# CLAUDE.md — ubuntu-post-install contributor guide Context for adding or modifying services. Read this before touching any service file so the result matches what's already here. ## How the system works `setup.sh` sources `lib/common.sh` then globs every `services/*.sh` file. Each service file self-registers and defines its install function. Nothing in `setup.sh` needs to change when you add a service — just add the file. The wizard groups services by category (from `register_service`), shows a checklist per group, and calls `install_()` for each selected item. `--list`, `--dry-run`, and `--unattended` all work automatically. ## Adding a service — the three-step rule 1. Create `services/.sh` (kebab-case filename) 2. Call `register_service` at the top of the file 3. Define `install_()` — keep hyphens **literal** in the function name (`install_pstn-trunk`, not `install_pstn_trunk`). `setup.sh`'s dispatcher calls `install_${name}` with no hyphen→underscore conversion, so the function name must match the service name exactly. Confirmed live: a mismatched underscore here produces `Service 'x' has no install_x` at runtime, not a load-time error. That's it. The menu picks it up on the next run. Also update the **Services table in `README.md`** — add the service name to the appropriate group row so the README stays current. ## Retiring a service name (merging two services) Deleting `services/.sh` removes it from the menu, but `sudo ./setup.sh ` then fails outright for anyone with that name in their notes, docs, or shell history. Add the old name to `SERVICE_ALIAS` in `setup.sh` instead — `run_service` resolves it to the surviving service, says so once, and runs that. The alias never gets its own menu entry, which is the whole point. `services/asterisk-digital-ocean.sh` was merged into `services/asterisk.sh` this way: one installer that detects a DigitalOcean droplet (metadata service, with a y/n either way) and applies the droplet-only extras — swapfile, public-FQDN-only flow, hand-built Caddy site block, remote Authelia, Cloud Firewall — behind that one answer. Two lessons worth reusing: - **Don't rename a live install's directory or containers.** New installs land in `~/docker/asterisk` with `easy-asterisk`; a pre-merge droplet keeps `~/docker/asterisk-digital-ocean` and `easy-asterisk-do`, because its Caddyfile block, UFW rules, Cloud Firewall, CrowdSec acquisition and PSTN trunk all name those exact paths. `_asterisk_resolve_layout()` picks whichever exists, and every sibling service probes both. - **Check whether a "flavor-specific" behavior was actually flavor-specific.** The Asterisk security-logging patch and the `logs/full` logrotate config were droplet-only purely because that's where they got written first — the Security Dashboard's Security Log and CrowdSec's Asterisk acquisition were silently empty on every home/LAN install as a result. Both now apply everywhere. The pre-merge installer is parked at `attic/asterisk-digital-ocean.sh` as a rollback path until the unified one is confirmed on real hardware. `attic/` is outside `setup.sh`'s `services/*.sh` glob, so nothing there registers or runs on its own — see `attic/README.md`, including why it's a way to get the old script back rather than an undo button. Delete it once the merge is proven; a second copy of the same logic is what the merge existed to remove, and fixes are deliberately not backported into it. ## Minimal Docker service template ```bash #!/bin/bash # services/my-tool.sh — One-line description. # Part of the modular post-install system (sourced by setup.sh). register_service my-tool utilities "What it does (My Tool)" 8080 install_my_tool() { require_docker || return 1 local DIR="$DOCKER_DIR/my-tool" if [ "$DRY_RUN" = true ]; then echo "[DRY-RUN] Would create $DIR with docker-compose.yml" return 0 fi mkdir -p "$DIR" ensure_docker_dir_ownership "$DIR" cd "$DIR" || return 1 cat > docker-compose.yml << 'EOF' name: my-tool services: my-tool: image: vendor/my-tool:latest container_name: my-tool restart: unless-stopped ports: - "8080:8080" volumes: - ./data:/data EOF configure_caddy_for_service "My Tool" "8080" "my-tool" write_readme "$DIR" << 'MD' # My Tool Brief description. ## Manage ```bash docker compose up -d docker compose down docker compose logs -f docker compose pull && docker compose up -d ``` MD local START="" prompt_yn "Start My Tool now? (y/n):" "y" START if [ "$START" = "y" ] || [ "$START" = "Y" ]; then docker compose up -d \ && log_success "My Tool started" \ || log_warning "Start failed — check: docker compose logs" fi } ``` ## register_service signature ```bash register_service "" [port] ``` - `name` — kebab-case, matches the filename and the `install_` function - `group` — one of the categories below; determines which menu it appears in - `description` — shown in `--list` and the menu checklist - `port` — optional; informational only (not used by the framework) ## Available globals | Variable | Value | |----------|-------| | `DOCKER_DIR` | `~/docker` — parent for all Docker service directories | | `ACTUAL_USER` | The non-root user that invoked sudo | | `ACTUAL_HOME` | Home