Blender is now a mandatory stage in draupnir's pipeline (Prime, 2026-09-28), and draupnir asked
for eight add-ons from extensions.blender.org: SurfacePsycho 0.10.4, CAD Sketcher 0.32.1,
3D-Print Toolbox 1.4.1, STEP Importer 1.2.1, Bool Tool 2.1.0, LoopTools 4.7.7, MeasureIt 1.8.4,
3MF Import/Export 2.7.7.
- stacks/blender/extensions.lock pins each by version and archive sha256.
- scripts/blender-extensions sync builds fv-ml1:/tank/blender-extensions/5.2/system with Blender's
own install-file, pre-warms and byte-compiles it, checks a read-only enable, then swaps it in.
It refuses while the GUI or a blender-run job holds the old directory.
- conf/scripts/startup/fleet_extensions.py enables every package in the System repo: in a timer
in the GUI (after the prefs load), and as --python ahead of the caller's args in
blender-run --extensions (a failed enable exits 1 before the caller's script).
- It also patches SurfacePsycho's sp_overwrite_segment_selection from eval() to literal_eval():
the eval walked past MCP safe mode (control: unpatched ran code, patched refuses).
- blender-run: --extensions (bind mounts via --mount so a missing source fails instead of being
created); USER/LOGNAME set, which CAD Sketcher's getpass needs.
- compose.yaml mounts the repo read-only and the hook into the GUI container. NOT yet deployed.
- scripts/blender-probes/extensions_acceptance.py: one operator run per add-on, safe-mode
compliant. Headless 8/9 online and with --network none; CAD Sketcher sketching is GUI-only.
A Python audit hook saw no network/process events (positive control fired).
draupnir review: the remote job dir was keyed on the basename alone, so two
local dirs with the same name shared one remote dir, and a rerun inherited
stale files. The dir is now <basename>-<8 hex of sha256(abs path)>, and it is
mirrored with rsync --delete, confined to that one directory. There is no rm on
a computed path. Verified: a file deleted locally is gone from the rerun's
remote dir. The /defaults stderr line is documented as harmless noise.
scripts/blender-run launches each call as a docker run --rm of the Blender
image on fv-ml1 GPU 3, capped at 64g / 48 CPUs. It needs no desktop and does
not affect the GUI container's lifecycle. --job DIR stages a local directory
to /tank/blender/jobs/<name>/, runs Blender with that as the cwd, and copies
results back. It always passes --python-exit-code 1, because Blender otherwise
exits 0 when a --python script raises (measured).
Tested headless: Cycles GPU and CPU, EEVEE via EGL, Workbench, an STL
round-trip, and exit codes (3, 7 and 1 pass through). There is no STEP
importer. Written for draupnir's design work, and indexed in FLEETTOOLS with a
detail file.
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