support build multi-arch image (#175)

Signed-off-by: Ping Yu <yuping@pingcap.com>

Dockerfile

@@ -1,5 +1,5 @@
 # Build the go-tpc binary
-FROM golang:1.18 as builder
+FROM golang:1.21 as builder
 
 WORKDIR /workspace
 COPY go.mod go.mod
@@ -12,9 +12,10 @@ RUN go mod download
 COPY . .
 
 # Build
-RUN GOOS=linux GOARCH=amd64 make build
+ARG TARGETOS TARGETARCH
+RUN GOOS=$TARGETOS GOARCH=$TARGETARCH make build
 
-FROM pingcap/alpine-glibc:3.10
+FROM alpine
 
 RUN apk add --no-cache \
   dumb-init \

Makefile

@@ -13,6 +13,7 @@ GOBUILD=$(GO) build -ldflags '$(LDFLAGS)'
 
 # Image URL to use all building/pushing image targets
 IMG ?= go-tpc:latest
+PLATFORM ?= linux/amd64,linux/arm64
 
 all: format test build
 
@@ -42,3 +43,8 @@ docker-build: test
 
 docker-push: docker-build
 	docker push ${IMG}
+
+# Create multiarch driver if not exists:
+#   docker buildx create --name multiarch --driver docker-container --use
+docker-multiarch: test
+	docker buildx build --platform ${PLATFORM} . -t ${IMG} --push