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Give each test worker its own scratch folder in the #3025 and #3029 tests (issue #3025)
Both modules wrote into one shared folder under settings.base_dir and deleted
it after every test. Under xdist, one worker's cleanup removed files another
worker was still serving, so tests failed at random with a 404. The folder name
now includes the process ID.
The Slice and Open in Slicer actions mint a short-lived token and put it in
the URL, because a protocol handler cannot carry an Authorization header.
That token was spent by the first request to reach the endpoint, which made
the handoff depend on the slicer fetching the URL exactly once. Nothing
guarantees that: Bambu Studio's downloader retries three times after a
failed attempt, transfers get resumed, on-access scanners fetch. The first
request won and the slicer was handed a 403.
verify_slicer_download_token takes a keyword-only single_use flag. The
default still consumes via DELETE...RETURNING; single_use=False verifies
with a SELECT and leaves the row for the rest of its five-minute TTL. The
stored row is the same either way, so the endpoint decides, not the mint.
The three protocol-handler downloads pass single_use=False: a library file,
an archive's sliced 3MF, an archive's source 3MF. Resource binding and
expiry are untouched. The two browser downloads keep consuming, because
what they hand over is itself consumed -- the prepared printer bundle is
deleted the moment it has been streamed.
Also: add "/source-dl/" to PUBLIC_API_PATTERNS. Those patterns match by
substring and the source 3MF route's segment is source-dl, which does not
contain "/dl/", so with auth enabled the middleware rejected the slicer's
header-less request before the route's token check ran. Open source 3MF in
slicer could never work on an install with authentication on.
maziggy