build: github actions - add docker build

.github/workflows/release.yml

@@ -47,3 +47,39 @@ jobs:
       with:
         files: |
           .tarballs/*
+  docker:
+    name: Push Docker image to Docker Hub
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Set up Go 1.x
+        uses: actions/setup-go@v3
+        with:
+          go-version: ^1.18
+
+      - name: Check out the repo
+        uses: actions/checkout@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: burningalchemist/sql_exporter
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v3
+        with:
+          context: .
+          push: false
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          provenance: false