directory of `ACTUAL_USER` | | `SITE_TZ` | Timezone from site config, e.g. `America/New_York` | | `SITE_DOMAIN` | Base domain from site config, e.g. `example.com` | | `SITE_CADDY_NET` | Docker network name for Caddy (default: `caddy_net`) | | `DRY_RUN` | `true`/`false` — set by `--dry-run` flag | | `UNATTENDED` | `true`/`false` — set by `--unattended` flag | ## Available helpers (lib/common.sh) ### Logging ```bash log_info "message" # blue [INFO] log_success "message" # green [OK] log_warning "message" # yellow [WARN] log_error "message" # red [ERROR] ``` ### Prompts — honor `UNATTENDED` automatically ```bash prompt_yn "Question? (y/n):" "default_y_or_n" VARNAME prompt_text "Question? [default]:" "default" VARNAME prompt_reinstall_mode VARNAME # sets VARNAME to: update | fresh | cancel ``` When `UNATTENDED=true` all three skip the prompt; `prompt_yn`/`prompt_text` use their given default, `prompt_reinstall_mode` always resolves to `cancel`. See **Update vs. fresh reinstall on rerun** below for how to use the latter. ### Pre-flight ```bash require_root # exits with an error if not running as root require_docker # installs Docker CE + Compose plugin if missing, then returns ``` ### Execution and ownership ```bash run_cmd COMMAND [args...] # no-ops in DRY_RUN, executes otherwise ensure_docker_dir_ownership DIR... # chown -R ACTUAL_USER:ACTUAL_USER (skips in DRY_RUN) generate_password [length] # alphanumeric random string, default 32 chars pip_user_install PACKAGE... # pip3 --user with --break-system-packages on 24.04+ ``` ### Caddy reverse proxy ```bash configure_caddy_for_service "Display Name" "PORT" "default-subdomain" ["extra-block"] ``` Prompts the user for a domain, appends a site block to the Caddyfile, and reloads Caddy. No-ops silently if Caddy isn't installed. The fourth argument is an optional string inserted verbatim inside the Caddy site block (use it for `import authelia` or custom matchers). The function places that block **before** `reverse_proxy` in the generated site block — don't reorder this. `forward_auth` (what `import authelia` expands to) is the same directive family as `reverse_proxy` internally, and Caddy doesn't reorder repeats of the same directive within a block; it runs them in the order they're written. `reverse_proxy` written first would handle and terminate every request immediately, making an auth check written after it dead code that never runs — full bypass regardless of what the auth server's own access-control rules say. Confirmed live: this was the actual cause of a "Caddy proxies fine but Authelia never prompts for login" bug, on a site block that otherwise looked completely correct. If a service builds its own site block instead of using this helper (e.g. `services/asterisk.sh` does in droplet mode, deliberately — see `_asterisk_configure_caddy_public`'s comment for why), put its auth block first there too. **`forward_auth` to a remote Authelia over a scheme-qualified URL needs explicit `header_up` pins.** A bare `forward_auth authelia:9091` (Authelia on the same Docker network, one hop) is fine relying on Caddy's default `X-Forwarded-*` headers. But `forward_auth https://auth.example.com { ... }` (Authelia on a *different* machine, reached over its own public domain+TLS — see `services/asterisk.sh`'s droplet-mode remote-Authelia prompt) is a second Caddy hop: Caddy rewrites the outgoing request's `Host` header to `auth.example.com` so the remote Caddy can route/SNI-match it, and without an override `X-Forwarded-Host` picks up that rewritten value instead of the original site's host. Confirmed live: Authelia evaluated *every* protected domain as if the request were for `auth.example.com` itself (which typically has `policy: bypass` in `access_control.rules` so its own login portal isn't gated behind itself) — so every domain behind the remote instance silently passed through with no 2FA prompt, regardless of that domain's own policy. Fix: pin the forwarded headers to the original request explicitly instead of trusting Caddy's default derivation: ``` forward_auth https://auth.example.com { uri /api/authz/forward-auth copy_headers Remote-User Remote-Groups Remote-Name Remote-Email header_up X-Forwarded-Method {method} header_up X-Forwarded-Proto {scheme} header_up X-Forwarded-Host {host} header_up X-Forwarded-Uri {uri} } ``` This only affects the remote-Authelia path — same-machine `authelia:9091` snippets (`services/authelia.sh`) are a single hop and don't need it. Sets two out-params (not `local` — read them after the call returns) so the caller can tell whether Caddy actually ended up fronting the service: ```bash CADDY_SERVICE_CONFIGURED # true/false CADDY_SERVICE_MODE # "local" or "remote" (only meaningful if configured) ``` Use this to skip opening a host firewall port for a service Caddy already fronts *locally* (it reaches the service over `host.docker.internal`, not the network) — but still open it when `CADDY_SERVICE_MODE` is `"remote"`, since a remote Caddy machine needs to reach this host over the network instead. See `services/asterisk.sh` for the reference pattern: it decides the Caddy question *before* building