[Feature Request] Docker Updater service widget

[sabbath88]

Description

I'd like a service widget for Docker Updater. It's a lightweight, self-hosted, manual-approval alternative to Watchtower. It polls registries on a schedule, shows which containers have updates and lets you choose when to apply each one,
with rollback and backups. It supports multiple Docker hosts (local, SSH, TCP).

The widget would show container counts at a glance, the same numbers as Docker Updater's dashboard tabs:

Field	Meaning
updates	containers with an update available (default)
uptodate	containers that are up to date (default)
all	all monitored containers (default)
deferred	updates deferred by the user (optional)
unchecked	containers not checked yet (optional)

Proposed config:

widget:
  type: dockerupdater
  url: http://docker-updater.host.or.ip:9292
  username: username # optional, only if auth is enabled in Docker Updater
  password: password # optional

It needs one API call per refresh: GET /api/status, which returns the list of containers with a status field (update, ok, deferred, unknown)
across all configured hosts. Authentication is optional in Docker Updater. When AUTH_USERNAME / AUTH_PASSWORD are set, it uses a session cookie
obtained from POST /login, so the widget logs in on a 401 and retries once, the same way the existing Dockhand widget does. The widget is
read-only.

example:

Other

  Full disclosure: I already have a working implementation, and it was written with the help of AI (Claude Code). I reviewed it and tested it 
  against a real Docker Updater instance with authentication enabled. It includes a docs page and tests, and the existing test suite and lint 
  pass.

  Branch: https://github.com/sabbath88/homepage/tree/feature/docker-updater-widget

  I know the guidelines ask for 20 up-votes before a widget PR, and that young projects may be declined. So I'm opening this first to see if 
  there's interest, and I won't open the PR unless this request gets enough support or a maintainer is fine with it.

  If you'd use this widget, please up-vote 👍

[sabbath88]

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Update: Docker Updater v1.17.0 added an optional read-only API key (API_KEY),
following liquidguru/docker-updater#33.

• It only allows GET /api/status, the single endpoint the widget uses. Everything else still needs the dashboard login, and the key never
  creates a session.
• This means the widget no longer has to store the admin username and password, which could also trigger updates or rollbacks.

The widget on my branch now supports it:

widget:
  type: dockerupdater
  url: http://docker-updater.host.or.ip:9292
  key: apikey # Docker Updater API_KEY (v1.17.0+)

Username and password still work as a fallback for older versions or setups without a key. I tested both against a live instance.

Branch: https://github.com/sabbath88/homepage/tree/feature/docker-updater-widget

As before, this was written with the help of AI (Claude Code) and reviewed and tested by me. I'll only open a PR if this request gets enough support.
👍 if you'd use it!

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