dockcheck is simple CLI tool to simplify keeping track of and updating your containers. Selective semi/fully auto updates, notifications on new versions and much more.
Another 6 months have passed and a bunch of updates have been made. The most recent ones are multi-threaded/asynchronous checks to greatly increase speed, notifications on new dockcheck release for those who run scheduled unattended checks, osx and bsd compatibility changes, prometheus exporter to push stats to eg. Grafana and more.
I’m happy to see the project still being used and improved by its users as I thought other great tools (dockge, wud, watchtower and others) would replace it.
As it’s been a while I’ll try to list the features:
- Checks all your containers for new updates, without pulling.
- Manually select which containers or choose all.
- Either run it to auto update all, or not update any and just list results.
- Tie it to notify you on new updates.
- Templates: Synology DSM, mSMTP, Apprise, ntfy.sh , Gotify , Pushbullet , Telegram , Matrix, Pushover , Discord.
- Enrich with urls to container release notes.
- Optionally export metrics to Prometheus to show how many images got updates available in a graph.
- Other misc options as:
- Use labels to only update containers with label set.
- Use a N days old option to only update images that have been stable release N days.
- Auto prune dangling images.
- Include stopped containers.
- Exclude specific containers.
I’ve got to thank this community for contributing with donations, ideas, surfacing issues, testing and PRs. It’s a joy!
Great work !
This is a great tool, thanks for the continued support.
Personally, I don’t actually use dockcheck to perform updates, I only use it for its update check functionality, along with a custom plugin which, in cooperation with a python script of mine, serves a REST API that lists all containers on all of my systems with available updates. That then gets pulled into homepage using their custom API function to make something like this: https://imgur.com/a/tAaJ6xf
So at a glance I can see any containers that have updates available, then I can hop into Dockge to actually apply them on my own schedule.
Neat!
Thank you! Oh! That’s pretty cool, do you mind sharing bits of how this is done? Would be nice to incorporate into a notify-template in the future.
Sure, it’s a bit hack-and-slash, but not too bad. Honestly the dockcheck portion is already pretty complete, I’m not sure what all you could add to improve it. The custom plugin I’m using does nothing more than dump the array of container names with available updates to a comma-separated list in a file. In addition to that I also have a wrapper for dockcheck which does two things:
- dockcheck plugins only run when there’s at least one container with available updates, so the wrapper is used to handle cases when there are no available updates.
- Some containers aren’t handled by dockcheck because they use their own management system, two examples are bitwarden and mailcow. The wrapper script can be modified as needed to support handling those as well, but that has to be one-off since there’s no general-purpose way to handle checking for updates on containers that insist on doing things in their own custom way.
Basically there are 5 steps to the setup:
- Enable Prometheus metrics from Docker (this is just needed to get running/stopped counts, if those aren’t needed it can skipped). To do that, add the following to /etc/docker/daemon.json (create it if necessary) and restart Docker:
{ "metrics-addr": "127.0.0.1:9323" }
Once running, you should be able to run
curl http://localhost:9323/metrics
and see a dump of Prometheus metrics- Clone dockcheck, and create a custom plugin for it at dockcheck/notify.sh:
send_notification() { Updates=("$@") UpdToString=$(printf ", %s" "${Updates[@]}") UpdToString=${UpdToString:2} File=updatelist_local.txt echo -n $UpdToString > $File }
- Create a wrapper for dockcheck:
#!/bin/bash cd $(dirname $0) ./dockcheck/dockcheck.sh -mni if [[ -f updatelist_local.txt ]]; then mv updatelist_local.txt updatelist.txt else echo -n "None" > updatelist.txt fi
At this point you should be able to run your script, and at the end you’ll have the file “updatelist.txt” which will either contain a comma-separated list of all containers with available updates, or “None” if there are none. Add this script into cron to run on whatever cadence you want, I use 4 hours.
