Tf4fun Watchcow Watchcow

WatchCow Labels — Docker to fnOS App Conversion

WatchCow monitors Docker container events and automatically converts containers with watchcow.enable=true into native fnOS applications. Your job is to add the right labels to a Docker Compose service so WatchCow can pick it up.

The Golden Rule

All label values MUST be quoted strings in YAML — "true", "8080", not bare true or 8080.

Quick Start — Minimal Config

The only required label is watchcow.enable: "true". Everything else has sensible defaults:

labels:
  watchcow.enable: "true"

WatchCow will auto-detect the port (first exposed port), use the container name as display name, and try to find an icon from CDN based on the image name.

Label Reference

App-Level Labels

Entry Labels (Default Entry)

These control how the app appears and opens in fnOS:

Entry Control Permissions

Multi-Entry Labels

For apps with multiple web UIs (e.g. user-facing + admin panel), use named entries with watchcow.<entry>.<field> format. All entry-level fields are supported:

watchcow.<entry>.service_port
watchcow.<entry>.protocol
watchcow.<entry>.path
watchcow.<entry>.redirect
watchcow.<entry>.ui_type
watchcow.<entry>.all_users
watchcow.<entry>.title          # defaults to "<display_name> - <entry>"
watchcow.<entry>.icon
watchcow.<entry>.file_types
watchcow.<entry>.no_display
watchcow.<entry>.control.*

Entry names must NOT conflict with reserved top-level fields (enable, appname, display_name, desc, version, maintainer).

Common Patterns

Pattern 1: Simple Web App

A single-port web service — the most common case.

services:
  memos:
    image: neosmemo/memos:stable
    container_name: memos
    ports:
      - "5230:5230"
    volumes:
      - ./data:/var/opt/memos
    restart: unless-stopped
    network_mode: bridge

    labels:
      watchcow.enable: "true"
      watchcow.display_name: "Memos"
      watchcow.desc: "轻量级笔记与知识管理工具"
      watchcow.service_port: "5230"
      watchcow.icon: "https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/png/memos.png"

Pattern 2: Different Host and Container Ports

When the host port differs from container port, service_port must be the host port.

    ports:
      - "8080:80"        # host 8080 → container 80
    labels:
      watchcow.service_port: "8080"   # use 8080, NOT 80

Pattern 3: External Redirect (Bookmark/Shortcut)

Use watchcow.redirect to create an app that simply opens an external URL. No real web server needed in the container — a lightweight busybox HTTP redirect works:

configs:
  redirect:
    content: |
      #!/bin/sh
      echo "Status: 302 Found"
      echo "Location: https://www.bilibili.com/"
      echo ""

services:
  bilibili:
    image: busybox:uclibc
    container_name: bilibili-redirect
    ports:
      - "3000:3000"
    configs:
      - source: redirect
        target: /www/cgi-bin/index.cgi
        mode: 0755
    command: httpd -f -p 3000 -h /www
    restart: unless-stopped
    stop_signal: SIGKILL
    network_mode: bridge

    labels:
      watchcow.enable: "true"
      watchcow.display_name: "哔哩哔哩"
      watchcow.desc: "一键跳转到 B 站"
      watchcow.service_port: "3000"
      watchcow.path: "/cgi-bin/index.cgi"
      watchcow.icon: "https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/png/bilibili.png"

Pattern 4: Multi-Entry App

An app with a user portal and an admin panel on different ports:

    ports:
      - "8080:8080"
      - "8081:8081"
    labels:
      watchcow.enable: "true"
      watchcow.display_name: "我的应用"

      # User-facing entry
      watchcow.main.service_port: "8080"
      watchcow.main.path: "/"
      watchcow.main.title: "我的应用"

      # Admin entry (admin-only, in desktop window)
      watchcow.admin.service_port: "8081"
      watchcow.admin.path: "/admin"
      watchcow.admin.title: "管理后台"
      watchcow.admin.all_users: "false"
      watchcow.admin.ui_type: "iframe"

Pattern 5: File Handler (Right-Click Menu)

Register an app as a file handler so users can right-click files in fnOS file manager:

    labels:
      watchcow.enable: "true"
      watchcow.display_name: "文本编辑器"

      watchcow.editor.service_port: "8080"
      watchcow.editor.path: "/edit"
      watchcow.editor.title: "用文本编辑器打开"
      watchcow.editor.file_types: "txt,md,json,xml"
      watchcow.editor.no_display: "true"

Pattern 6: Multi-Bookmark with Local Icons

Multiple entries sharing one container, each entry with its own local icon:

    labels:
      watchcow.enable: "true"
      watchcow.display_name: "网站书签"
      watchcow.desc: "常用网站快捷跳转"

      watchcow.bilibili.service_port: "3001"
      watchcow.bilibili.path: "/cgi-bin/index.cgi?bilibili"
      watchcow.bilibili.title: "哔哩哔哩"
      watchcow.bilibili.icon: "file://./icons/bilibili.png"

      watchcow.github.service_port: "3001"
      watchcow.github.path: "/cgi-bin/index.cgi?github"
      watchcow.github.title: "GitHub"
      watchcow.github.icon: "file://icons/github.webp"

file:// relative paths resolve relative to the compose file's directory.

Icon Lookup Priority

1. User-specified watchcow.icon or watchcow.<entry>.icon
2. Local icon library: fnOS File Manager → App Files → icons/ folder
3. CDN: https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/png/<name>.png

Icon naming: default entry uses image name (e.g. nginx:alpine → nginx), named entries use the entry name.

Supported formats: PNG, JPEG, WebP, BMP, ICO — all auto-converted to 256x256 PNG.

Conversion Checklist

When converting a plain Docker Compose file to WatchCow format:

1. Add watchcow.enable: "true" to the main service (the one with a web UI)
2. Set watchcow.display_name and watchcow.desc for a good user experience
3. Set watchcow.service_port to the host port (left side of ports mapping) — only needed if the container exposes multiple ports or you want to be explicit
4. Find an icon: check Dashboard Icons for the app name, or let WatchCow auto-guess
5. Add restart: unless-stopped and network_mode: bridge if not already present
6. For multi-service stacks (e.g. app + database), only label the service with a web UI
7. Quote all label values as strings

Gotchas

• Labels are immutable after container creation. Changing labels requires docker compose down && docker compose up -d (destroy and recreate), not just restart.
• service_port is the host port, not the container port. If ports: "8080:80", use "8080".
• appname must not contain spaces. Use the format watchcow.<name>.
• When using watchcow.redirect, the service_port, protocol, and path labels are ignored — the app opens the redirect URL directly.
• Multi-entry names must avoid reserved words: enable, appname, display_name, desc, version, maintainer cannot be used as entry names.

Source: tf4fun/watchcow — distributed by TomeVault.