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 docker=''
  90 if docker version > /dev/null 2>&1; then
  91         docker='docker'
  92 elif sudo docker version > /dev/null 2>&1; then
  93         docker='sudo docker'
  94 elif command -v docker > /dev/null 2>&1; then
  95         docker='docker'
  96 else
  97         echo >&2 "warning: either docker isn't installed, or your current user cannot run it;"
  98         echo >&2 "         this script is not likely to work as expected"
  99         sleep 3
 100         docker='docker' # give us a command-not-found later
 101 fi
 102
 103 # make sure we have an absolute path to our final tarball so we can still reference it properly after we change directory
 104 if [ "$justTar" ]; then
 105         if [ ! -d "$(dirname "$repo")" ]; then
 106                 echo >&2 "error: $(dirname "$repo") does not exist"
 107                 exit 1
 108         fi
 109         repo="$(cd "$(dirname "$repo")" && pwd -P)/$(basename "$repo")"
 110 fi
 111
 112 # will be filled in later, if [ -z "$skipDetection" ]
 113 lsbDist=''
 114
 115 target="/tmp/docker-rootfs-debootstrap-$suite-$$-$RANDOM"
 116
 117 cd "$(dirname "$(readlink -f "$BASH_SOURCE")")"
 118 returnTo="$(pwd -P)"
 119
 120 set -x
 121
 122 # bootstrap
 123 mkdir -p "$target"
 124 sudo http_proxy=$http_proxy debootstrap --verbose --variant="$variant" --include="$include" --arch="$arch" "$suite" "$target" "$mirror"
 125
 126 cd "$target"
 127
 128 if [ -z "$strictDebootstrap" ]; then
 129         # prevent init scripts from running during install/update
 130         #  policy-rc.d (for most scripts)
 131         echo $'#!/bin/sh\nexit 101' | sudo tee usr/sbin/policy-rc.d > /dev/null
 132         sudo chmod +x usr/sbin/policy-rc.d
 133         #  initctl (for some pesky upstart scripts)
 134         sudo chroot . dpkg-divert --local --rename --add /sbin/initctl
 135         sudo ln -sf /bin/true sbin/initctl
 136         # see https://github.com/dotcloud/docker/issues/446#issuecomment-16953173
 137
 138         # shrink the image, since apt makes us fat (wheezy: ~157.5MB vs ~120MB)
 139         sudo chroot . apt-get clean
 140
 141         # while we're at it, apt is unnecessarily slow inside containers
 142         #  this forces dpkg not to call sync() after package extraction and speeds up install
 143         #    the benefit is huge on spinning disks, and the penalty is nonexistent on SSD or decent server virtualization
 144         echo 'force-unsafe-io' | sudo tee etc/dpkg/dpkg.cfg.d/02apt-speedup > /dev/null
 145         #  we want to effectively run "apt-get clean" after every install to keep images small
 146         echo 'DPkg::Post-Invoke {"/bin/rm -f /var/cache/apt/archives/*.deb || true";};' | sudo tee etc/apt/apt.conf.d/no-cache > /dev/null
 147
 148         # helpful undo lines for each the above tweaks (for lack of a better home to keep track of them):
 149         #  rm /usr/sbin/policy-rc.d
 150         #  rm /sbin/initctl; dpkg-divert --rename --remove /sbin/initctl
 151         #  rm /etc/dpkg/dpkg.cfg.d/02apt-speedup
 152         #  rm /etc/apt/apt.conf.d/no-cache
 153
 154         if [ -z "$skipDetection" ]; then
 155                 # see also rudimentary platform detection in hack/install.sh
 156                 lsbDist=''
 157                 if [ -r etc/lsb-release ]; then
 158                         lsbDist="$(. etc/lsb-release && echo "$DISTRIB_ID")"
 159                 fi
 160                 if [ -z "$lsbDist" ] && [ -r etc/debian_version ]; then
 161                         lsbDist='Debian'
 162                 fi
 163
 164                 case "$lsbDist" in
 165                         Debian)
 166                                 # add the updates and security repositories
 167                                 if [ "$suite" != "$debianUnstable" -a "$suite" != 'unstable' ]; then
 168                                         # ${suite}-updates only applies to non-unstable
 169                                         sudo sed -i "p; s/ $suite main$/ ${suite}-updates main/" etc/apt/sources.list
 170
 171                                         # same for security updates
 172                                         echo "deb http://security.debian.org/ $suite/updates main" | sudo tee -a etc/apt/sources.list > /dev/null
 173                                 fi
 174                                 ;;
 175                         Ubuntu)
 176                                 # add the universe, updates, and security repositories
 177                                 sudo sed -i "
 178                                         s/ $suite main$/ $suite main universe/; p;
 179                                         s/ $suite main/ ${suite}-updates main/; p;
 180                                         s/ $suite-updates main/ ${suite}-security main/
 181                                 " etc/apt/sources.list
 182                                 ;;
 183                 esac
 184         fi
 185 fi
 186
 187 if [ "$justTar" ]; then
 188         # create the tarball file so it has the right permissions (ie, not root)
 189         touch "$repo"
 190
 191         # fill the tarball
 192         sudo tar --numeric-owner -caf "$repo" .
 193 else
 194         # create the image (and tag $repo:$suite)
 195         sudo tar --numeric-owner -c . | $docker import - $repo:$suite
 196
 197         # test the image
 198         $docker run -i -t $repo:$suite echo success
 199
 200         if [ -z "$skipDetection" ]; then
 201                 case "$lsbDist" in
 202                         Debian)
 203                                 if [ "$suite" = "$debianStable" -o "$suite" = 'stable' ] && [ -r etc/debian_version ]; then
 204                                         # tag latest
 205                                         $docker tag $repo:$suite $repo latest
 206
 207                                         if [ -r etc/debian_version ]; then
 208                                                 # tag the specific debian release version (which is only reasonable to tag on debian stable)
 209                                                 ver=$(cat etc/debian_version)
 210                                                 $docker tag $repo:$suite $repo $ver
 211                                         fi
 212                                 fi
 213                                 ;;
 214                         Ubuntu)
 215                                 if [ "$suite" = "$ubuntuLatestLTS" ]; then
 216                                         # tag latest
 217                                         $docker tag $repo:$suite $repo latest
 218                                 fi
 219                                 if [ -r etc/lsb-release ]; then
 220                                         lsbRelease="$(. etc/lsb-release && echo "$DISTRIB_RELEASE")"
 221                                         if [ "$lsbRelease" ]; then
 222                                                 # tag specific Ubuntu version number, if available (12.04, etc.)
 223                                                 $docker tag $repo:$suite $repo $lsbRelease
 224                                         fi
 225                                 fi
 226                                 ;;
 227                 esac
 228         fi
 229 fi
 230
 231 # cleanup
 232 cd "$returnTo"
 233 sudo rm -rf "$target"