Previous parts: Part I

How to use Docker and Go Modules with private repos?⌗

Since our last talk about using private repositories with Go Modules, I’ve been playing with setting up Docker images for modules-based apps. As you might remember, I wasn’t a fan of Go Mod but that has changed slightly!

The approach below will be based on Bitbucket, but it should work out-of-the-box for any version control system.

FROM golang:1.14.2-alpine AS app

ENV GOPRIVATE=bitbucket.org
ENV GO111MODULE=on

ARG GIT_USERNAME
ARG GIT_PASSWORD

RUN apk add git
RUN apk add openssh
RUN apk add mercurial

RUN git config --global url."https://${GIT_USERNAME}:${GIT_PASSWORD}@bitbucket.org/".insteadOf "https://bitbucket.org/"
WORKDIR /app
COPY . .

RUN go get -d -v
RUN go build -o ./myawesomeapp .

EXPOSE 6161
CMD ["./myawesomeapp"]

But, what has changed?⌗

The major change is the approach to Dockerizing the application - previous one, without modules, was using multi-stage builds to fetch the initial private repos we needed. This one doesn’t have to - but if you want to be extra safe with the username and password, it’s still a very good idea to do so.

Bear in mind, mercurial is currently being phased out until July 1st, 2020 - after that date, you can simplify that docker image.