chore(relayer): Dockerfile + github action on merge to main (#316)

.github/workflows/docker.yml

@@ -0,0 +1,50 @@
+name: "Push docker image to GCR"
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - "packages/relayer/**"
+
+jobs:
+  push-docker-image:
+    name: Build and push docker image
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Login to GCR
+        uses: docker/login-action@v2
+        with:
+          registry: gcr.io
+          username: _json_key
+          password: ${{ secrets.GCR_JSON_KEY }}
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: |
+            gcr.io/evmchain/relayer
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=ref,event=tag
+            type=sha
+
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64
+          push: true
+          context: packages/relayer
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

packages/relayer/Dockerfile

@@ -0,0 +1,19 @@
+FROM golang:1.19.3 as builder
+
+RUN apt install git curl
+
+RUN git clone --depth 1 https://github.com/taikoxyz/taiko-mono /taiko-mono
+
+WORKDIR /taiko-mono/packages/relayer
+
+RUN go mod download
+
+RUN CGO_ENABLED=0 GOOS=linux go build -o ./bin/relayer cmd/main.go
+
+FROM alpine:latest
+
+RUN apk add --no-cache ca-certificates
+
+COPY --from=builder /taiko-mono/packages/relayer/bin/relayer /usr/local/bin/
+
+ENTRYPOINT ["relayer"]