local-docker-registry-sync.sh

#!/bin/bash
# This shell script allows you to maintain a local cache of public images.
#
# Just add your images in CACHE_IMAGES, and it will push the image to the
# registry specified in LOCAL_REGISTRY.
# The / in the origin image name is replaced by a -.
#    google/cadvisor => local_registry:5000/google-cadvisor
#
# If you want to rename the destination image, just specify the destination name
# after a comma. For instance:
#    'google/cadvisor,cadvisor'
#
# You can specify a specific version to sync like:
#    'google/cadvisor:0.5.0'
# Otherwise, it will default to latest.
#
# You can probably use this as a cronjob to sync every hour or so.

COLOR_MSG="\033[1;36m"
COLOR_ERROR="\033[1;31m"
COLOR_WARN="\033[1;93m"
COLOR_RESET="\033[0m"

declare -a CACHE_IMAGES=(
    'clue/h5ai'
    'nickstenning/graphite'
    'google/cadvisor'
    'kubernetes/heapster_influxdb'
    'kubernetes/heapster_grafana'
    'kubernetes/heapster'
    'million12/toolbox'
    'ruby:2.1'
    'ruby:2.2'
    'corfr/calamari-server'
    'corfr/calamari-minion'
    'corfr/coreos-pxe-spoke'
    'corfr/coreos-pxe-hub'
    'corfr/jenkins-swarm-docker-client'
    'corfr/jenkins-swarm-docker-client:1.7.1'
    'corfr/jenkins-swarm-docker-client:1.6.2'
    'corfr/jenkins-job-builder'
    'corfr/git-autoupdate'
    'corfr/yocto-dev'
    'corfr/subgit'
    'corfr/sensu-client'
    'corfr/vmware-tools'
    'ceph/daemon'
    'ceph/config'
    'pataquets/gearmand'
    'mribeiro/xmllint'
    'python:2.7.9'
    'busybox'
    'sstarcher/sensu'
    'sstarcher/uchiwa'
)

REMOTE_REGISTRY=${REMOTE_REGISTRY:-"registry.hub.docker.com"}
REMOTE_REGISTRY_PROTOCOL=${REMOTE_REGISTRY_PROTOCOL:-"https"}

LOCAL_REGISTRY=${LOCAL_REGISTRY:-"registry-legato:5000"}
LOCAL_REGISTRY_PROTOCOL=${LOCAL_REGISTRY_PROTOCOL:-"http"}

function check_ret {
    RETVAL=$?
    if [ $RETVAL -ne 0 ]; then
        echo -e $COLOR_ERROR "Exit Code $RETVAL" $COLOR_RESET
        exit $RETVAL
    fi
}

function get_registry_image_id {
    registry=$1
    http_protocol=$2

    repo=$3
    version=$4

    curl ${http_protocol}://$registry/v1/repositories/$repo/tags/$version > /tmp/registry-img.id 2> /dev/null
    if grep pk /tmp/registry-img.id > /dev/null; then
       jq -r .[0].id /tmp/registry-img.id
    else
       jq -r . /tmp/registry-img.id | cut -c 1-8
    fi

    return 0
}

function sync_image {
    img=$1
    dst=$2

    src=$(echo $img | sed 's/,.*//g')

    if [ -z "$dst" ]; then
        dst=$(echo $img | sed 's/.*,//g')
    fi

    version=$(echo $src | sed 's/.*:\([^:]*\)$/\1/g')
    src_orig=$src

    # Version specified ?
    if [[ "$version" == "$src" ]]; then
        version="latest"
    else
        src=$(echo $src | sed "s/:$version//g")
    fi

    # Destination specified ?
    if [[ "$src_orig" == "$dst" ]]; then
        dst=$(echo $src | sed "s^/^-^g")
    fi

    dst_img="${LOCAL_REGISTRY}/$dst"

    echo -e $COLOR_MSG "Syncing $src -> $dst_img ($version)" $COLOR_RESET


    current_remote_id=$(get_registry_image_id $REMOTE_REGISTRY $REMOTE_REGISTRY_PROTOCOL $src $version)
    echo $current_remote_id
    current_local_id=$(get_registry_image_id $LOCAL_REGISTRY $LOCAL_REGISTRY_PROTOCOL $dst $version)
    echo $current_local_id

    if [[ "$current_remote_id" == "$current_local_id" ]]; then
        return 0
    fi

    docker pull "$src:$version"
    check_ret

    src_hash=$(docker images | grep $version | grep $src | awk '{print $3}' | head -1)
    echo -e $COLOR_MSG "$src -> $src_hash" $COLOR_RESET

    if [ -z "$src_hash" ]; then
        echo "Unable to find hash for $src"
        exit 1
    fi

    docker tag -f $src_hash $dst_img:$version
    check_ret

    docker push $dst_img:$version
    check_ret
}

if [ -z "$1" ]; then
    for img in ${CACHE_IMAGES[@]}; do
        sync_image $img
    done
else
    sync_image $1 $2
fi