App data

Every app has one JSON document for small state that belongs to the app: saved settings, a last-run timestamp, a flag your app set itself. It needs nothing switched on.

Size	Up to 256 KiB.
Shape	One JSON object. No keys, listing or queries.
Lifetime	Survives restarts, redeploys and rollbacks.

import toft

settings = toft.data.get() or {"period": "monthly"}
toft.data.set({**settings, "period": "weekly"})

get() returns None when nothing is stored, which is different from a stored {}. clear() removes the document and returns the app to storing nothing.

Two writers

set() is last-write-wins. If a job and the web process both write, use update(): it reads, applies your change and writes back conditionally, retrying if someone else wrote in between.

toft.data.update(lambda s: s.update(runs=s.get("runs", 0) + 1))

For explicit control, read() returns the document with its version, and set(doc, if_version=v) raises toft.VersionConflict if the stored version has changed. if_version=0 means “only if nothing is stored”.

What it is not for

App data is not a database. Anything you need to search, or anything per user, belongs in a real database.

In the UI

Settings → Saved data shows whether the app has saved anything, its size and when it changed. It never shows the contents. If your app saved something its own startup code cannot read, people who can edit the app can Clear it; a redeploy will not fix that.