Files
go-nc-exapp/README.md
T

92 lines
4.7 KiB
Markdown
Raw Permalink Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
# go-nc-exapp
Shared Go library for Nextcloud ExApp Services: AppAPI authentication, OCS JSON calls, per-user ExApp preferences, and an optional Required Groups Access Gate.
Import: `gitea.neitzel.de/konrad/go-nc-exapp` (package `gonexapp`).
## Scope
**Included**
- **Credentials** — Nextcloud base URL, AppAPI secret, and requesting user identity
- **AuthHeaders** — outbound AppAPI authorization for OCS and other Nextcloud calls
- **WithUser** — credentials scoped to a specific requesting user
- **UserFromRequest** — extract the requesting user from inbound AppAPI-proxied requests
- **OCSClient** — authenticated OCS calls that always append `format=json`
- **AppAPIPreferences** — parameterized get/set of a string ExApp preference (caller supplies app id and key)
- **Access Gate** — optional Required Groups enforcement (`Wrap` + `Check`), English denied HTML for browsers (200 + `frame-ancestors 'self'`), positive membership cache; default skip for lifecycle paths and **`/js/`** top-menu scripts; env helpers for `REQUIRED_GROUPS` / `REQUIRED_GROUPS_CACHE_SECONDS`
- **Top Menu visibility** — `TopMenuAdminRequired` helper for deploy env `TOP_MENU_ADMIN_REQUIRED` (`0` / `1` for AppAPI top-menu OCS)
**Excluded**
- ExApp lifecycle HTTP routes (`/heartbeat`, `/enabled`, …) — the Gate *skips* these by default but does not implement them
- HaRP listen / `serve()` and unix-socket bootstrap
- Top-menu, script, and iframe UI registration
- WebDAV and file storage (see **go-nc-files**)
- **Visit** folder resolution (see **go-nc-files**)
## Usage
```go
cred := gonexapp.Credentials{
BaseURL: "https://nextcloud.example",
AppID: "myexapp",
AppVersion: "0.1.0",
AAVersion: "1.0.0",
AppSecret: os.Getenv("APP_SECRET"),
UserID: "alice",
}
prefs := gonexapp.NewAppAPIPreferences(cred, "myexapp", "savedDefault")
value, err := prefs.Get()
groupsEnv, groupsSet := os.LookupEnv("REQUIRED_GROUPS")
groups := gonexapp.ResolveRequiredGroups(groupsEnv, groupsSet, nil)
ttl := gonexapp.ParseCacheSeconds(os.Getenv("REQUIRED_GROUPS_CACHE_SECONDS"), gonexapp.DefaultCacheSeconds)
handler := gonexapp.AccessGate{Cred: cred, Groups: groups, CacheTTL: ttl}.Wrap(inner)
```
Each ExApp chooses its own preference keys; this library does not hardcode product-specific names.
Declare `REQUIRED_GROUPS` and `REQUIRED_GROUPS_CACHE_SECONDS` in the ExApp `info.xml` so Deploy options can set them.
The Gate skips `/heartbeat`, `/enabled`, `/init`, and any path under **`/js/`** (AppAPI top-menu bootstrap). Serve the registered top-menu script under `/js/…` so a non-member still loads it and can show Denied UI in the Nextcloud shell. API routes stay gated.
Denied HTML is **200** with `Content-Security-Policy: … frame-ancestors 'self'`. Without that header AppAPI’s proxy defaults to `frame-ancestors 'none'` and a denied iframe stays blank. Non-HTML denials remain **403**.
### Top Menu visibility (`TOP_MENU_ADMIN_REQUIRED`)
Declare in `info.xml` under `<environment-variables>`. At enable time the ExApp reads the env and passes `"0"` or `"1"` to AppAPI’s top-menu OCS `adminRequired`. Only `0` and `1` are valid; anything else falls back to `DefaultTopMenuAdminRequired` (`true` → admins only).
```go
adminRequired := gonexapp.TopMenuAdminRequired(
os.Getenv(gonexapp.EnvTopMenuAdminRequired),
gonexapp.DefaultTopMenuAdminRequired,
)
// use adminRequired in POST …/ui/top-menu when registering the menu entry
```
**Applying a change:** AppAPI registers the top menu when the ExApp receives `PUT /enabled?enabled=1`. Changing the deploy env alone does not update the menu entry.
1. Set the new value in Deploy options (UI) or `occ app_api:app:register … --env TOP_MENU_ADMIN_REQUIRED=…` / update deploy config.
2. Recreate or restart the ExApp container so the new env is present.
3. Re-run lifecycle: disable then enable the ExApp (UI or `occ app_api:app:disable` / `app_api:app:enable`), or `occ app_api:app:update … -e` after an image/info update.
Route `access_level` in `info.xml` is separate and only changes when AppAPI re-reads `info.xml` on register/update — not via this env.
Runnable package examples: `go test -run Example`.
## Domain language
See [CONTEXT.md](./CONTEXT.md) for AppAPI credentials, Requesting user, ExApp preference, OCS, Required Groups, Access Gate, and Top Menu visibility terminology.
## Testing
Unit tests use `httptest` fake OCS servers. No live Nextcloud is required for Library CI.
## Related
- **go-nc-files** — WebDAV, Working Folder, Saved Default, Visit resolution
- Workspace ADR 0013 — extraction from CheckDNS
- Workspace ADR `docs/adr/go-nc-exapp/0001-required-groups-access-gate.md` — Access Gate decisions