firewall rules, not after, so the answer is known in time (in droplet mode it hand-builds its own site block and sets the same flag itself, for the reasons noted above). ### UFW enable ```bash ensure_ufw_enabled ``` Call this **after** your service has already added its own `ufw allow` rules — it only flips UFW from inactive to active, it doesn't add rules for you. No-ops if UFW is already active or not installed. Always allows SSH first (reading the real port from `sshd_config` in case it's non-default) before enabling, so this can't lock out the session running the installer. ### Closing a port to the internet without also closing it to Caddy ```bash ufw_allow_from_caddy_net PORT [PROTO] # PROTO defaults to tcp ``` When `CADDY_SERVICE_MODE` is `"local"` (see above) and you `ufw delete allow` a port because Caddy fronts it now, don't stop there — UFW rules apply to *all* interfaces unless scoped, and Caddy's own request to `host.docker.internal:PORT` is ordinary INPUT-chain traffic arriving over the `caddy_net` bridge, not the public internet. A bare `ufw delete allow` blocks that too and silently breaks the service (confirmed live: closing the web admin port outright took Caddy down with it). Call `ufw_allow_from_caddy_net` right after the `delete` to re-open the port scoped to just `caddy_net`'s subnet — reachable from Caddy, not from the internet. See `services/asterisk.sh` for the pattern. ### README generation ```bash write_readme "$DIR" << 'MD' # Title Content MD ``` Writes `$DIR/README.md` (creates the directory if needed). No-ops in DRY_RUN. Every Docker service should call this so `~/docker//README.md` is self-documenting on the deployed box. **Companion doc files.** If `services/.md` exists next to `services/.sh`, `write_readme` appends its contents automatically — no per-service code needed to opt in, just add the file. It's outside `setup.sh`'s `services/*.sh` glob so it never registers or runs on its own; it's purely markdown that gets tacked onto the generated README. Use it for walkthroughs that don't depend on anything chosen at install time (linking steps in a third-party UI, multi-account setup, troubleshooting notes) — content like that bloats the heredoc without adding anything install-specific. Keep the heredoc for content that *does* depend on install-time values (the actual port chosen, generated credentials, etc.); use `services/.md` for everything else. See `services/traccar.md` for the reference example. ## Categories | Group | Purpose | |-------|---------| | `base` | CLI packages installed on every box | | `homelab` | Core infrastructure — reverse proxy, auth, intrusion prevention | | `utilities` | Self-hosted web apps — budget, DNS, files, monitoring, VPN, etc. | | `media` | Media servers, photo backup, disc ripping | | `cameras` | NVR and camera tooling (Frigate) | | `gaming` | Game servers, cloud gaming (Wolf), emulation | | `extras` | Non-Docker tools and scripts | | `backup` | Backup solutions | ## Authelia SSO — which services need it Some services have their own login screens; others have none and need Caddy to gate them via Authelia. **Protecting more than one apex domain from the same box — same instance, not a second one.** `services/authelia.sh`, re-run against an existing install, offers "Add another protected domain to this instance": it appends a new `access_control.rules` entry and a new `session.cookies` entry (both are YAML lists — Authelia natively supports multiple independent cookie scopes) plus a Caddy `auth.` portal block for the new domain, all on the **same** Authelia + Redis container. Each domain gets its own login/session (no cross-domain SSO between them) and shares one user database, without the RAM cost of a second full Authelia+Redis stack — the right choice whenever the domains are going to live on the same machine anyway. See `add_authelia_domain()` in `services/authelia.sh`. **Running a genuinely separate instance (e.g. one per machine).** `services/authelia.sh` runs standalone on any box (`sudo bash authelia.sh`, same pattern as `crowdsec.sh`) and `asterisk.sh` already auto-detects a local install (`if [ -d "$DOCKER_DIR/authelia" ]`), switching from the remote-Authelia `forward_auth` flow to the local `import authelia` snippet automatically — so a second, fully independent instance on another machine (e.g. a droplet, for resilience if the first machine goes down) works with no code changes. Use this instead of the same-instance approach above when the two domains are on different machines, not just different domains on one machine. The one real constraint for genuinely separate instances: Authelia's session cookie is scoped to `AUTHELIA_DOMAIN` (the apex domain entered at install time) with `includeSubDomains`-style matching, and the portal itself lives at `auth.${AUTHELIA_DOMAIN}`. **Two independent instances must not share the same `AUTHELIA_DOMAIN`.** If they did, both would try to claim the same `auth.