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fix(slicer): strip zero-valued filament-index sentinels, and sanitise the preview slice too (issue #3030)

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Bambu Studio writes 0 into wall_filament, sparse_infill_filament and
    solid_infill_filament to mean "use whichever filament the object is set
    to". Bambu Studio and OrcaSlicer 2.4 define these min 0 and accept it;
    OrcaSlicer 2.3 and earlier used the 1-based scheme (min 1, default 1)
    and reject it with "0 not in range [1.000000,...]". Sidecar images are
    version-tagged, so an install can be pinned to one of those builds.

    Same shape as the -1 inherit markers from #1201 with a different marker,
    so the allowlist becomes a key-to-marker map rather than one global
    constant. The buckets must not bleed: a -1 on a filament index is a real
    value, and a 0 on a raft field is a setting the user chose.

    The key is removed rather than rewritten, which is what makes it safe on
    every build. The CLI then uses its own default: 0 where 0 was legal
    (unchanged), 1 on the older builds, which is what "the active filament"
    means under that scheme.

    The preview slice never ran the sanitiser at all, so a file that sliced
    fine could still fail its automatic plate preview and fall back to the
    painted-face heuristic. It matters more there than in a real slice: the
    preview runs on the file's own embedded settings, so there is no
    --load-settings pass that could supply a replacement for a field the
    range validator has already rejected. That also explains the reported
    "same error on a later attempt of an unchanged file" without any second
    copy of the keys -- the validator that emits it reads the merged global
    config, which per-object model_settings.config overrides never reach.

    The sanitiser moves to utils/threemf_tools so the service can use it
    without importing a route module, and both preview callers pick it up
    from one place. Drops _strip_3mf_embedded_settings and its constant,
    which have had no callers since the strip-everything experiment was
    reverted.
This commit is contained in:
maziggy
2026-09-20 13:30:11 +02:00
parent f3dddf3f5b 9a837d19a1
commit ad09406672
5 changed files with 392 additions and 169 deletions
Download Patch File Download Diff File Expand all files Collapse all files
backend/app/api/routes/library.py
+9 -143
View File
@@ -94,6 +94,7 @@ from backend.app.utils.threemf_tools import (
extract_embedded_presets_from_3mf,
extract_nozzle_mapping_from_3mf,
extract_project_filaments_from_3mf,
sanitize_project_settings_sentinels,
select_plate_gcode_name,
supports_enabled_in_config,
)
@@ -3492,142 +3493,6 @@ async def get_library_file_filament_requirements(
}
_STRIPPABLE_3MF_CONFIGS = frozenset(
{
# Settings dump used by --load-settings validation; the CLI tries to
# match its sentinel values (`prime_tower_brim_width: -1`, empty
# arrays) against the supplied profile and rejects out-of-range.
"Metadata/project_settings.config",
# Per-object settings overrides referencing the source plate's
# filament IDs / printer IDs. When the user picks a different
# printer / filament triplet, the IDs no longer resolve and the
# CLI exits non-zero on input validation.
"Metadata/model_settings.config",
# Slicer-version + plate-config + filament-mapping snapshot from
# the original slice. Includes the original printer model and
# filament references; mismatches against `--load-settings`
# consistently surfaced as `Slicer CLI failed (500)` for every
# 3MF in production. Removing it lets the CLI build a fresh slice
# plan from the supplied profile triplet.
"Metadata/slice_info.config",
# Multi-part / split-mesh metadata referencing object IDs from the
# original slice. Strip for the same reason — preserves the geometry
# in `3D/3dmodel.model` while dropping the orphan references.
"Metadata/cut_information.xml",
}
)
def _strip_3mf_embedded_settings(zip_bytes: bytes) -> bytes:
"""Remove embedded slicer-config metadata from a 3MF.
Bambuddy supplies the slicer profile triplet via the sidecar's
``--load-settings`` path; the 3MF's embedded settings would otherwise be
validated by the CLI first and can fail with sentinel-value range
checks (`prime_tower_brim_width: -1 not in range`, etc.) regardless of
what we pass via ``--load-settings``. Stripping the embedded configs
forces the CLI to use the supplied profiles only. Geometry
(``3D/3dmodel.model``), thumbnails, color, and multi-part data inside
the 3MF are preserved.
