docker/mkimage-debootstrap.sh

   1 #!/bin/bash
   2 set -e
   3
   4 variant='minbase'
   5 include='iproute,iputils-ping'
   6 arch='amd64' # intentionally undocumented for now
   7 skipDetection=
   8 strictDebootstrap=
   9 justTar=
  10
  11 usage() {
  12         echo >&2
  13
  14         echo >&2 "usage: $0 [options] repo suite [mirror]"
  15
  16         echo >&2
  17         echo >&2 'options: (not recommended)'
  18         echo >&2 "  -p set an http_proxy for debootstrap"
  19         echo >&2 "  -v $variant # change default debootstrap variant"
  20         echo >&2 "  -i $include # change default package includes"
  21         echo >&2 "  -d # strict debootstrap (do not apply any docker-specific tweaks)"
  22         echo >&2 "  -s # skip version detection and tagging (ie, precise also tagged as 12.04)"
  23         echo >&2 "     # note that this will also skip adding universe and/or security/updates to sources.list"
  24         echo >&2 "  -t # just create a tarball, especially for dockerbrew (uses repo as tarball name)"
  25
  26         echo >&2
  27         echo >&2 "   ie: $0 username/debian squeeze"
  28         echo >&2 "       $0 username/debian squeeze http://ftp.uk.debian.org/debian/"
  29
  30         echo >&2
  31         echo >&2 "   ie: $0 username/ubuntu precise"
  32         echo >&2 "       $0 username/ubuntu precise http://mirrors.melbourne.co.uk/ubuntu/"
  33
  34         echo >&2
  35         echo >&2 "   ie: $0 -t precise.tar.bz2 precise"
  36         echo >&2 "       $0 -t wheezy.tgz wheezy"
  37         echo >&2 "       $0 -t wheezy-uk.tar.xz wheezy http://ftp.uk.debian.org/debian/"
  38
  39         echo >&2
  40 }
  41
  42 # these should match the names found at http://www.debian.org/releases/
  43 debianStable=wheezy
  44 debianUnstable=sid
  45 # this should match the name found at http://releases.ubuntu.com/
  46 ubuntuLatestLTS=precise
  47
  48 while getopts v:i:a:p:dst name; do
  49         case "$name" in
  50                 p)
  51                         http_proxy="$OPTARG"
  52                         ;;
  53                 v)
  54                         variant="$OPTARG"
  55                         ;;
  56                 i)
  57                         include="$OPTARG"
  58                         ;;
  59                 a)
  60                         arch="$OPTARG"
  61                         ;;
  62                 d)
  63                         strictDebootstrap=1
  64                         ;;
  65                 s)
  66                         skipDetection=1
  67                         ;;
  68                 t)
  69                         justTar=1
  70                         ;;
  71                 ?)
  72                         usage
  73                         exit 0
  74                         ;;
  75         esac
  76 done
  77 shift $(($OPTIND - 1))
  78
  79 repo="$1"
  80 suite="$2"
  81 mirror="${3:-}" # stick to the default debootstrap mirror if one is not provided
  82
  83 if [ ! "$repo" ] || [ ! "$suite" ]; then
  84         usage
  85         exit 1
  86 fi
  87
  88 # some rudimentary detection for whether we need to "sudo" our docker calls
  89 set +e
  90 docker=`which docker.io`
  91 if [[ "$docker" == "" ]]; then
  92         docker=`which docker`
  93 fi
  94 set -e
  95
  96 if $docker version > /dev/null 2>&1; then
  97         docker="$docker"
  98 elif sudo $docker version > /dev/null 2>&1; then
  99         docker="sudo $docker"
 100 elif command -v $docker > /dev/null 2>&1; then
 101         docker="$docker"
 102 else
 103         echo >&2 "warning: either docker isn't installed, or your current user cannot run it;"
 104         echo >&2 "         this script is not likely to work as expected"
 105         sleep 3
 106         docker='docker' # give us a command-not-found later
 107 fi
 108
 109 # make sure we have an absolute path to our final tarball so we can still reference it properly after we change directory
 110 if [ "$justTar" ]; then
 111         if [ ! -d "$(dirname "$repo")" ]; then
 112                 echo >&2 "error: $(dirname "$repo") does not exist"
 113                 exit 1
 114         fi
 115         repo="$(cd "$(dirname "$repo")" && pwd -P)/$(basename "$repo")"
 116 fi
 117
 118 # will be filled in later, if [ -z "$skipDetection" ]
 119 lsbDist=''
 120
 121 target="${TMPDIR:-/tmp}/docker-rootfs-debootstrap-$suite-$$-$RANDOM"
 122
 123 cd "$(dirname "$(readlink -f "$BASH_SOURCE")")"
 124 returnTo="$(pwd -P)"
 125
 126 set -x
 127
 128 # bootstrap
 129 mkdir -p "$target"
 130 sudo http_proxy=$http_proxy debootstrap --verbose --variant="$variant" --include="$include" --arch="$arch" "$suite" "$target" "$mirror"
 131
 132 cd "$target"
 133
 134 if [ -z "$strictDebootstrap" ]; then
 135         # prevent init scripts from running during install/update
 136         #  policy-rc.d (for most scripts)
 137         echo $'#!/bin/sh\nexit 101' | sudo tee usr/sbin/policy-rc.d > /dev/null
 138         sudo chmod +x usr/sbin/policy-rc.d
 139         #  initctl (for some pesky upstart scripts)
 140         sudo chroot . dpkg-divert --local --rename --add /sbin/initctl
 141         sudo ln -sf /bin/true sbin/initctl
 142         # see https://github.com/dotcloud/docker/issues/446#issuecomment-16953173
 143