` hostname (DNS can only point that at one machine) and the same cookie scope with completely separate session stores — users bouncing between subdomains fronted by different instances would see confusing repeated logins as each instance's cookie gets overwritten/rejected by the other's. Give each instance either a genuinely separate apex domain, or a distinct subdomain tree the other instance doesn't also claim. (This constraint doesn't apply to the same-instance, multiple-domains approach above — each domain there gets its own cookie entry by design, which is exactly what avoids the collision.) **Has built-in auth — no Authelia needed:** `emby`, `jellyfin`, `audiobookshelf`, `immich`, `mealie`, `actualbudget`, `homeassistant`, `portainer`, `meshcentral`, `traccar`, `uptimekuma`, `filebrowser`, `wg-easy`, `ntfy` (configurable), `gitea` **Native OIDC login as an addition, not a Caddy gate — `gitea`'s pattern.** Some apps with their own built-in login *also* have their own "add an OAuth2/OIDC provider" setting — a genuinely different integration from both the forward_auth gate above and the "Enable OpenID" client-registration flow below. `services/gitea.sh`'s `_gitea_offer_authelia_sso()` is the reference: if Authelia is installed, offers to register Gitea as an OIDC client (via `services/authelia.sh`'s `_authelia_provision_oidc_client()` — the same non-interactive, out-param-returning core that `_authelia_add_oidc_client()`'s menu flow uses) and then runs `gitea admin auth add-oauth` itself to add Authelia as an authentication source — no manual web-UI copy-paste on either side, matching this repo's "no manual wizard" philosophy elsewhere in gitea.sh (admin account/token creation). Local login keeps working unchanged; this only adds an extra button on the existing login page. Reuse `_authelia_provision_oidc_client()` (guarded by `declare -F`, same convention as chaining into another service's `install_()`) for any future service with its own native OIDC field, instead of duplicating Authelia's client-secret-generation/config-patching logic again. **No built-in auth — should be protected:** `magicmirror`, `wolf-pair`, `js99er`, `drum-rhythm-game`, `iopaint`, `paintplus`, `stirling-pdf`, `wolf` (web UI). Each of these prompts "Protect X with Authelia SSO? (y/n)" and passes `import authelia` as `configure_caddy_for_service`'s extra block when accepted. `security-dashboard` is Authelia-protected unconditionally (not asked — baked into its own Caddy block, since it exposes Asterisk/CrowdSec data). `asterisk` offers the same protection for its web admin, with a choice between a local `import authelia` and a remote `forward_auth` (see the remote-Authelia note earlier in this file). `sky-cam` was previously listed here but has no Caddy integration or web login of any kind — it's a non-Docker batch/cron script that renders timelapse videos and posts them to Mattermost, so there's nothing on it for Authelia to protect. Removed from this list; if it grows a web UI in the future, add it back and wire up the same prompt other services here use. For services without built-in auth, prompt the user before calling `configure_caddy_for_service` and pass `import authelia` as the extra block if Authelia is installed and the user wants SSO protection: ```bash local EXTRA_BLOCK="" if [ -d "$DOCKER_DIR/authelia" ]; then local _use_auth="" prompt_yn "Protect MagicMirror with Authelia SSO? (y/n):" "y" _use_auth [[ "$_use_auth" =~ ^[Yy]$ ]] && EXTRA_BLOCK=" import authelia" fi configure_caddy_for_service "MagicMirror" "8081" "mirror" "$EXTRA_BLOCK" ``` **Authelia "stay logged in" / kiosk mode:** Edit `~/docker/authelia/config/configuration.yml` and set a long `remember_me_duration`. Users then check "Remember me" once on login and the session persists through reboots (Redis stores the session in a volume): ```yaml session: secret: 'your-existing-secret' remember_me_duration: 1y # add or update this line expiration: 1h inactivity: 5m cookies: - domain: 'example.com' authelia_url: 'https://auth.example.com' ``` After editing: `docker compose -f ~/docker/authelia/docker-compose.yml restart` ## Non-Docker services Not everything is a container. For apt-based or git-clone–based services, skip `require_docker` and the Docker helpers. See `services/base.sh` (apt packages + Charm repo) and `services/crowdsec.sh` (official apt repo) as reference patterns. For non-Docker services the default `is_installed` check in `setup.sh` looks for `$DOCKER_DIR/$name`, which won't exist. Add a case to the `is_installed()` function in `setup.sh` so the `[installed]` marker appears correctly in the menu: ```bash # In setup.sh → is_installed() my-tool) command -v my-tool >/dev/null 2>&1 ;; ``` Docker services use the default case and don't need an entry. ## DRY_RUN convention Every `install_*` function must check `$DRY_RUN` before touching the filesystem, installing packages, or starting containers. The pattern is: ```bash if [ "$DRY_RUN" = true ]; then echo "[DRY-RUN] Would do X" echo "[DRY-RUN] Would do Y" return 0 fi ``` Put the check early — after any pure-display output (banners, info text) but before the first write. ## Update vs. fresh reinstall on rerun Every service should detect an existing install at the top of its `install_()` — after the `DRY_RUN` check, before any prompts — and offer `prompt_reinstall_mode` instead of silently re-running every prompt (domain, secrets, firewall, Authelia, extras...) from scratch. What counts as "already installed" is service-specific: usually `docker-compose.yml` and `.env` both existing in the service's `$DOCKER_DIR/` directory. ```bash if [[ -f "$DIR/docker-compose.yml" && -f "$DIR/.env" ]]; then local MODE="" prompt_reinstall_mode MODE case "$MODE" in update) # Refresh vendor files / config templates, rebuild, done. # Do NOT touch .env, firewall rules, or Caddy/Authelia config. ... return 0 ;; cancel) log_info "Leaving the existing install as-is." return 0 ;; fresh) ;; # fall through to the full install flow below esac fi ``` `update` should be genuinely non-destructive: refresh whatever the service vendors or templates (Docker image sources, config templates, `docker-compose.yml`) and rebuild/restart, but never touch `.env`, firewall rules, or reverse-proxy/SSO config that's already in place. If the vendor-copy or `docker-compose.yml`-generation logic is more than a few lines, factor it into a helper function so the fresh-install path and the update path share one copy instead of drifting apart — see `_asterisk_refresh_vendor_files`/`_asterisk_write_compose` in `services/asterisk.sh` for the reference pattern. `cancel` must leave the install completely untouched — it's the default for a reason (a stray Enter on a service you're just checking on shouldn't trigger anything). `fresh` runs the exact same flow a first-time install would, prompts included. ## Multi-instance services Any service where running two genuinely separate copies is a real use case (two Mattermost teams, two WordPress sites, two Traccar fleets, a music-only Emby alongside a movies one) should support it — this isn't opt-in per service, it's the default shape for anything that stores its own data and isn't inherently single-tenant (skip it for things like `caddy` or `crowdsec`, where a second instance wouldn't mean anything). **The pattern** (see `services/mattermost.sh` for the original, and `services/audiobookshelf.sh`/`services/emby.sh`/`services/mealie.sh`/ `services/traccar.sh`/`services/wordpress.sh` for more examples): the first instance keeps the plain name/directory/container/ports exactly as they'd be without any of this — zero behavior change for anyone with a single instance already installed. Only *choosing* to add a second introduces suffixed naming. `services/wordpress.sh` is the one exception that requires a name from every instance including the first — reasonable for a brand-new service with no existing single-instance installs to stay compatible with, but not the default choice for an established service. ```bash local DIR="$DOCKER_DIR/myservice" local INSTANCE_SUFFIX="" CONTAINER="myservice" local WEB_PORT="9000" if [ -d "$DIR" ]; then echo "" echo " MyService is already installed at $DIR." echo " 1) Manage that install (update / full reinstall / cancel)" echo " 2) Add a NEW, separate MyService instance alongside it (its own" echo " server and data — full isolation)" echo "" local _TOP_CHOICE="" prompt_text " Choice [1/2]:" "1" _TOP_CHOICE if [ "$_TOP_CHOICE" = "2" ]; then local _suffix="" while true; do prompt_text " Short name for the new instance (letters/numbers/hyphens):" "" _suffix _suffix="$(echo "$_suffix" | tr -cs 'a-zA-Z0-9-' '-' | sed 's/^-*//;s/-*$//')" [ -z "$_suffix" ] && { log_warning "Name can't be empty."; continue; } [ -d "$DOCKER_DIR/myservice-$_suffix" ] && { log_warning "myservice-$_suffix already exists — pick another name."; continue; } break done INSTANCE_SUFFIX="$_suffix" DIR="$DOCKER_DIR/myservice-$_suffix" CONTAINER="myservice-$_suffix" while ss -tlnH "sport = :${WEB_PORT}" 2>/dev/null | grep -q .; do WEB_PORT=$((WEB_PORT + 1)) done log_info "New instance: $DIR (port $WEB_PORT)" fi fi ``` Everything downstream — `container_name`, `hostname`, published ports, the Caddy subdomain default passed to `configure_caddy_for_service`, log/prompt text, the generated README's title — reads from `$CONTAINER`/`$WEB_PORT`/ `$INSTANCE_SUFFIX` instead of the literal service name, so it's already correct for either the first instance or a named one with no further branching. **Databases: dedicated per instance, not shared.** `services/wordpress.sh` started as one shared MariaDB container with a separate database per site (same resource-sharing idea as the shared `coturn` below), and was deliberately changed away from that. The reason generalizes: Kopia's generic backup (`services/backup.sh`) stops a service's *container* to get a consistent snapshot, so a shared database instance backs up — and would have to be restored — as one unit covering every instance's data at once, not one instance independently. A dedicated database container per instance costs more RAM (a full container each instead of one instance split across several) in exchange for real backup/restore isolation. Data is typically isolated either way (separate database + user regardless), so the shared-vs-dedicated choice is about the container/process and its backup blast radius, not about the data being mixed. Default to dedicated per instance; only share if a service's own architecture makes that awkward and the resource savings are worth the backup-coupling tradeoff. **Ports beyond a single one need more than one `ss` scan, but never port-by-port for a large range.