Make app version dynamic: inject git tag version at Docker build time

Author: Raffael Herrmann

.github/workflows/docker-build.yml

@@ -58,4 +58,6 @@ jobs:
         context: .
         push: true
         tags: ${{ steps.meta.outputs.tags }}
-        labels: ${{ steps.meta.outputs.labels }}
+        labels: ${{ steps.meta.outputs.labels }}
+        build-args: |
+          VERSION=${{ steps.get-tag.outputs.tag }}

Dockerfile

@@ -1,9 +1,16 @@
 # Use the official nginx image as the base image
 FROM nginx:alpine
 
+# Accept build argument for version
+ARG VERSION
+ENV VERSION=${VERSION}
+
 # Copy the public directory contents to the nginx html directory
 COPY public/ /usr/share/nginx/html/
 
+# Replace version placeholder
+RUN sed -i "s/__VERSION__/${VERSION}/g" /usr/share/nginx/html/index.html
+
 # Expose port 80
 EXPOSE 80
 

public/index.html

@@ -42,7 +42,7 @@ <h1 class="text-2xl font-bold flex-1 text-center">massCode-Web</h1>
                             <path d="M12 0c-6.626 0-12 5.373-12 12 0 5.302 3.438 9.8 8.207 11.387.599.111.793-.261.793-.577v-2.234c-3.338.726-4.033-1.416-4.033-1.416-.546-1.387-1.333-1.756-1.333-1.756-1.089-.745.083-.729.083-.729 1.205.084 1.839 1.237 1.839 1.237 1.07 1.834 2.807 1.304 3.492.997.107-.775.418-1.305.762-1.604-2.665-.305-5.467-1.334-5.467-5.931 0-1.311.469-2.381 1.236-3.221-.124-.303-.535-1.524.117-3.176 0 0 1.008-.322 3.301 1.23.957-.266 1.983-.399 3.003-.404 1.02.005 2.047.138 3.006.404 2.291-1.552 3.297-1.23 3.297-1.23.653 1.653.242 2.874.118 3.176.77.84 1.235 1.911 1.235 3.221 0 4.609-2.807 5.624-5.479 5.921.43.372.823 1.102.823 2.222v3.293c0 .319.192.694.801.576 4.765-1.589 8.199-6.086 8.199-11.386 0-6.627-5.373-12-12-12z"/>
                         </svg>
                     </a>
-                    <span class="text-gray-400 text-sm">v1.0.0</span>
+                    <span class="text-gray-400 text-sm">__VERSION__</span>
                 </div>
             </footer>
         </aside>