 144         # shrink the image, since apt makes us fat (wheezy: ~157.5MB vs ~120MB)
 145         sudo chroot . apt-get clean
 146
 147         # while we're at it, apt is unnecessarily slow inside containers
 148         #  this forces dpkg not to call sync() after package extraction and speeds up install
 149         #    the benefit is huge on spinning disks, and the penalty is nonexistent on SSD or decent server virtualization
 150         echo 'force-unsafe-io' | sudo tee etc/dpkg/dpkg.cfg.d/02apt-speedup > /dev/null
 151         #  we want to effectively run "apt-get clean" after every install to keep images small
 152         echo 'DPkg::Post-Invoke {"/bin/rm -f /var/cache/apt/archives/*.deb || true";};' | sudo tee etc/apt/apt.conf.d/no-cache > /dev/null
 153
 154         # helpful undo lines for each the above tweaks (for lack of a better home to keep track of them):
 155         #  rm /usr/sbin/policy-rc.d
 156         #  rm /sbin/initctl; dpkg-divert --rename --remove /sbin/initctl
 157         #  rm /etc/dpkg/dpkg.cfg.d/02apt-speedup
 158         #  rm /etc/apt/apt.conf.d/no-cache
 159
 160         if [ -z "$skipDetection" ]; then
 161                 # see also rudimentary platform detection in hack/install.sh
 162                 lsbDist=''
 163                 if [ -r etc/lsb-release ]; then
 164                         lsbDist="$(. etc/lsb-release && echo "$DISTRIB_ID")"
 165                 fi
 166                 if [ -z "$lsbDist" ] && [ -r etc/debian_version ]; then
 167                         lsbDist='Debian'
 168                 fi
 169
 170                 case "$lsbDist" in
 171                         Debian)
 172                                 # add the updates and security repositories
 173                                 if [ "$suite" != "$debianUnstable" -a "$suite" != 'unstable' ]; then
 174                                         # ${suite}-updates only applies to non-unstable
 175                                         sudo sed -i "p; s/ $suite main$/ ${suite}-updates main/" etc/apt/sources.list
 176
 177                                         # same for security updates
 178                                         echo "deb http://security.debian.org/ $suite/updates main" | sudo tee -a etc/apt/sources.list > /dev/null
 179                                 fi
 180                                 ;;
 181                         Ubuntu)
 182                                 # add the universe, updates, and security repositories
 183                                 sudo sed -i "
 184                                         s/ $suite main$/ $suite main universe/; p;
 185                                         s/ $suite main/ ${suite}-updates main/; p;
 186                                         s/ $suite-updates main/ ${suite}-security main/
 187                                 " etc/apt/sources.list
 188                                 ;;
 189                 esac
 190         fi
 191 fi
 192
 193 if [ "$justTar" ]; then
 194         # create the tarball file so it has the right permissions (ie, not root)
 195         touch "$repo"
 196
 197         # fill the tarball
 198         sudo tar --numeric-owner -caf "$repo" .
 199 else
 200         # create the image (and tag $repo:$suite)
 201         sudo tar --numeric-owner -c . | $docker import - $repo:$suite
 202
 203         # test the image
 204         $docker run -i -t $repo:$suite echo success
 205
 206         if [ -z "$skipDetection" ]; then
 207                 case "$lsbDist" in
 208                         Debian)
 209                                 if [ "$suite" = "$debianStable" -o "$suite" = 'stable' ] && [ -r etc/debian_version ]; then
 210                                         # tag latest
 211                                         $docker tag $repo:$suite $repo:latest
 212
 213                                         if [ -r etc/debian_version ]; then
 214                                                 # tag the specific debian release version (which is only reasonable to tag on debian stable)
 215                                                 ver=$(cat etc/debian_version)
 216                                                 $docker tag $repo:$suite $repo:$ver
 217                                         fi
 218                                 fi
 219                                 ;;
 220                         Ubuntu)
 221                                 if [ "$suite" = "$ubuntuLatestLTS" ]; then
 222                                         # tag latest
 223                                         $docker tag $repo:$suite $repo:latest
 224                                 fi
 225                                 if [ -r etc/lsb-release ]; then
 226                                         lsbRelease="$(. etc/lsb-release && echo "$DISTRIB_RELEASE")"
 227                                         if [ "$lsbRelease" ]; then
 228                                                 # tag specific Ubuntu version number, if available (12.04, etc.)
 229                                                 $docker tag $repo:$suite $repo:$lsbRelease
 230                                         fi
 231                                 fi
 232                                 ;;
 233                 esac
 234         fi
 235 fi
 236
 237 # cleanup
 238 cd "$returnTo"
 239 sudo rm -rf "$target"