** A service publishing two or three fixed ports (`services/emby.sh`, `services/mattermost.sh`'s web+Calls-UDP ports) just runs the same `ss` scan once per port. A service publishing a large *range* (`services/traccar.sh`'s ~150-port device-protocol range) can't be scanned port-by-port — instead shift the whole range by a fixed offset per instance, sized off how many `$DOCKER_DIR/*` directories already exist (`find "$DOCKER_DIR" -mindepth 1 -maxdepth 1 -name '*' -type d | wc -l` — the `-mindepth 1` matters, since without it `find` also matches `$DOCKER_DIR` itself if its own basename happens to start with the service name). Check whether the *first* instance's range carves out exclusions for another service's fixed ports (traccar's does, for Asterisk's AMI/SIP ports) — a large enough offset on additional instances usually clears those same fixed ports automatically, so the exclusions typically don't need to be repeated for instance 2+. **Docker labels used by sidecar tooling need per-instance scoping too, not just container names.** `services/traccar.sh`'s `autoheal` sidecar watches containers by a Docker label that's visible host-wide, not scoped to a compose project — two instances both using the literal `autoheal` label would each try to restart the *other* instance's container too. Give the label itself a per-instance value (`autoheal--`) and point that instance's `autoheal` container at the same value via `AUTOHEAL_CONTAINER_LABEL`, the same way container names get suffixed. **Verify port/count logic by actually running it, not just by reading it.** Both real bugs caught while building this pattern into `services/traccar.sh` — the `find` matching `$DOCKER_DIR` itself, and the port-scan needing a genuinely free-vs-taken state to prove it increments — were things code review alone would have missed. Install two instances in sequence (a fake `docker`/`ss` shim standing in for a live daemon is fine) and confirm the second one's directory, container names, and ports are actually distinct before trusting the logic. ## Port collision avoidance With 70+ services in this repo, several ship the same default port — `emby` and `jellyfin` both default to 8096, `changedetection` and `frigate` both default to 5000, `arm` and `nextcloud` both default to 8080. Nothing enforced those defaults were actually free on the host: whichever service started its container second would fail to bind ("port is already allocated") instead of landing on the next free port. Confirmed live: installing `jellyfin` after `emby` (or vice versa) writes a `docker-compose.yml` claiming a port the other service's container already holds, and it only fails at `docker compose up` time — not at install time, and not with any warning from the installer itself. **Every service that publishes a fixed host port must scan for a free one before writing `docker-compose.yml` — on every install, not only when adding an explicit additional instance of itself.** Two shared helpers in `lib/common.sh` do the work: ```bash port_in_use PORT [PROTO] # true if something's already listening; PROTO defaults to tcp, pass "udp" for UDP-only ports find_free_port VARNAME START [PROTO] # scans upward from START, writes the free port back into VARNAME ``` Single-port services just call `find_free_port`: ```bash local WEB_PORT="8080" find_free_port WEB_PORT "$WEB_PORT" ... - "${WEB_PORT}:8080" # host side scanned; container-internal side stays literal ``` Services with multiple ports that must move together (a web port + an agent/RTSP/MQTT port, etc.) loop over `port_in_use` directly instead, the same pattern `services/meshcentral.sh` and `services/unifi.sh` use: ```bash while port_in_use "$WEB_PORT" || port_in_use "$AGENT_PORT"; do WEB_PORT=$((WEB_PORT + 1)) AGENT_PORT=$((AGENT_PORT + 1)) done ``` On a normal single-install host this is a silent no-op — the default port is free, so the variable comes back unchanged and nothing about the install looks any different. It only changes behavior when something else already holds the port, which is exactly the case that used to fail at container-startup instead of being handled at install time. **Standalone-mode stub.** Every service also carries a standalone bootstrap fallback (`if [[ -f "$_COMMON" ]]; then source it; else fi`, for `sudo bash services/.sh` with no sibling files sourced) that duplicates the helpers it needs. `port_in_use`/`find_free_port` get the same treatment — copy the same two function bodies into that `else` block, matching how `log_info`, `prompt_text`, `configure_caddy_for_service`, etc. are already duplicated there. **Only the host side of a `"HOST:CONTAINER"` port mapping changes.