Script for sending docker images between machines using SSH

docker-send

#!/bin/bash

# MIT License
#
# Copyright (c) 2017 Fabrizio Lungo <opensource@flungo.me>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

# Script for sending docker images between machines using SSH

usage() {
  cat <<EOF
Usage: $0 [-s] image [ssh_opts] [user@]hostname
       $0 -h

Sends a docker image to a remote host using SSH.

  -h        Show this help message
  -s        Use sudo on remote
  image     The name of the docker image to send
  ssh_opts  Additional SSH options for connecting, see \`man ssh\`
  user      The user to connect to the remote host as
  hostname  The hostname of the remote machine
EOF
}

SUDO=""

# Parse the flags for this script
while [ "${1:0:1}" == "-" ]; do
  case "$1" in
    -h)
      usage
      exit 0
      ;;
    -s)
      SUDO="sudo"
      ;;
    *)
      >&2 echo "Unrecognised flag: $1"
      >&2 echo
      >&2 usage
      exit 1
      ;;
  esac
  shift
done

# At least 2 arguments should be left
if [ $# -lt 2 ]; then
  >&2 echo "Not enough arguments"
  >&2 echo
  >&2 usage
  exit 1
fi

# Get the name of the image to send
IMAGE="$1"
shift

# Send the image using bzip compression and showing a progress bar
# See https://stackoverflow.com/a/26226261/2742221
docker save "$IMAGE" | bzip2 | pv | ssh "$@" "bunzip2 | $SUDO docker load"

TODO

• Support other compression formats: no compression, gzip
• Flag to reverse the direction of transfer: -r