The set of strippable filenames is centralised in
``_STRIPPABLE_3MF_CONFIGS`` — see that constant for the per-file
rationale. Project-settings alone wasn't enough: real-world Bambu
Studio 3MFs cross-reference printer / filament IDs from the other
metadata configs, and any single leftover triggered the validation
failure that made every profile-driven slice fall back to embedded
settings.
"""
from io import BytesIO
src = BytesIO(zip_bytes)
dst = BytesIO()
with zipfile.ZipFile(src, "r") as zin, zipfile.ZipFile(dst, "w", zipfile.ZIP_DEFLATED) as zout:
for item in zin.infolist():
if item.filename in _STRIPPABLE_3MF_CONFIGS:
continue
zout.writestr(item, zin.read(item.filename))
return dst.getvalue()
# Keys in ``Metadata/project_settings.config`` that BambuStudio writes ``"-1"``
# to when the user wants the value inherited from the parent process preset.
# The CLI's ``StaticPrintConfig`` validator runs against the embedded settings
# *before* ``--load-settings`` overrides apply, so a sentinel ``"-1"`` trips
# the field's lower-bound range check and the CLI exits non-zero before our
# profile triplet is ever consulted (#1201 — MakerWorld P2S models).
#
# Allowlisted (rather than "strip every '-1' value") because some fields
# legitimately accept negative numbers (z_offset, translation values, etc.)
# and a blanket strip would silently corrupt those.
#
# Add new entries here as more reports surface — the slicer's error message
# names the offending field directly (`<field>: -1 not in range [...]`).
_PROJECT_SETTINGS_SENTINEL_KEYS = frozenset(
{
# Reported in #1201 (MakerWorld P2S 3MFs).
"raft_first_layer_expansion",
"tree_support_wall_count",
# Cited in the strip-experiment comment block above as a known sentinel
# case from earlier reports.
"prime_tower_brim_width",
}
)
def _sanitize_project_settings_sentinels(zip_bytes: bytes) -> bytes:
"""Strip ``"-1"`` inherit-from-parent sentinels from the 3MF's
``Metadata/project_settings.config`` so the slicer CLI's range validator
accepts the file (#1201).
Removes only allowlisted keys (see ``_PROJECT_SETTINGS_SENTINEL_KEYS``)
when their value is exactly ``"-1"``. The rest of the config — and every
other entry in the zip — is preserved byte-for-byte. Unlike the earlier
full-strip experiment (see ``_strip_3mf_embedded_settings`` and the
cautionary comment in ``_run_slicer_with_fallback``) this leaves
``StaticPrintConfig`` initialisation intact: the file is still present,
still parses, and the slicer falls back to the supplied
``--load-settings`` value for the removed key.
Returns the original bytes unchanged when no sanitisation is needed
(input isn't a valid zip, no ``project_settings.config``, no allowlisted
sentinels present, or any other parse failure) so the caller can pass
the result on without further checks.
"""
from io import BytesIO
try:
with zipfile.ZipFile(BytesIO(zip_bytes), "r") as zin:
if "Metadata/project_settings.config" not in zin.namelist():
return zip_bytes
try:
config = json.loads(zin.read("Metadata/project_settings.config").decode("utf-8"))
except (json.JSONDecodeError, UnicodeDecodeError):
return zip_bytes
if not isinstance(config, dict):
return zip_bytes
removed = [key for key in _PROJECT_SETTINGS_SENTINEL_KEYS if config.get(key) == "-1"]
if not removed:
return zip_bytes
for key in removed:
config.pop(key, None)
patched = json.dumps(config)
logger.info(
"3MF sanitiser: removed sentinel '-1' for keys %s — slicer will use --load-settings defaults",
sorted(removed),
)
dst = BytesIO()
with zipfile.ZipFile(dst, "w", zipfile.ZIP_DEFLATED) as zout:
for item in zin.infolist():
if item.filename == "Metadata/project_settings.config":
zout.writestr(item, patched)
else:
zout.writestr(item, zin.read(item.filename))
return dst.getvalue()
except (zipfile.BadZipFile, OSError):
return zip_bytes
def _patch_process_bed_type(process_json: str, bed_type: str) -> str:
"""Overwrite ``curr_bed_type`` in a process-profile JSON before forwarding
to the slicer sidecar.
