App Connections

App connections

wranglarr wires the stack's apps to each other, based on which ones are enabled, so a fresh stack works without clicking through every arr's settings. It runs once at startup and again whenever you press Connect apps on the System page (src/connect.rs).

What gets wired

App configured	Gets	Where it ends up	Entry
every arr (Radarr, Sonarr, Lidarr, Readarr, Whisparr)	every download client (qBittorrent, SABnzbd, NZBGet)	Settings → Download Clients	named qBittorrent / SABnzbd / NZBGet, enabled, priority 1, category = the arr's name
Bazarr	Sonarr and Radarr (one of each)	Settings → Sonarr / Radarr	use_sonarr / use_radarr on, host, port, base URL, SSL, API key
Prowlarr	every arr	Settings → Apps	an application named Radarr, Sonarr, … with sync level Full Sync, so Prowlarr pushes its indexers to the arr
Prowlarr	every download client	Settings → Download Clients	the same entries, category prowlarr: for grabbing a release from Prowlarr's own search page. No arr imports those; they stay in /data/torrents/prowlarr or /data/usenet/complete/prowlarr
Seerr	every Radarr and Sonarr	Settings → Services	named after the arr; its first quality profile and root folder (your later picks in Seerr are kept); 4k in the name makes it Seerr's 4K server. Only after Seerr's own first-run setup (Connections)

Bazarr and Seerr only know Sonarr and Radarr.

Media servers (Plex, Jellyfin, Emby, Kodi) aren't part of the stack, so they aren't wired automatically: add them on the Connections page, which puts them in the arrs you pick (Connections). The same goes for notifications (Notifications).

An app whose name in wranglarr.toml differs from its kind (a second Radarr called radarr4k, say) gets entries named after it instead.

The credentials come from wranglarr's own config: SABnzbd's API key from sabnzbd.ini, qBittorrent's login from QBITTORRENT_USER / QBITTORRENT_PASSWORD, NZBGet's from NZBGET_USER / NZBGET_PASS, and each arr's API key from its config.xml.

Categories and folders

Each arr's download client entry uses the arr's own name as category (radarr, sonarr, lidarr), so finished downloads land in a folder per arr:

Client	Category folder
qBittorrent	/data/torrents/<arr> (automatic torrent management, set up by init.sh)
SABnzbd	/data/usenet/complete/<arr>
NZBGet	/data/usenet/complete/<arr>

The paths are under the shared /data mount that the arrs see at the same path, so imports can hardlink and no remote path mapping is needed. See Setup for how init.sh sets the clients' save paths.

Before wiring anything, a run:

1. Creates the category folders inside each client's container: mkdir -p <download folder>/<arr> through the Docker socket, as the container's PUID:PGID. The download folder is the one the client reports (qBittorrent's save path, SABnzbd's complete_dir, NZBGet's DestDir). Without the socket, the run log says which folders to create by hand. The arrs warn about a client folder they can't see until the first download creates it, which is why this step exists.
2. Creates the categories in SABnzbd and NZBGet, because the arrs refuse a category the client doesn't have. SABnzbd gets a category per arr (folder = its name, under complete_dir); NZBGet gets Category<N>.Name = <arr> with an empty DestDir (= <DestDir>/<arr>) and is reloaded. qBittorrent needs nothing here: the arr creates the category in it.
3. Wires each link (below).

If mkdir fails, the run log says the download folder isn't writable by PUID:PGID. Downloads would fail too, so fix the folder's ownership (see Troubleshooting).

Addressing

Entries point at the compose service names (qbittorrent:8090, sabnzbd:8080, radarr:7878, …), taken from each app's url in wranglarr.toml.

Apps that share one network namespace reach each other on localhost instead. This is the case for the apps in the shared VPN tunnel (compose.vpn.yaml), which run inside the vpn container's network; an app outside the tunnel still uses the service name (qbittorrent:8090, which is an alias of vpn). wranglarr detects it through the Docker socket: two containers whose NetworkMode points at the same container share a namespace. Without the socket it goes by WRANGLARR_VPN_APPS, the list of apps in the tunnel that the compose files set. With per-app tunnels (compose.vpn-per-app.yaml) each app has its own namespace, so service names are used.

