FEAT: Release workflow for docker image

.github/workflows/release.yaml

@@ -4,6 +4,8 @@ on:
   push:
     tags:
       - 'v*'
+    branches:
+      - 'main'
 
 jobs:
   release:
@@ -23,6 +25,7 @@ jobs:
         CGO_ENABLED=0 GOOS=linux go build -o caterpillar ./cmd/caterpillar/caterpillar.go
 
     - name: Create Release
+      if: startsWith(github.ref, 'refs/tags/')
       uses: softprops/action-gh-release@v2
       with:
         files: caterpillar
@@ -31,3 +34,31 @@ jobs:
         prerelease: false
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+    - name: Login to Docker Hub
+      uses: docker/login-action@v3
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+    - name: Extract metadata for Docker
+      id: tagger
+      uses: docker/metadata-action@v5
+      with:
+        images: patternoss/caterpillar
+        tags: |
+          type=semver,pattern={{major}}.{{minor}}.{{patch}}
+          type=raw,value=latest,enable=${{ startsWith(github.ref, 'refs/tags/') }}
+          type=raw,value=main,enable=${{ github.ref == 'refs/heads/main' }}
+
+    - name: Build and push Docker image
+      uses: docker/build-push-action@v5
+      with:
+        context: .
+        file: ./build/Dockerfile
+        push: true
+        tags: ${{ steps.tagger.outputs.tags }}
+        platforms: linux/amd64,linux/arm64

build/Dockerfile

@@ -0,0 +1,13 @@
+FROM golang:1.24.7-alpine AS builder
+
+WORKDIR /go/src/github.com/patterninc/caterpillar
+
+COPY . .
+
+# build executable
+RUN go build -o caterpillar ./cmd/caterpillar/caterpillar.go
+RUN chmod 755 caterpillar
+
+FROM alpine:3.20
+RUN mkdir -p /output
+COPY --from=builder /go/src/github.com/patterninc/caterpillar/caterpillar .