@@ -4022,13 +3887,14 @@ async def _run_slicer_with_fallback(
is_3mf = model_filename.lower().endswith(".3mf")
primary_bytes = model_bytes
if is_3mf:
# Strip "-1" inherit-from-parent sentinels from
# Metadata/project_settings.config so the CLI's StaticPrintConfig
# range validator accepts the file (#1201). Surgical — keeps the
# config present, just removes the offending keys; the supplied
# --load-settings (and the fallback's embedded values for keys we
# didn't touch) still drive the slice.
primary_bytes = _sanitize_project_settings_sentinels(primary_bytes)
# Strip inherit/unset sentinels from Metadata/project_settings.config
# so the CLI's StaticPrintConfig range validator accepts the file
# (#1201, #3030). Surgical — keeps the config present, just removes
# the offending keys; the supplied --load-settings (and the fallback's
# embedded values for keys we didn't touch) still drive the slice.
# The preview-slice path applies the same sanitiser in
# ``slice_preview.get_preview_filaments``.
primary_bytes = sanitize_project_settings_sentinels(primary_bytes)
# #2622: the process settings the file's designer moved off the stock
# preset. Read once — the support patch below needs to know which of
backend/app/services/slice_preview.py
+27 -8
View File
@@ -14,10 +14,13 @@ we don't need to thread the user's profile triplet through here. That choice
also protects the numbers — overriding the process preset drops the project's
own support configuration, which loses whole slots from the answer.
The one thing that can defeat those embedded settings is a custom G-code
template written by a Studio newer than the sidecar, which fails to parse
before any slice_info exists. That case gets one retry with the offending
template blanked; see ``_blank_custom_gcode``.
Two things can defeat those embedded settings. A custom G-code template
written by a Studio newer than the sidecar fails to parse before any
slice_info exists; that case gets one retry with the offending template
blanked, see ``_blank_custom_gcode``. And Bambu Studio writes inherit/unset
markers into ``project_settings.config`` that some slicer builds' range
validator rejects outright, so the same sanitiser the real slice runs is
applied here too, see ``sanitize_project_settings_sentinels``.
Results are cached by ``(kind, source_id, plate_id, content_hash)`` so
repeat opens on the same plate are instant. LRU eviction keeps the cache
@@ -42,6 +45,7 @@ from backend.app.services.slicer_api import (
SlicerApiError,
SlicerApiService,
)
from backend.app.utils.threemf_tools import sanitize_project_settings_sentinels
logger = logging.getLogger(__name__)
@@ -203,13 +207,17 @@ async def get_preview_filaments(
Uses the file's embedded settings (``slice_without_profiles``) since the
slot mapping is a model property, independent of any user-picked profile
triplet. A slice killed by an unparsable custom G-code template is retried
once with that template blanked, still on the file's own settings.
triplet. Those settings are sentinel-sanitised first (#1201, #3030). A
slice killed by an unparsable custom G-code template is retried once with
that template blanked, still on the file's own settings.
Returns ``None`` when the preview slice fails — the caller should fall
back to whatever heuristic it has (typically the project_filaments +
painted-face approach in ``threemf_tools``).
"""
# Hash the file as it was given to us, not as it is sent: the key
# identifies the source file, and sanitising is deterministic, so folding
# it in would only make two names for one thing.
h = _content_hash(file_bytes)
key: _PreviewCacheKey = (kind, source_id, plate_id, h)
cached = _preview_cache.get(key)
@@ -231,6 +239,17 @@ async def get_preview_filaments(
# while the slicer is visibly working.
svc_kwargs = {} if timeout_seconds is None else {"timeout_seconds": timeout_seconds}