For a Prowlarr application both directions are set: the arr's URL as Prowlarr reaches it, and the Prowlarr URL as the arr reaches it.

Modes

Mode	When	What it does
new	at startup, with [connect] auto = true	only links never handled before; an app that already has a matching entry is left alone ("kept"). Nothing is overwritten.
all	Connect apps button, or a row's connect button	creates missing entries and updates existing ones: host, port, SSL, URL base, credentials and category are set, the entry is enabled, the rest of its settings are kept

An existing entry is one with the same implementation and either the same name or the same host.

Links that were created, updated or kept are recorded in the state db (kv connect:done). The startup run skips them from then on, so a link you remove by hand in an arr is not put back. A link that failed is not recorded and is tried again on the next start. Newly enabled apps get wired on the next start too.

At startup wranglarr waits in the background (up to 15 minutes) until every app involved answers, then runs new for the links whose two apps are up. If none answer it logs a warning and leaves it to the button.

Each entry is tested first

For download clients and Prowlarr applications, the app being configured tests the entry (its downloadclient/test, Prowlarr's applications/test) before wranglarr saves it. A client with wrong credentials, or one the arr can't reach, is therefore not saved; it shows as failed in the run log with the app's own message. Fix the cause (for example QBITTORRENT_PASSWORD in .env, then docker compose up -d wranglarr) and press Connect apps. Seerr tests each Radarr and Sonarr the same way. Bazarr's settings are saved without a test.

Configuration

[connect]
auto = true      # at startup, connect what was never connected before

auto = false turns the startup run off; the button and the API still work.

System page

The App connections panel opens on a map: every app is a box, and every link an arrow from the app that holds the setting to the app it reaches. The columns follow the links: Prowlarr, Bazarr and Seerr on the left, the arrs in the middle, the download clients on the right.

• One arrow head: one app calls the other (an arr sends what it grabs to a download client; Bazarr and Seerr read from Sonarr and Radarr).
• Heads at both ends, in blue: the two reach each other. Prowlarr puts its indexers into the arr, and the arr searches through Prowlarr.
• Colour: green is connected, orange differs or waiting, grey dashed not connected, red an error. An app with a link that isn't connected gets a dot in its corner.

Hover over an app to pick out its links. Click an app or a line to list those links under the map, with a connect button on any that aren't connected.

List (top right) shows the same links as a table. The browser remembers the view you picked.

Column
App	the app being configured
Gets	the app it is pointed at, and what it is (download client, sonarr/radarr, application)
At	the host:port it should use (localhost:… under the shared VPN)
State	connected; not connected; differs (points at another host/port, is disabled, or Bazarr has another API key); waiting (Seerr's first-run setup isn't done: wranglarr retries every 5 minutes and connects it by itself); or an error reading the app

Rows that aren't connected have a connect button (mode all, that link only). Connect apps below the table runs every link in mode all.

Runs are logged like backups (Activity, suite system), one line per folder, category and link.

API

GET    /api/connect                                  links with state, target, detail; "auto"; "missing" count
POST   /api/connect                                  {"mode":"all"|"new","links":["qbittorrent>radarr"]} -> {"run": id}

A link key is <app pointed at>><app configured>: qbittorrent>radarr, sonarr>bazarr, radarr>prowlarr. An empty or missing links means every link; mode defaults to all. Unknown link: 404; bad mode: 400; another system run (an update, an indexer sync) in progress: 409.

What it does not do

• Root folders. Add /data/media/movies, /data/media/tv, /data/media/music in each arr yourself.
• Indexers. Add them in Prowlarr (which the arrs are registered in), or on the Indexers page.
• Remove anything. Entries are only created or updated; removing an app from COMPOSE_PROFILES leaves its entries in the others.
• Quality profiles, notifications, other settings. Shared Settings covers download clients, indexers and notifications defined in wranglarr.toml.