

@@ -40,6 +40,20 @@ inputs:
     description: Version of the action container to run
     deprecationMessage: No longer used. github.action_ref replaces the need for this. Will be removed in a future version.
     required: false
+  enable_cache_dnf: 
+    description: Whether to enable caching for dnf
+    required: false
+    default: "true"
+  enable_cache_skopeo:
+    description: Whether to enable caching for skopeo
+    required: false
+    default: "true"
+  dnf_cache_key:
+    description: Overrides the dnf cache key
+    required: false
+  skopeo_cache_key:
+    description: Overrides the skopeo cache key
+    required: false
   additional_templates:
     description: Space delimetered list of additional Lorax templates to include
     required: false
@@ -47,12 +61,32 @@ inputs:
 runs:
   using: composite
   steps:
+    - name: Load dnf cache
+      env:
+        dnf_cache_key: dnf-${{ inputs.version }}
+      if: inputs.enable_cache_dnf == 'true'
+      uses: action/cache/restore@v4
+      with:
+        path: /cache/dnf
+        key: ${{ inputs.dnf_cache_key || env.dnf_cache_key }}
+
+    - name: Load skopeo cache
+      env:
+        skopeo_cache_key: skopeo-${{ inputs.image_name }}-${{ inputs.image_tag }}
+      if: inputs.enable_cache_skopeo == 'true'
+      uses: action/cache/restore@v4
+      with:
+        path: /cache/skopeo
+        key: ${{ inputs.skopeo_cache_key || env.skopeo_cache_key }}
+
     - name: Run docker image
       shell: bash
       run: |
         # Check if running inside of the action repo
         if [[ -z "${{ github.action_ref }}" ]]; then if [[ "${{ github.ref_name }}" =~ (.*)/merge ]]; then tag=pr-${BASH_REMATCH[1]}; else tag=${{ github.ref_name }}; fi; fi
         if [[ -z "${tag}" ]]; then tag=${{ github.action_ref }}; fi
+        if [[ "${{ inputs.enable_cache_dnf }}" == "true" ]]; then cache="${cache} -v /cache/dnf:/cache/dnf"; fi
+        if [[ "${{ inputs.enable_cache_skopeo }}" == "true" ]]; then cache="${cache} -v /cache/skopeo:/cache/skopeo"; fi
         docker run --privileged --volume ${{ github.workspace }}:/github/workspace/ ghcr.io/jasonn3/build-container-installer:${tag} \
           ARCH=${{ inputs.arch }} \
           IMAGE_NAME=${{ inputs.image_name }} \
@@ -63,5 +97,24 @@ runs:
           WEB_UI=${{ inputs.web_ui }} \
           ENROLLMENT_PASSWORD=${{ inputs.enrollment_password }} \
           SECURE_BOOT_KEY_URL=${{ inputs.secure_boot_key_url }} \
-          "ADDITIONAL_TEMPLATES=${{ inputs.additional_templates }}"
+          "ADDITIONAL_TEMPLATES=${{ inputs.additional_templates }}" \
+          DNF_CACHE=/cache/dnf
+
+    - name: Save dnf cache
+      env:
+        dnf_cache_key: dnf-${{ inputs.version }}
+      if: inputs.enable_cache_dnf == 'true'
+      uses: action/cache/save@v4
+      with:
+        path: /cache/dnf
+        key: ${{ inputs.dnf_cache_key || env.dnf_cache_key }}
+
+    - name: Save skopeo cache
+      env:
+        skopeo_cache_key: skopeo-${{ inputs.image_name }}-${{ inputs.image_tag }}
+      if: inputs.enable_cache_skopeo == 'true'
+      uses: action/cache/save@v4
+      with:
+        path: /cache/skopeo
+        key: ${{ inputs.skopeo_cache_key || env.skopeo_cache_key }}