# Same sanitiser the real slice runs (#1201, #3030). It matters more
# here, not less: this path slices on the file's own embedded
# settings, so there is no --load-settings pass that could supply a
# replacement for a field the CLI's range validator has already
# rejected. Without it a MakerWorld 3MF carrying Bambu's inherit
# markers fails before producing any slice_info, and the modal falls
# back to its painted-face heuristic for a file the slicer could have
# answered exactly. Applied before the G-code retry below so that
# retry inherits it rather than reintroducing the markers.
slice_bytes = sanitize_project_settings_sentinels(file_bytes)
async def _slice(model_bytes: bytes):
async with SlicerApiService(base_url=api_url, **svc_kwargs) as svc:
return await svc.slice_without_profiles(
@@ -242,7 +261,7 @@ async def get_preview_filaments(
)
try:
result = await _slice(file_bytes)
result = await _slice(slice_bytes)
except SlicerApiError as e:
# One retry, and only for a custom-G-code template the sidecar
# cannot parse — a file from a Studio newer than the sidecar. The
@@ -259,7 +278,7 @@ async def get_preview_filaments(
retry_bytes = None
option = _unparsable_gcode_option(str(e))
if option is not None:
retry_bytes = _blank_custom_gcode(file_bytes, option)
retry_bytes = _blank_custom_gcode(slice_bytes, option)
if retry_bytes is None:
logger.warning(
"Preview slice failed for %s/%s plate %s: %s",
backend/app/utils/threemf_tools.py
+122
View File
@@ -1767,3 +1767,125 @@ def extract_plate_extruder_set_from_3mf(zf: zipfile.ZipFile, plate_id: int) -> s
used.update(_scan_paint(path))
break
return used
# Keys in ``Metadata/project_settings.config`` that Bambu Studio writes an
# "inherit / unset" marker into, mapped to the marker it uses for that key.
# The slicer CLI's ``StaticPrintConfig`` validator runs against the embedded
# settings *before* ``--load-settings`` overrides apply, so a marker the CLI's
# own range check rejects makes it exit non-zero before our profile triplet is
# ever consulted.
#
# There are two markers because there are two conventions, and which one a
# given CLI rejects depends on the build:
#
# "-1" -- inherit from the parent process preset (#1201, MakerWorld P2S
# 3MFs). ``raft_first_layer_expansion`` and ``tree_support_wall_count`` are
# min 0 in every OrcaSlicer to date, so those still fail on the current
# sidecar; ``prime_tower_brim_width`` gained min -1 in Orca 2.4.2 and now
# passes there, but not on older builds.
#
# "0" -- "use the active object/part filament", the default Bambu Studio
# writes for the three feature-filament indices (#3030). Bambu Studio and
# OrcaSlicer 2.4.0+ both define these min 0, so 0 is legal there; OrcaSlicer
# 2.3.x and earlier still used the 1-based scheme (min 1, default 1) and
# reject it with ``0 not in range [1.000000,...]``. Sidecar images are
# version-tagged, so an install can be pinned to one of those.
#
# Removing the key rather than rewriting it is what makes this safe on every
# build: the CLI then falls back to its own compiled default, which is 0 on
# the builds where 0 was legal (so nothing changes) and 1 on the older ones,
# which is what "the active filament" means under that scheme.
#
# Allowlisted (rather than "strip every marker-shaped value") because some
# fields legitimately take the marker value -- z_offset, translations, and any
# feature index a user really did set to a first filament -- and a blanket
# strip would silently corrupt those.
#
# Add new entries as reports surface: the slicer names the offending field
# directly, e.g. ``<field>: <value> not in range [...]``.
PROJECT_SETTINGS_SENTINELS: dict[str, str] = {
# Reported in #1201 (MakerWorld P2S 3MFs).
"raft_first_layer_expansion": "-1",
"tree_support_wall_count": "-1",
# Known sentinel case from earlier reports, cited in #1201.
"prime_tower_brim_width": "-1",
# Reported in #3030 (MakerWorld 3MF, OrcaSlicer sidecar).
"wall_filament": "0",
"sparse_infill_filament": "0",
"solid_infill_filament": "0",
}
PROJECT_SETTINGS_PATH = "Metadata/project_settings.config"
def _is_sentinel(value: object, sentinel: str) -> bool:
"""Does ``value`` carry ``sentinel``, whether stored as text or a number?
