Build docker image (#3)

.github/workflows/go.yml

@@ -15,5 +15,42 @@ jobs:
         run: test -z $(gofmt -l .) || (gofmt -d . && exit 1)
       - uses: actions/upload-artifact@v4
         with:
+          name: binary
           path: mdns2mqtt
           if-no-files-found: error
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build and load
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          outputs: type=docker,dest=/tmp/image.tar
+          tags: invlid/mdns2mqtt:latest
+      - uses: actions/upload-artifact@v4
+        with:
+          name: docker-image
+          path: /tmp/image.tar
+          if-no-files-found: error
+  publish:
+    needs: build
+    if: github.ref == 'refs/heads/master'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: docker-image
+          path: /tmp
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USER }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Load image
+        run: |
+          docker load --input /tmp/image.tar
+      - name: Push image
+        run: |
+          docker push invlid/mdns2mqtt:latest

Dockerfile

@@ -0,0 +1,4 @@
+FROM scratch
+
+COPY mdns2mqtt /
+CMD ["/mdns2mqtt"]