Use multi stages builds

[sylr]

Hi,

Current images ship with the building environment it required to build the binaries.

With Docker multi stage builds the result of the build can be copied to a new clean image that does not have the build env with is not required anymore, e.g. :

FROM golang:1.7.3 as builder
WORKDIR /go/src/github.com/alexellis/href-counter/
RUN go get -d -v golang.org/x/net/html  
COPY app.go    .
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o app .

FROM alpine:latest  
RUN apk --no-cache add ca-certificates
WORKDIR /root/
COPY --from=builder /go/src/github.com/alexellis/href-counter/app .
CMD ["./app"]  

With this images will be lighter.

Regards.

[yosifkit]

The alpine-based php images are made for this exact reason; they are small and remove build dependencies in the layer that they are added to save space. No need to have a multi stage build for that.

For more information on why official-images do not use multi stage builds, see docker-library/official-images#3383.