Bambu Studio writes every ``project_settings.config`` value as a string,
but a 3MF that has been round-tripped through another tool can carry the
same field as a JSON number. ``bool`` is excluded explicitly: it is an
``int`` subclass in Python, and ``str(False)`` would otherwise never match
anyway -- the exclusion is there so a future numeric sentinel like ``0``
cannot be matched by ``False``.
"""
if isinstance(value, bool):
return False
if isinstance(value, (str, int)):
return str(value) == sentinel
return False
def sanitize_project_settings_sentinels(zip_bytes: bytes) -> bytes:
"""Strip inherit/unset sentinels from a 3MF's ``project_settings.config``
so the slicer CLI's range validator accepts the file (#1201, #3030).
Removes only allowlisted keys (see ``PROJECT_SETTINGS_SENTINELS``) and only
when the value is exactly that key's sentinel. The rest of the config --
and every other entry in the zip -- is preserved byte-for-byte. Unlike a
whole-file strip this leaves ``StaticPrintConfig`` initialisation intact:
the file is still present, still parses, and the slicer falls back to the
supplied ``--load-settings`` value, or to its own default, for the removed
key.
Returns the original bytes unchanged when no sanitisation is needed (input
isn't a valid zip, no ``project_settings.config``, no allowlisted sentinels
present, or any other parse failure) so the caller can pass the result on
without further checks.
"""
from io import BytesIO
try:
with zipfile.ZipFile(BytesIO(zip_bytes), "r") as zin:
if PROJECT_SETTINGS_PATH not in zin.namelist():
return zip_bytes
try:
config = json.loads(zin.read(PROJECT_SETTINGS_PATH).decode("utf-8"))
except (json.JSONDecodeError, UnicodeDecodeError):
return zip_bytes
if not isinstance(config, dict):
return zip_bytes
removed = {
key: sentinel
for key, sentinel in PROJECT_SETTINGS_SENTINELS.items()
if _is_sentinel(config.get(key), sentinel)
}
if not removed:
return zip_bytes
for key in removed:
config.pop(key, None)
patched = json.dumps(config)
logger.info(
"3MF sanitiser: removed inherit sentinels %s - slicer will use its defaults for those keys",
sorted(f"{key}={sentinel}" for key, sentinel in removed.items()),
)
dst = BytesIO()
with zipfile.ZipFile(dst, "w", zipfile.ZIP_DEFLATED) as zout:
for item in zin.infolist():
if item.filename == PROJECT_SETTINGS_PATH:
zout.writestr(item, patched)
else:
zout.writestr(item, zin.read(item.filename))
return dst.getvalue()
except (zipfile.BadZipFile, OSError):
return zip_bytes
backend/tests/unit/services/test_slice_preview.py
+136
View File
@@ -495,3 +495,139 @@ class TestPreviewRetriesUnparsableGcode:
assert len(stub.calls) == 2
# A failed retry must not be cached — the sidecar may be upgraded.
assert not slice_preview._preview_cache
class _RecordingService:
"""Succeeds every slice, recording the bytes it was handed."""
def __init__(self, response_bytes: bytes) -> None:
self.response_bytes = response_bytes
self.calls: list[bytes] = []
async def __aenter__(self):
return self
async def __aexit__(self, *exc):
return False
async def slice_without_profiles(self, **kw):
self.calls.append(kw["model_bytes"])
return SliceResult(
content=self.response_bytes,
print_time_seconds=0,
filament_used_g=0.0,
filament_used_mm=0.0,
)
class TestPreviewSanitisesSentinels:
"""The preview slices on the file's own embedded settings, so there is no
``--load-settings`` pass to supply a replacement for a field the CLI's
range validator has already rejected. Until #3030 this path handed the
sidecar raw bytes, so a MakerWorld 3MF carrying Bambu's inherit markers
failed before producing any slice_info and the modal fell back to its
painted-face heuristic for a file the slicer could have answered exactly.
