Add reusable workflow for setting up SSH agent

.github/actions/ssh/action.yml

@@ -0,0 +1,29 @@
+name: Set up SSH agent
+description: Set up the SSH agent
+author: Tobi Schäfer <tobi@antville.org>
+
+inputs:
+  config:
+    description: The SSH configuration
+    required: true
+  key:
+    description: The private SSH key
+    required: true
+  known-hosts:
+    description: The list of known hosts
+    required: true
+
+runs:
+  using: composite
+
+  steps:
+    - name: Set up SSH agent
+      shell: bash
+      run: |
+        socket=/tmp/ssh-agent.sock
+        echo "SSH_AUTH_SOCKET=$socket" >> $GITHUB_ENV
+        ssh-agent -a $socket > /dev/null
+        ssh-add - <<< '${{ inputs.key }}'
+        mkdir -p ~/.ssh
+        echo '${{ inputs.config }}' > ~/.ssh/config
+        echo '${{ inputs.known-hosts }}' > ~/.ssh/known_hosts

.github/workflows/stage.yml

@@ -1,10 +1,10 @@
 name: Deploy (Staging)
 
 on:
-  workflow_dispatch
-
-env:
-  SSH_AUTH_SOCK: /tmp/ssh-agent.sock
+  workflow_dispatch: {}
+  push:
+    branches:
+      - helma-🐜
 
 jobs:
   stage:
@@ -17,34 +17,13 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up Java
-        uses: actions/setup-java@v4
-        with:
-          distribution: temurin
-          java-version: 21
-
-      - name: Set up Gradle
-        uses: gradle/actions/setup-gradle@v3
-
-      - name: Build with Gradle
-        run: ./gradlew installDist
-
       - name: Set up SSH agent
-        run: |
-          ssh-agent -a $SSH_AUTH_SOCK > /dev/null
-          ssh-add - <<< "${{ secrets.SSH_PRIVATE_KEY }}"
-          mkdir -p ~/.ssh
-          echo '${{ vars.SSH_CONFIG }}' > ~/.ssh/config
-          echo '${{ vars.KNOWN_HOSTS }}' > ~/.ssh/known_hosts
+        uses: ./.github/actions/ssh
+        with:
+          config: ${{ vars.SSH_CONFIG }}
+          key: ${{ secrets.SSH_PRIVATE_KEY }}
+          known-hosts: ${{ vars.SSH_KNOWN_HOSTS }}
 
-      - name: Publish to staging server
+      - name: Test
         run: |
-          rsync build/install/helma/ antville.dev:/ \
-            --verbose --archive --delete --compress \
-            --filter 'protect /lib/ext' \
-            --filter '+ /launcher.jar' \
-            --filter '+ /lib' \
-            --filter '- /*' \
-
-      - name: Restart Helma
-        run: ssh antville.dev restart
+          echo $SSH_AUTH_SOCK