Check updates for Docker images from Docker Hub or private repository, and deploy updated versions to Dokku

README.md

Automatic update of Docker image based applications in Dokku

Check updates for Docker images from Docker Hub or private repository, and deploy updated versions to Dokku.

Requirements

• Bash 4+
• jq
• … Dokku, probably? 🤔

Usage

1. Update the images and privateImages arrays to match your setup
   • The key (blog, matomo, etc.) must correspond to the application name in Dokku
   • For public images, the value is a semicolon-separated string with two values:
     • The first value is Docker Hub path; for official images, replace _ in URL with library (see ghost example); for user images, use both organization name and repository name (see portainer example)
     • The second value is an escaped regex to filter through the retrieved tags; only tags matching the filter will be considered for updates; when in doubt, blame the regex
   • For private images, the value is a semicolon-separated string with five values:
     • The first value is URL for obtaining JWT token
     • The second value is URL for listing all the tags
     • The third value is username for the repository
     • The fourth value is password for the repository
     • The fifth value is regex again
2. Set the script as executable with chmod u+x update-images.bash
3. Run the script with ./update-images.bash

images

declare -A images
declare -A privateImages

images=(
  ["blog"]='https://registry.hub.docker.com/v2/repositories/library/ghost/;^3\\.[[:digit:]]\\+\\.[[:digit:]]\\+-alpine$'
  ["matomo"]='https://registry.hub.docker.com/v2/repositories/library/matomo/;^[[:digit:]]\\+\\.[[:digit:]]\\+\\.[[:digit:]]\\+$'
  ["office"]='https://registry.hub.docker.com/v2/repositories/onlyoffice/documentserver/;^[[:digit:]]\\+\\.[[:digit:]]\\+\\.[[:digit:]]\\+\\.[[:digit:]]\\+$'
  ["portainer"]='https://registry.hub.docker.com/v2/repositories/portainer/portainer/;^[[:digit:]]\\+\\.[[:digit:]]\\+\\.[[:digit:]]\\+$'
)

privateImages=(
  ["files"]='https://docker.seadrive.org/service/token?service=harbor-registry&scope=repository:seafileltd/seafile-pro-mc:pull;https://docker.seadrive.org/v2/seafileltd/seafile-pro-mc/tags/list;<username>;<password>;^7\\.[[:digit:]]\\+\\.[[:digit:]]\\+$'
)

update-images.bash

#!/usr/bin/env bash

set -e

source ./images

updated=false

resolve() {
  image=$1
  currentVersion=$2
  latestVersion=$3

  printf "%30s %s\n" "Currently detected version:" $currentVersion
  printf "%30s %s\n\n" "Latest version found:" $latestVersion

  if [ "$currentVersion" = "$latestVersion" ]; then
    echo "No new version detected. Skipping…"
    echo "====> Finished $image"
    return
  fi

  read -p "Is the above correct? Proceed with update? " -r

  if [[ ! $REPLY =~ ^[Yy]$ ]]; then
    echo "User aborted. Skipping…"
    echo "====> Finished $image"
    return
  fi

  currentImageId=$(dokku tags ${image} | grep dokku | grep latest | awk '{ print $3 }')
  imageName=$(docker image ls | grep -v latest | grep -v dokku | grep ${currentImageId} | awk '{ print $1 }')
  dokkuVersion=$(echo ${latestVersion} | awk -F '-' '{ print $1 }')

  docker image pull ${imageName}:${latestVersion}
  docker image tag ${imageName}:${latestVersion} dokku/${image}:${dokkuVersion}
  dokku tags:deploy ${image} ${dokkuVersion}
  updated=true

  echo "====> Finished $image"
}

for image in "${!privateImages[@]}"; do
  echo "====> Updating $image"

  IN=${privateImages[$image]}
  IFS=";" read -a parameters <<<"$IN"

  tokenUrl="${parameters[0]}"
  tagsUrl="${parameters[1]}"
  username="${parameters[2]}"
  password="${parameters[3]}"
  regex="${parameters[4]}"

  credentials=$(echo -n "${username}:${password}" | base64)
  token=$(curl -L -s -H "Authorization: Basic ${credentials}" ${tokenUrl} | jq -r '."token"')

  currentImageId=$(dokku tags ${image} | grep dokku | grep latest | awk '{ print $3 }')
  currentVersion=$(docker image ls | grep -v latest | grep -v dokku | grep ${currentImageId} | awk '{ print $2 }')
  latestVersion=$(curl -L -s -H "Authorization: Bearer ${token}" ${tagsUrl} | jq -r '."tags"[]' | grep $regex | sort --version-sort | tail -n 1)

  resolve "$image" "$currentVersion" "$latestVersion"
done

for image in "${!images[@]}"; do
  echo "====> Updating $image"

  IN=${images[$image]}
  IFS=";" read -a parameters <<<"$IN"

  registryUrl="${parameters[0]}tags?page_size=1024"
  regex="${parameters[1]}"

  currentImageId=$(dokku tags ${image} | grep dokku | grep latest | awk '{ print $3 }')
  currentVersion=$(docker image ls | grep -v latest | grep -v dokku | grep ${currentImageId}  | awk '{ print $2 }')
  latestVersion=$(curl -L -s ${registryUrl} | jq -r '."results"[]["name"]' | sort --version-sort | grep $regex | tail -n 1)

  resolve "$image" "$currentVersion" "$latestVersion"
done

if [ "$updated" = true ]; then
  read -p "One or more apps were updated. Run \`docker system prune\`? " -n 1 -r

  if [[ ! $REPLY =~ ^[Yy]$ ]]; then
    echo -e "\nWaiting for old containers to stop…"
    sleep 60
    docker system prune
  fi
fi