[Haskell-cafe] Dockerfile for Yesod

[Jonathan Paugh]

Greetings, all

I'm brand new to Docker, and struggled to find resources specific to
Yesod. So, once I managed to piece together a Dockerfile, I decided to
share it. Hope it helps someone.

The Dockerfile is pasted at the bottom. It can be used by dropping it in
your Yesod application directory, and replacing "app" with the name of
your app.

If you're new to Docker like I was, cd to your Yesod app dir, and run

    $ docker build --tag app-image .
    $ docker run -d -p 3000:3000 app-image

to get started. Your web app should now be available at
http://localhost:3000

NB: The approot setting can make a profound and confusing difference if
it is mis-configured. I recommend temporarily setting approot to "" so
that it will use absolute (site-relative) urls instead of fully
specified ones.

Happy Holidays,
Jon

Dockerfile
-----------

FROM    haskell:7.8
RUN     cabal update

RUN     apt-get update && apt-get install -y libpq5 libpq-dev

ADD     ./app.cabal /opt/app/app.cabal
WORKDIR /opt/app
RUN     cabal sandbox init
RUN     cabal install --only-dependencies --max-backjumps=-1
--reorder-goals -j

ADD     . /opt/app
RUN     cabal build

RUN     dist/build/db-import/db-import

ENV PATH /opt/app/.cabal-sandbox/bin:$PATH
EXPOSE 3000
CMD ["/opt/app/dist/build/app/app", "production", "-p", "3000"]