Files
Schulcloud-MCP/docs/CLI.md
MechaCat02 3e44e66dde Survive a first full crawl: poll, time out on silence, retry downloads
The first full crawl with the file manager ran 14 minutes, downloading every
file once, and broke in three ways:

- `schulcloud refresh` reported "fetch failed" for a crawl that was
  succeeding: Node's fetch abandons a response without headers after five
  minutes. POST /api/refresh takes wait:false and the CLI polls /api/status;
  refresh_index answers after 50 s and leaves the crawl running, and
  index_status says when a first crawl is under way.
- Downloads were bounded by the 30 s request timeout, which cut 11 MB scans
  off mid-transfer. They now time out on 30 s of silence instead.
- Failures were recorded once and never retried. A download failure is now
  retried on the next crawl while an extraction failure stays final, and PDF
  text containing NUL, which Postgres refuses, is stripped.

On the re-crawl all six failed files succeeded; only two videos above the
mirror cap stay metadata-only, by design. 137 tests.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 20:19:16 +02:00

6.3 KiB

The schulcloud CLI

Browses and mirrors your Schulcloud files from a laptop, by talking to the schulcloud-mcp server on the Pi.

Why it goes through the Pi

The CLI never talks to Schulcloud. It holds no jwt cookie, no Schulcloud credential of any kind — only this server's bearer token.

That is not an accident of layering; it solves a real problem. A Schulcloud session dies after two hours of inactivity, and a CLI process lives for seconds, so a CLI with its own token would be dead most times you reached for it. The Pi already keeps one session alive around the clock. Routing through it means one session, one keepalive, and one place to paste a fresh cookie once a month.

It also means the laptop cannot accidentally end the server's session: nothing here can call logout.

Setup

schulcloud login --server https://mcp.example.org --token <MCP_AUTH_TOKEN> --dir ~/Schulcloud

The token is the same MCP_AUTH_TOKEN the Claude connector uses — one token guards both surfaces. login verifies it before saving, so a typo fails immediately rather than on first real use. Config is written to ~/.config/schulcloud/config.json with mode 0600.

SCHULCLOUD_SERVER, SCHULCLOUD_TOKEN and SCHULCLOUD_SYNC_DIR override the file, for CI or one-off invocations.

Commands

schulcloud status                  how fresh the server's index is
schulcloud ls [--course <id>] [--long]
schulcloud get <fileId> [--out <path>]
schulcloud sync [--dry-run] [--full] [--prune] [--dir <path>] [--jobs <n>]
schulcloud refresh [--course <id>] [--force]

ls --long prints file ids, which is what get takes.

--course accepts a course or a room id — rooms ("Räume") are mirrored alongside courses, with their files under the room's name rather than a course's.

refresh asks the server to re-read Schulcloud. Pass --course when you know what changed: that is a handful of requests, where a full re-crawl reads every course. The server refuses a repeat within a minute unless you pass --force. A full re-crawl can take many minutes — the first one downloads every file, file-manager folders included — so refresh starts it and then polls the server's status, printing a note every half minute, rather than holding one request open (which Node's fetch abandons after five minutes).

The file manager (fs)

The Schulcloud file manager ("Dateien") — Persönliche, Kurs-, Team- and Geteilte Dateien — browsed like a filesystem, live:

schulcloud fs ls [path] [--long]
schulcloud fs tree [path] [--depth <n>] [--max-folders <n>]
schulcloud fs find <name> [--path <path>] [--type file|folder] [--long]
schulcloud fs get <path> [--out <path>] [--force] [--jobs <n>]
$ schulcloud fs ls /courses
$ schulcloud fs tree "/courses/FIA24B - SK (Rh)"
$ schulcloud fs find "*Erben*" --path /courses
$ schulcloud fs get "/courses/FIA24B - SK (Rh)/02_Erbrecht" --out ~/Erbrecht

The tree is /my, /courses/<course>, /teams/<team> and /shared; the German names ("/Kurs-Dateien") work too. Names may contain / — course names often do — and still resolve; any segment may also be an id from --long.

fs find matches any part of a name, or, given * or ?, the whole name as find -name does. fs get on a folder downloads everything below it, keeps the structure, and skips files already present at the same size — so re-running it resumes. Each folder is one page load on the server, so large trees take a while.

sync mirrors these files too, under <course>/Kurs-Dateien/…, Persönliche Dateien/…, Team-Dateien/<team>/… and Geteilte Dateien/, once the server's index includes them (INDEX_FILE_MANAGER, on by default).

How sync works

It is a one-way mirror, not a two-way sync, and that follows from the data rather than from laziness: Schulcloud file records are immutable — editing a file upstream produces a new record — so there is no content versioning, no conflict resolution and no merge. "Download what I do not have" is the whole algorithm.

Local state lives in .schulcloud-sync.json at the root of the sync directory, keyed by file record id with the path as derived output. That is what makes renames cheap: when a teacher renames a board column, the file moves on disk instead of being downloaded again under a new name and left duplicated under the old one.

What it checks, and why only that:

  • Size, not a checksum. The download endpoint exposes no ETag and Schulcloud publishes no hash, so verifying content would mean re-downloading every file to learn what it already told us. Size reliably catches the failure that actually happens — a truncated or interrupted download — and costs a stat.
  • Downloads land on a .part neighbour and are renamed into place, so an interrupted run never leaves a half-file that a later run mistakes for complete.

Deletions are not propagated by default. A teacher removing a worksheet is not a reason to destroy your copy of it; sync reports those as "gone upstream, kept". Pass --prune to actually delete them.

--dry-run prints exactly what would happen, writes nothing, and does not advance the cursor.

Cursors

The server's sync cursor is a crawl generation id, not a timestamp. This is deliberate and measured: GET /course-rooms/{id}/board returns the request time as updatedAt for most elements, so a timestamp cursor would report every board as changed on every crawl. Comparing generations by identity also detects deletions, which no timestamp scheme can.

--since on the server API accepts an ISO date for convenience, resolved to the nearest generation — but correctness never depends on it.

If the server no longer recognises your stored cursor it returns 409 rather than silently treating everything as new, so you are never tricked into re-downloading the world. Run sync --full deliberately in that case.

Paths

Mirror paths are Course/Board/Card/filename, built by core/paths.ts.

Every component of that path originates in Schulcloud — course titles, card titles and filenames are all user-supplied upstream — so each is reduced to a single safe path component, and the result is re-checked against the sync root before anything is written. A file named ../../.ssh/authorized_keys cannot escape, and sync refuses such an entry rather than writing it.