Get golang compiler from golang alpine image into another alpine-based image (python in this case).

Dockerfile

# syntax=docker/dockerfile:1

# https://docs.docker.com/engine/reference/builder/#understand-how-arg-and-from-interact
ARG GOLANG_IMAGE=golang:1.18-alpine
ARG PYTHON_IMAGE=python:3.9-alpine

FROM ${GOLANG_IMAGE} AS golang

# installing golang into a python image because it's less hassle
# than the other way around
FROM ${PYTHON_IMAGE}

# live reloader for golang
ARG GOLANG_AIR_VERSION=latest

# golang prep
ENV PATH /usr/local/go/bin:$PATH
ENV GOPATH /go
ENV PATH $GOPATH/bin:$PATH

COPY --from=golang /usr/local/go /usr/local/go

RUN go install github.com/cosmtrek/air@${GOLANG_AIR_VERSION}

WORKDIR /path/to/golang/module

# copy dependency info
COPY ["go.mod", "go.sum", "./"]

# install dependencies
RUN go mod download

# copy source files
COPY . .

CMD [ "air" ]