docker image to install nsinit

Dockerfile

# nsinit installer
#
# VERSION: see `TAG`
FROM ubuntu:14.04
MAINTAINER Joao Paulo Dubas "joao.dubas@gmail.com"

# install deps
RUN apt-get -y -qq --force-yes update \
    && apt-get -y -qq --force-yes install build-essential wget git

# download golang
ENV GOVERSION 1.3
ENV GOFILE go${GOVERSION}.linux-amd64.tar.gz
ENV GOURL http://golang.org/dl/$GOFILE
RUN mkdir -p /opt/src \
    && cd /opt/src \
    && wget ${GOURL} \
    && tar -xzf ${GOFILE}

# install golang
RUN mkdir -p /opt/bin \
    && ln -s /opt/src/go/bin/* /opt/bin/
ENV PATH /opt/bin:$PATH

# configure golang
RUN mkdir -p /opt/go
ENV GOROOT /opt/src/go
ENV GOPATH /opt/go
ENV PATH $GOPATH/bin:$PATH

# install nsinit
RUN go get -d github.com/docker/libcontainer/nsinit/nsinit \
    && go install github.com/docker/libcontainer/nsinit/nsinit \
    && cp ${GOPATH}/bin/nsinit /

# add installer
ADD installer /installer

# configure container
CMD ["/installer"]

installer

#!/bin/sh
# Copied from https://github.com/jpetazzo/nsenter
if mountpoint -q /target; then
        echo "Installing nsinit to /target"
        cp /nsinit /target
else
        echo "/target is not a mountpoint"
        echo "You can either:"
        echo "  - re-run this container with -v /usr/local/bin:/target"
        echo "  - extract nsinit binary (located at /nsinit)"
fi