Implement multi-arch Docker builds (amd64, arm64)

Co-authored-by: xDarksome <22872975+xDarksome@users.noreply.github.com>

Author: Copilot

.github/workflows/docker-publish.yml

@@ -28,14 +28,11 @@ jobs:
         with:
           submodules: recursive
 
-      - name: Set up Go
-        uses: actions/setup-go@v4
-        with:
-          go-version-file: go.mod
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
 
-      - name: Build binary
-        run: |
-          CGO_ENABLED=0 go build -ldflags "-s -w" -trimpath -o prom2parquet ./cmd/.
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
 
       - name: Log in to Container Registry
         if: github.event_name != 'pull_request'
@@ -63,6 +60,7 @@ jobs:
         with:
           context: .
           file: ./images/Dockerfile.prom2parquet
+          platforms: linux/amd64,linux/arm64
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}

images/Dockerfile.prom2parquet

@@ -1,10 +1,22 @@
-FROM golang:1.24-alpine
+FROM golang:1.24-alpine AS builder
 
-RUN wget -O /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v1.2.5/dumb-init_1.2.5_x86_64
-RUN chmod +x /usr/local/bin/dumb-init
+WORKDIR /build
+COPY . .
+RUN CGO_ENABLED=0 go build -ldflags "-s -w" -trimpath -o prom2parquet ./cmd/.
 
-RUN go install github.com/go-delve/delve/cmd/dlv@latest
+FROM alpine:latest
 
-COPY prom2parquet /prom2parquet
+ARG TARGETARCH
+RUN apk add --no-cache wget && \
+    case ${TARGETARCH} in \
+        "amd64")  DUMB_INIT_ARCH=x86_64  ;; \
+        "arm64")  DUMB_INIT_ARCH=aarch64  ;; \
+        *)        echo "Unsupported architecture: ${TARGETARCH}" && exit 1 ;; \
+    esac && \
+    wget -O /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v1.2.5/dumb-init_1.2.5_${DUMB_INIT_ARCH} && \
+    chmod +x /usr/local/bin/dumb-init && \
+    apk del wget
+
+COPY --from=builder /build/prom2parquet /prom2parquet
 
 ENTRYPOINT ["/usr/local/bin/dumb-init", "--"]