Build versions and tag them

.github/workflows/watch.yml

@@ -0,0 +1,37 @@
+name: Watch
+
+on:
+  schedule:
+    - cron: '30 */4 * * *'
+  push: ~
+
+jobs:
+  docker:
+    name: Push tagged docker image
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+        with:
+          ref: master
+
+      - name: Update Dockerfile with latest version
+        id: fetch_version
+        run: |
+          last=$(curl -s https://packagist.org/packages/vimeo/psalm.json|jq '[.package.versions[]|select(.version|test("^\\d+\\.\\d+\\.\\d+$"))|.version]|max_by(.|[splits("[.]")]|map(tonumber))')
+          last=$(echo $last | tr -d '"')
+          echo "Last Psalm version is $last"
+          echo ::set-output name=last::$last
+
+          sed -i -re "s/require vimeo\/psalm/require vimeo\/psalm:$last/" Dockerfile
+          cat Dockerfile
+
+      - name: Docker login
+        run: echo '${{ secrets.DOCKER_PASSWORD }}' | docker login --username ${{ secrets.DOCKER_USERNAME }} --password-stdin
+
+      - name: Build images
+        run: docker build -t vimeo/psalm-github-actions:${{ steps.fetch_version.outputs.last }} .
+
+      - name: Publish
+        run: docker push vimeo/psalm-github-actions:${{ steps.fetch_version.outputs.last }}

Dockerfile

@@ -26,7 +26,7 @@ ADD https://github.com/vimeo/psalm/commits/master.atom /dev/null
 
 RUN COMPOSER_ALLOW_SUPERUSER=1 \
     COMPOSER_HOME="/composer" \
-    composer global require --prefer-dist --no-progress --dev vimeo/psalm
+    composer global require vimeo/psalm --prefer-dist --no-progress --dev
 
 ENV PATH /composer/vendor/bin:${PATH}
 

README.md

@@ -19,3 +19,11 @@ jobs:
         uses: docker://vimeo/psalm-github-actions
 
 ```
+
+You can also specify a version (after 3.14.2).
+
+```diff
+       - name: Psalm
+-        uses: docker://vimeo/psalm-github-actions
++        uses: docker://vimeo/psalm-github-actions:3.14.2
+```