** The container-internal port is fixed by the application itself and stays a literal number; only the host-published side becomes `${WEB_PORT}` (or whatever the variable is named). Watch for the same literal number showing up elsewhere in the file needing the same treatment: `configure_caddy_for_service` calls (container-internal side stays literal; a *bare*-port host-networking upstream, like `services/lyrion.sh`'s first instance, does need the variable), generated companion scripts (`services/koha.sh`'s `post-setup.sh`, `services/rustdesk.sh`'s relay-host messaging), `.env` values baked into client-facing config (`services/wg-easy.sh`'s `WG_PORT` env — WireGuard bakes the port into every generated peer config's `Endpoint =` line, so it must track the *actual* published port, not just the host-side compose mapping), and every `echo`/README line that prints `http://localhost:`. **Quoted (`<< 'MD'`) README heredocs don't interpolate — check before editing.** A `write_readme ... << MD` (unquoted) heredoc already interpolates `${WEB_PORT}` directly. A quoted `<< 'MD'` heredoc doesn't, and converting it means escaping *every* backtick used for inline-code formatting (`` \`...\` ``) — miss one and bash tries to execute it as a command substitution the next time the heredoc is read, the same class of bug the coturn.sh backtick incident was (see `attic/coturn.sh`'s `write_readme` call). For a README with only one or two backticks, escaping them is fine. For one with many (`services/iopaint.sh`'s model reference table), it's safer to leave the heredoc quoted and patch the port into the *written* `README.md` afterward instead: ```bash [ "$WEB_PORT" != "8100" ] && sed -i "s/localhost:8100/localhost:${WEB_PORT}/g" "$IOPAINT_DIR/README.md" ``` **`network_mode: host` services can only scan what the app itself lets you override.** Host networking has no port *remapping* — whatever the app binds to on its fixed internal port is what's exposed, so `find_free_port` only helps for ports the app takes as configurable env vars. `services/lyrion.sh`'s `HTTP_PORT` env is genuinely configurable (LMS honors it as the actual bind port under host networking too — see its `_HTTP_PORT_INTERNAL` handling, which must track the scanned port rather than assuming bridge-mode's fixed `9000`), but its CLI (9090) and player (3483) ports are hardcoded in the image with no override — a collision there can only be warned about with `port_in_use`, not silently fixed. `services/homeassistant.sh` is the same shape: bridge mode (the default) scans freely; host mode (opt-in, for LAN device discovery) can only warn. **Caddy is the one deliberate exception — never auto-scanned.** `services/caddy.sh` keeps 80/443 fixed and only warns via `port_in_use` if they're already taken. Every other service either points HTTPS clients at Caddy implicitly (browsers assume 443) or gets routed through it by domain; silently moving Caddy itself to a random port would leave nothing listening at the address any client actually tries, which is strictly worse than the collision it would be "fixing." If 80/443 are already bound, that's a real conflict (another web server on the host) the user needs to resolve directly. ## Chaining into another service from within your own A service can call another service's `install_()` directly as a convenience step at the end of its own flow, instead of making the user remember to separately run `sudo ./setup.sh ` afterward. `services/asterisk.sh` does this for `services/security-dashboard.sh` and `services/pstn-trunk.sh` — after Asterisk itself is installed/updated, it asks once whether to also set up the dashboard and/or a PSTN trunk (or, if either is already installed, silently re-invokes it so it gets refreshed as part of the same run — its own `prompt_reinstall_mode` gate decides update vs. skip, so this never re-asks the target service's detailed prompts unless the user is actually setting it up fresh). The target service **keeps its own `register_service` call** — it stays independently selectable/invocable exactly as before (`sudo ./setup.sh pstn-trunk` still works standalone). Chaining is purely additive, not a replacement for the target's own entry point, so nothing breaks for anyone already relying on running it directly. Guard every cross-file call with `declare -F`, since a service can also run completely standalone (`sudo bash asterisk.sh`, no `setup.sh`, no sibling `services/*.sh` files sourced at all): ```bash if declare -F install_security-dashboard >/dev/null 2>&1; then install_security-dashboard fi ``` Only chain in one direction, and only when the relationship is genuinely one-way (the target is meaningless without the caller already installed — `pstn-trunk.sh` itself says so in its own error message when Asterisk isn't present). Don't have both sides call each other. ## .env files and secrets Generate passwords with `generate_password` (never hardcode them). Write secrets to `.env` files in the service directory, owned by `ACTUAL_USER`, permissions 600. Document every variable with a comment in the `.env` heredoc so the user knows what to change later. ## Caddy network wiring Services that need to reach Caddy (or each other) over Docker networking should join the `$SITE_CADDY_NET` network. Add to `docker-compose.yml`: ```yaml networks: caddy_net: external: true name: ${CADDY_NET:-caddy_net} ``` And read the network