"""
@pytest.mark.asyncio
async def test_the_slicer_is_handed_sanitised_bytes(self):
original = _make_project_3mf(
{
"wall_filament": "0",
"raft_first_layer_expansion": "-1",
"layer_height": "0.2",
}
)
body = _make_sliced_3mf(plate_id=1, filaments=[{"id": "1", "type": "PLA", "color": "#000"}])
stub = _RecordingService(body)
with patch.object(slice_preview, "SlicerApiService", lambda **kw: stub):
result = await get_preview_filaments(
kind="library_file",
source_id=1,
plate_id=1,
file_bytes=original,
file_name="x.3mf",
api_url="http://sidecar",
)
assert result is not None
sent = _settings_of(stub.calls[0])
assert "wall_filament" not in sent
assert "raft_first_layer_expansion" not in sent
# Everything the user actually configured still reaches the slicer.
assert sent["layer_height"] == "0.2"
@pytest.mark.asyncio
async def test_a_file_without_sentinels_is_forwarded_untouched(self):
original = _make_project_3mf({"layer_height": "0.2", "wall_filament": "2"})
body = _make_sliced_3mf(plate_id=1, filaments=[{"id": "1", "type": "PLA", "color": "#000"}])
stub = _RecordingService(body)
with patch.object(slice_preview, "SlicerApiService", lambda **kw: stub):
await get_preview_filaments(
kind="library_file",
source_id=1,
plate_id=1,
file_bytes=original,
file_name="x.3mf",
api_url="http://sidecar",
)
# Not merely equal: the sanitiser returns the input object when it has
# nothing to do, so the common case never pays for a zip rebuild.
assert stub.calls[0] is original
@pytest.mark.asyncio
async def test_the_gcode_retry_keeps_the_sanitisation(self):
# Both faults at once. The retry derives from the sanitised bytes, so
# it must not reintroduce the sentinel while blanking the template --
# otherwise the retry trades one CLI rejection for the other.
original = _make_project_3mf(
{
"time_lapse_gcode": "{if timelapse_inline_photo}",
"wall_filament": "0",
"layer_height": "0.2",
}
)
body = _make_sliced_3mf(plate_id=1, filaments=[{"id": "1", "type": "PLA", "color": "#000"}])
stub = _FailThenSucceedService(SlicerApiServerError(_TIMELAPSE_PARSE_ERROR), body)
with patch.object(slice_preview, "SlicerApiService", lambda **kw: stub):
result = await get_preview_filaments(
kind="library_file",
source_id=1,
plate_id=1,
file_bytes=original,
file_name="x.3mf",
api_url="http://sidecar",
)
assert result is not None
assert len(stub.calls) == 2
for sent in stub.calls:
assert "wall_filament" not in _settings_of(sent)
assert _settings_of(stub.calls[1])["time_lapse_gcode"] == ""
assert _settings_of(stub.calls[1])["layer_height"] == "0.2"
@pytest.mark.asyncio
async def test_the_cache_key_still_follows_the_source_file(self):
# Sanitising is deterministic, so the key stays the hash of what the
# caller read off disk -- a second open of the same file is a hit, not
# a second 30-second slice.
original = _make_project_3mf({"wall_filament": "0"})
body = _make_sliced_3mf(plate_id=1, filaments=[{"id": "1", "type": "PLA", "color": "#000"}])
stub = _RecordingService(body)
with patch.object(slice_preview, "SlicerApiService", lambda **kw: stub):
first = await get_preview_filaments(
kind="library_file",
source_id=1,
plate_id=1,
file_bytes=original,
file_name="x.3mf",
api_url="http://sidecar",
)
second = await get_preview_filaments(
kind="library_file",
source_id=1,
plate_id=1,
file_bytes=original,
file_name="x.3mf",
api_url="http://sidecar",
)
assert second == first
assert len(stub.calls) == 1
backend/tests/unit/test_project_settings_sentinel_sanitiser.py
+98 -18
View File
@@ -1,4 +1,4 @@
"""Unit tests for ``_sanitize_project_settings_sentinels`` (#1201).
"""Unit tests for ``sanitize_project_settings_sentinels`` (#1201, #3030).
MakerWorld 3MFs sliced for the P2S (and potentially other Bambu printers)
ship ``Metadata/project_settings.config`` entries with ``"-1"`` values on
@@ -22,6 +22,21 @@ re-zip. The slicer then falls back to the supplied ``--load-settings``
default for the removed keys, while every other entry in the zip stays
byte-identical.
