# Build stage 
FROM golang:1.21.4-alpine AS builder

WORKDIR /app

COPY go.mod ./

# download Go modules and dependencies
RUN go mod download

# copy all the Go files ending with .go extension
COPY *.go ./

RUN go build -o golang-http-header

# Final stage
FROM scratch

COPY --from=builder /app/golang-http-header /

# network port at runtime
EXPOSE 8000

CMD ["/golang-http-header"]