Dockerfile

#FROM quay.io/sameersbn/ubuntu:14.04.20151023
#FROM gliderlabs/alpine:3.2
FROM alpine:3.2
MAINTAINER Junior Xu "ayijun@gmail.com"

# http://blog.kontena.io/building-minimal-docker-image-for-rails/
RUN apk --update add ruby ruby-bundler ruby-irb ruby-json ruby-rake \
    ruby-bigdecimal ruby-io-console libstdc++ sqlite-libs openssl && \
    rm /var/cache/apk/*

ENV MAILCATCHER_VERSION=0.6.2

# https://github.com/gliderlabs/docker-alpine/blob/master/docs/usage.md#virtual-packages
RUN apk --update add --virtual build-dependencies build-base ruby-dev openssl-dev sqlite-dev && \
    gem install --no-document mailcatcher -v ${MAILCATCHER_VERSION} && \
    apk del build-dependencies && \
    rm /var/cache/apk/*

# smtp port / webserver port
EXPOSE 1025 1080

CMD ["mailcatcher", "-f", "--ip=0.0.0.0"]