name from `.env` using `CADDY_NET=$SITE_CADDY_NET`. `external: true` means *this* service expects the network to already exist — it doesn't create it. `require_docker` creates it for you (via `ensure_caddy_network` in `lib/common.sh`) the first time any service calls it, so as long as your `install_()` calls `require_docker` before `docker compose up` (it always should), the network is guaranteed to exist regardless of whether Caddy itself has been installed yet. **`network_mode: host` services (e.g. `asterisk`) don't join `caddy_net` at all** — Caddy reaching them (or anything else on the host network) needs `host.docker.internal:PORT` in the Caddyfile, not `localhost:PORT` or a container name. Caddy's own compose file (`services/caddy.sh`) sets `extra_hosts: host.docker.internal:host-gateway` so that hostname resolves; `configure_caddy_for_service`'s bare-port upstream case already does this for you — don't hand-roll `localhost:PORT` in a Caddy site block. ## coturn (TURN/STUN) relay — dedicated per service, not shared Any service that needs a TURN server for WebRTC/SIP NAT traversal runs its **own dedicated** coturn container. There is no shared coturn service to install or point at — `services/coturn.sh` was tried and retired; it's parked at `attic/coturn.sh` (outside `services/*.sh`'s glob, so it never registers or appears in the menu — see `attic/README.md`). Sharing one instance saved a container per consumer (~40MB) but was a single point of failure every consumer depended on, and needing a dedicated per-consumer long-term-credential user added real setup complexity for a small RAM win. Don't reintroduce it — give every new WebRTC/SIP-capable service its own coturn, following the pattern below. **The collision this pattern has to avoid:** `asterisk` and `mattermost` each embed a dedicated coturn container (`network_mode: host`, each with its own relay port range) — confirmed live, two independent coturns' default ranges used to overlap by ~100 UDP ports, so running both on one box meant a coin-flip over which service's active call lost its media relay. Static default ranges alone don't solve this; something has to pick non-overlapping ranges per box. **Use `find_free_coturn_range` (`lib/common.sh`) to size the range, not a hardcoded default:** ```bash local MY_COTURN_MIN_PORT=49152 MY_COTURN_MAX_PORT=49252 find_free_coturn_range MY_COTURN_MIN_PORT MY_COTURN_MAX_PORT 100 49152 [[ "$MY_COTURN_MIN_PORT" != 49152 ]] && \ log_info "Dedicated coturn relay range shifted to ${MY_COTURN_MIN_PORT}-${MY_COTURN_MAX_PORT} to stay clear of another coturn already on this box." ``` Unlike a single fixed host port (`find_free_port`'s job — coturn's relay range isn't a statically bound listening socket you can detect with a live `ss`/socket scan), `find_free_coturn_range` scans every `$DOCKER_DIR/*/.env` for a `TURN_MAX_PORT=` line and starts the new range 50 ports past the highest one found — so it works across every coturn-owning service on the box (Asterisk, each Mattermost instance, yours), regardless of install order. Persist the chosen range as `TURN_MIN_PORT=`/`TURN_MAX_PORT=` in your own `.env` so later installs' scans see it, and on an `update` rerun read those same keys back from the existing `.env` instead of re-scanning — a live coturn container must never silently move to a different port range (breaks in-flight/repeat sessions on whatever client already has the old range's ports allowed through its own firewall/NAT). See `services/asterisk.sh`'s and `services/mattermost.sh`'s `EMBEDDED_COTURN_MIN_PORT`/ `MM_COTURN_MIN_PORT` handling for the reference pattern, including the `MODE != "update"` gate that scans only on a fresh install. **Auth mode — long-term credentials (`--lt-cred-mech`) or HMAC (`--use-auth-secret`), your choice per instance:** coturn doesn't support running both on one instance at once, but since each service now owns its instance outright, this is a free per-service choice — no shared-instance constraint forcing one mode across every consumer. `services/asterisk.sh` uses `--lt-cred-mech` (fixed username/password, simplest to bake into a SIP device's config); `services/mattermost.sh` uses `--use-auth-secret` (HMAC), matching the Calls plugin's own "TURN Static Auth Secret" field. Check the consuming app's own TURN settings UI for which fields it actually exposes before picking. **Legacy installs still on the old shared coturn:** an `update` rerun on an install that predates this repo's dedicated-coturn-only model (no `coturn:` block in its `docker-compose.yml`) must not try to silently migrate or "heal" it — there's no shared coturn service left in this repo to heal it against. Leave it running exactly as-is (an `update` never touches `.env` anyway) and point at a full/fresh reinstall as the migration path, which generates a new dedicated coturn container with fresh credentials. See the `_HAD_EMBEDDED_COTURN` handling in `services/asterisk.sh` and `services/mattermost.sh` for the reference pattern — detect via `grep -q '^ coturn:' docker-compose.yml` before regenerating it, same as any other non-destructive `update` path in this file.