run

#! /usr/bin/env bash

# Copyright (c) 2015 The Akaros Authors
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version. See LICENSE for details.
#
# Kevin Klues <klueska@gmail.com>

: ${DOCKER_IMAGEBASE:=klueska/akaros-devel}
: ${DOCKER_IMAGETAG:=stable}
: ${DOCKER_HOSTNAME:=akaros-devel}
: ${DOCKER_HOSTSSHPORT:=4405}

# Allow someone to pass the -i flag to force an interactive session
OPT_INTERACTIVE=
while getopts :i opt; do
  case $opt in
    i)
      OPT_INTERACTIVE=true
      shift $((OPTIND-1))
      ;;
  esac
done;

# Other than the -i option, only allow a single tag argument
if [ "$#" -gt 1 ]; then
	echo "Usage: ${0} <tag>"
	echo "    Run the docker image for ${DOCKER_IMAGEBASE}:<tag>"
	echo "    If no <tag> is specified, use '${DOCKER_IMAGETAG}' as default."
	echo "    You can pass -i to force an interactive session, otherwise the image"
	echo "    will be launched with its default command."
	exit 1
fi

# Set up the variables needed to do the actual docker run
# We set USER,GROUP,UID,GID to match the user/group that owns ${currdir}/home
# A user with these credentials will be created inside the docker image upon
# launch and your home directory will be mapped in so you can work from it.
# If no ${currdir}/home directory exists, then we will still start up as our
# user, but no directory will be mapped in for our home directory.
hostname=${DOCKER_HOSTNAME}
dockertag=${DOCKER_IMAGETAG}
if [ "$#" -eq 1 ]; then
	dockertag=$1
fi
dockerimage=${DOCKER_IMAGEBASE}:${dockertag}
currdir=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
if [ -d ${currdir}/home ]; then 
	hosthome=${currdir}/home
	dirmap="-v ${hosthome}:/home/${USER}"
else
	hosthome=${currdir}
fi
envmap="-e USER=$(stat -c "%U" ${hosthome}) \
        -e GROUP=$(stat -c "%G" ${hosthome}) \
        -e UID=$(stat -c "%u" ${hosthome}) \
        -e GID=$(stat -c "%g" ${hosthome})"
portmap="-p ${DOCKER_HOSTSSHPORT}:22"

print_ssh_config() {
local dir=${currdir}
[[ "$dir" =~ ^"${HOME}"(/|$) ]] && dir="~${dir#${HOME}}"
cat << EOF
You can connect with the following settings, which
you should probably add to your .ssh/config file:

	Host akaros-devel
	    Hostname localhost
	    Port 4405
	    IdentityFile ${dir}/docker/home/.ssh/id_rsa
	    IdentitiesOnly yes
	    StrictHostKeyChecking no
	    UserKnownHostsFile /dev/null

With these settings you can simply run the following to connect:
	ssh ${USER}@akaros-devel
EOF
}

# If the docker container is already started, kill the existing one.
running=$(docker ps | grep ${dockerimage})
if [ "${running}" != "" ]; then
	docker rm -f $(echo ${running} | cut -f1 -d " ") > /dev/null
fi

# Start the docker container.
dockerops="--privileged -h ${hostname} ${envmap} ${dirmap} ${portmap}" 
if [ ${OPT_INTERACTIVE} ]; then
	dockerops="${dockerops} -e INTERACTIVE=1 -t -i"
else
	echo "Starting ${dockerimage} in the background"
	dockerops="${dockerops} -d"
	devnull="> /dev/null"
	print_ssh_config
fi
eval docker run ${dockerops} ${dockerimage} ${devnull}