ci: Improve docker build performance

Author: g3force

.circleci/config.yml

@@ -70,7 +70,7 @@ jobs:
             --driver docker-container \
             --bootstrap --use
           for cmd in << pipeline.parameters.cmds >>; do
-            docker buildx build --platform linux/amd64,linux/arm64 --build-arg cmd=${cmd} -t robocupssl/${cmd}:latest .
+            docker buildx build --platform linux/amd64,linux/arm64 --build-arg BINARY_NAME=${cmd} -t robocupssl/${cmd}:latest .
           done
 
   publish_docker:
@@ -91,7 +91,7 @@ jobs:
           TAG=${TAG:-latest}
           for cmd in << pipeline.parameters.cmds >>; do
             docker login -u "${DOCKER_HUB_USERNAME}" -p "${DOCKER_HUB_PASSWORD}"
-            docker buildx build --platform linux/amd64,linux/arm64 --build-arg cmd=${cmd} -t robocupssl/${cmd}:${TAG} --push .
+            docker buildx build --platform linux/amd64,linux/arm64 --build-arg BINARY_NAME=${cmd} -t robocupssl/${cmd}:${TAG} --push .
           done
 
 workflows:

Dockerfile

@@ -1,13 +1,18 @@
-FROM golang:1.25-alpine@sha256:98e6cffc31ccc44c7c15d83df1d69891efee8115a5bb7ede2bf30a38af3e3c92 AS build_go
-ARG cmd
+FROM --platform=$BUILDPLATFORM golang:1.25-alpine@sha256:98e6cffc31ccc44c7c15d83df1d69891efee8115a5bb7ede2bf30a38af3e3c92 AS build_go
+ARG TARGETOS
+ARG TARGETARCH
+ARG BINARY_NAME
 WORKDIR /work
 COPY . .
-RUN go install ./cmd/${cmd}
+RUN --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    CGO_ENABLED=0 GOOS=$TARGETOS GOARCH=$TARGETARCH \
+    go build -trimpath -ldflags="-w -s" -o /go/bin/${BINARY_NAME} ./cmd/${BINARY_NAME}
 
 # Start fresh from a smaller image
 FROM alpine:3@sha256:25109184c71bdad752c8312a8623239686a9a2071e8825f20acb8f2198c3f659
-ARG cmd
-COPY --from=build_go /go/bin/${cmd} /app
+ARG BINARY_NAME
+COPY --from=build_go /go/bin/${BINARY_NAME} /app
 WORKDIR /data
 RUN chown 1000: /data
 USER 1000

Makefile

@@ -7,7 +7,7 @@ all: install docker
 docker: $(DOCKER_TARGETS)
 
 $(DOCKER_TARGETS): docker-%:
-	docker build --build-arg cmd=$* -t $*:latest .
+	docker build --build-arg BINARY_NAME=$* -t $*:latest .
 
 test:
 	go test ./...