Go multiplatform docker builds

Earthfile

VERSION 0.8
PROJECT jahands/docker

# Local targets:
tidy:
	LOCALLY
	RUN go mod tidy

build-local:
	LOCALLY
	RUN go build -o dist/mycli

# Normal targets:
setup-project:
	FROM golang:1.22
	WORKDIR /work
	COPY go.mod go.sum .
	RUN go mod download
	COPY --dir commands lib .
	COPY .earthlyignore main.go .

build:
	FROM +setup-project
	ARG --required GOOS
	ARG --required GOARCH
	CACHE $(go env GOCACHE)
	RUN GOOS=$GOOS GOARCH=$GOARCH go build -o dist/$GOOS/$GOARCH/mycli
	SAVE ARTIFACT dist

build-docker:
	ARG --required DOCKER_TAG
	ARG --required PLATFORM
	ARG --required GOOS
	ARG --required GOARCH
	BUILD +build --GOOS=$GOOS --GOARCH=$GOARCH

	FROM --platform=$PLATFORM debian:12-slim
	WORKDIR /work
	COPY --chmod=700 +build/dist/$GOOS/$GOARCH/mycli .
	ENTRYPOINT ["./mycli"]

	SAVE IMAGE --push github.com/jahands/mycli:$DOCKER_TAG
	IF [ "$DOCKER_TAG" = "main" ]
		SAVE IMAGE --push github.com/jahands/mycli:latest
	END

docker:
	ARG --required DOCKER_TAG
	BUILD +build-docker --PLATFORM=linux/amd64 --GOOS=linux --GOARCH=amd64 --DOCKER_TAG=$DOCKER_TAG
	BUILD +build-docker --PLATFORM=linux/arm/v7 --GOOS=linux --GOARCH=arm --DOCKER_TAG=$DOCKER_TAG