- The main Python script:
#!/usr/bin/python3 from flask import Flask, jsonify import os import time import requests import json app = Flask(__name__) # Listen addresses for docker metrics dockerurls = ['http://127.0.0.1:9323/metrics'] # Other dockerstats servers staturls = [] # File containing list of pending updates updatefile = '/path/to/updatelist.txt' @app.route('/metrics', methods=['GET']) def get_tasks(): running = 0 stopped = 0 updates = "" for url in dockerurls: response = requests.get(url) if (response.status_code == 200): for line in response.text.split("\n"): if 'engine_daemon_container_states_containers{state="running"}' in line: running += int(line.split()[1]) if 'engine_daemon_container_states_containers{state="paused"}' in line: stopped += int(line.split()[1]) if 'engine_daemon_container_states_containers{state="stopped"}' in line: stopped += int(line.split()[1]) for url in staturls: response = requests.get(url) if (response.status_code == 200): apidata = response.json() running += int(apidata['results']['running']) stopped += int(apidata['results']['stopped']) if (apidata['results']['updates'] != "None"): updates += ", " + apidata['results']['updates'] if (os.path.isfile(updatefile)): st = os.stat(updatefile) age = (time.time() - st.st_mtime) if (age < 86400): f = open(updatefile, "r") temp = f.readline() if (temp != "None"): updates += ", " + temp else: updates += ", Error" else: updates += ", Error" if not updates: updates = "None" else: updates = updates[2:] status = { 'running': running, 'stopped': stopped, 'updates': updates } return jsonify({'results': status}) if __name__ == '__main__': app.run(host='0.0.0.0')
The neat thing about this program is it’s nestable, meaning if you run steps 1-4 independently on all of your Docker servers (assuming you have more than one), then you can pick one of the machines to be the “master” and update the “staturls” variable to point to the other ones, allowing it to collect all of the data from other copies of itself into its own output. If the output of this program will only need to be accessed from localhost, you can change the host variable in app.run to 127.0.0.1 to lock it down. Once this is running, you should be able to run
curl http://localhost:5000/metrics
and see the running and stopped container counts and available updates for the current machine and any other machines you’ve added into “staturls”. You can then turn this program into a service or launch it @reboot in cron or in /etc/rc.local, whatever fits with your management style to start it up on boot.- Finally, the Homepage custom API to pull the data into the dashboard:
widget: type: customapi url: http://localhost:5000/metrics refreshInterval: 2000 display: list mappings: - field: results: running label: Running format: number - field: results: stopped label: Stopped format: number - field: results: updates label: Updates
Curious how this compares to Watchtower.
It’s a different approach. This project started as a proof of concept - just to show that it’s possible to check for updates without pulling the whole image first (which is how Watchtower does it).
Then it evolved to orchestrate granular automatic updates with a bunch of extra functionality - while still adhering to the core goal of keeping it simple and lightweight.
I’m happy with [dockge] (https://github.com/louislam/dockge) for now but thanks! If I ever decide to go full auto update, I’ll check this out.
This looks great. Thanks so much for your work on this and sharing with us.
What in your opinion sets your software apart from the other options you mention?
I have recently setup dockers for plex, immich, nextcloud and paperlessngx but have yet to look at longterm maintenence inc. things like auto updates (I know to avoid on immich).
As someone who prob knows the options inside and out - would you recommend your option to this relative newbie or do you think one of the other options might be a better place to start?
Thank you!
I sadly don’t have too much insights in the other alternatives, I try to not compare too much - maybe I should study them a bit more to understand the wider picture. There’s a few more I forgot to mention; renovate and dependabot.
While I think all those tools are great and have functionality that my project cant fulfill - I strive to keep dockcheck simple and lightweight. Options and functionality have been bolted on bit by bit while still trying to have it as simple as possible in its core functions - so a user could just download the main script
dockcheck.sh
and run it to list updates and optionally update. Everything else is optional, extras.I guess it depends on what you’re looking for. If you’d like a GUI or more in depth setup or reporting - I’d look elsewhere, but if you’d like simplicity and maybe schedule it to notify you when there’s updates available - my project may be the thing.
So my answer would be yes: if you’re running
docker compose
this project is very newbie friendly and easy to get going!Thanks so much for the reply, I’ll give it a download to play with it - I certainly am a big fan of simple!