action: add paths inputs, add example

README.md

@@ -6,3 +6,30 @@
                                                              
 **A generation utility for EuroScope Ground Radar and TopSky maps and settings using AIXM and KML.**
 
+## GitHub Action
+
+To run the mapbuilder GitHub action using a cache, see the following example:
+
+```yaml
+jobs:
+  build-maps:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Restore cached sources
+        uses: actions/cache/restore@v4
+        with:
+          path: .cache
+          key: sources
+      - name: Run mapbuilder
+        uses: vatger-nav/mapbuilder@main
+        with:
+          # defaults
+          target-path: '.'
+          source-path: 'mapdata'
+      - name: Store cached sources
+        uses: actions/cache/save@v4
+        with:
+          path: .cache
+          key: sources
+```

action.yml

@@ -2,14 +2,23 @@
 name: 'mapbuilder'
 author: 'vatger-nav'
 description: 'Builder for GRPlugin and Topsky maps'
+inputs:
+  target-path:
+    description: 'Target directory relative to repository root'
+    required: True
+    default: '.'
+  source-path:
+    description: 'Source directory with mapbuilder.toml relative to repository root'
+    required: True
+    default: 'mapdata'
 runs:
   using: 'docker'
   image: 'docker://ghcr.io/vatger-nav/mapbuilder:main'
   args:
     - '--debug'
     - '-s'
-    - '/github/workspace/mapdata'
-    - '/github/workspace'
+    - '/github/workspace/${{ inputs.source-path }}'
+    - '/github/workspace/${{ inputs.target-path }}'
 branding:
   icon: 'map'
   color: 'green'