#3030 added a second sentinel value. ``wall_filament``,
``sparse_infill_filament`` and ``solid_infill_filament`` are filament indices
that Bambu Studio writes as ``"0"`` meaning "use the active object/part
filament". Bambu Studio and OrcaSlicer 2.4.0+ define these ``min 0``, so the
value is legal there; OrcaSlicer 2.3.x and earlier used the 1-based scheme
(``min 1``, default ``1``) and answer::
wall_filament: 0 not in range [1.000000,...]
Sidecar images are version-tagged, so an install can be pinned to one of
those builds. So the allowlist is a key -> sentinel mapping now rather than
one global constant, and the two buckets must not bleed into each other: a
``"-1"`` on a filament index is not a sentinel, and a ``"0"`` on a raft field
is a value the user chose.
Pinning the contract here rather than via the slicer integration tests
because the fix is purely about the bytes we hand to the sidecar — no
slicer mock needed.
@@ -33,9 +48,9 @@ import zipfile
import pytest
from backend.app.api.routes.library import (
_PROJECT_SETTINGS_SENTINEL_KEYS,
_sanitize_project_settings_sentinels,
from backend.app.utils.threemf_tools import (
PROJECT_SETTINGS_SENTINELS,
sanitize_project_settings_sentinels,
)
@@ -65,10 +80,10 @@ def _zip_namelist(zip_bytes: bytes) -> list[str]:
class TestRemovesSentinelValues:
@pytest.mark.parametrize("key", sorted(_PROJECT_SETTINGS_SENTINEL_KEYS))
def test_removes_each_allowlisted_key_when_value_is_minus_one(self, key):
original = _make_3mf(settings={key: "-1", "layer_height": "0.2"})
sanitised = _sanitize_project_settings_sentinels(original)
@pytest.mark.parametrize(("key", "sentinel"), sorted(PROJECT_SETTINGS_SENTINELS.items()))
def test_removes_each_allowlisted_key_at_its_own_sentinel(self, key, sentinel):
original = _make_3mf(settings={key: sentinel, "layer_height": "0.2"})
sanitised = sanitize_project_settings_sentinels(original)
cfg = _read_settings(sanitised)
assert key not in cfg, f"Sentinel key {key!r} should have been removed"
@@ -85,7 +100,7 @@ class TestRemovesSentinelValues:
"layer_height": "0.2",
}
)
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
cfg = _read_settings(sanitised)
assert "raft_first_layer_expansion" not in cfg
@@ -99,7 +114,7 @@ class TestPreservesUnaffectedValues:
# A user who deliberately configured raft_first_layer_expansion=0 must
# see that 0 forwarded to the slicer — only literal "-1" gets stripped.
original = _make_3mf(settings={"raft_first_layer_expansion": "0"})
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
assert _read_settings(sanitised)["raft_first_layer_expansion"] == "0"
def test_does_not_touch_non_allowlisted_keys_with_minus_one(self):
@@ -107,7 +122,7 @@ class TestPreservesUnaffectedValues:
# Some Bambu fields legitimately allow negative values (z_offset,
# translation, etc.) and a blanket "-1" strip would corrupt those.
original = _make_3mf(settings={"z_offset": "-1", "layer_height": "0.2"})
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
cfg = _read_settings(sanitised)
assert cfg["z_offset"] == "-1"
@@ -117,7 +132,7 @@ class TestPreservesUnaffectedValues:
# If nothing needs sanitising, return the input identity-equal so
# the caller's downstream comparisons / hashes don't churn.
original = _make_3mf(settings={"layer_height": "0.2", "z_offset": "0"})
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
assert sanitised is original
def test_does_not_strip_array_value_even_if_includes_minus_one(self):
@@ -128,7 +143,7 @@ class TestPreservesUnaffectedValues:
# sentinel and removed wholesale. If a future report shows the CLI
# rejects array-form sentinels, expand this then.
original = _make_3mf(settings={"raft_first_layer_expansion": ["-1", "0"]})
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
cfg = _read_settings(sanitised)
assert cfg["raft_first_layer_expansion"] == ["-1", "0"]
@@ -143,7 +158,7 @@ class TestZipPreservation:
"Metadata/_rels/model_settings.rels": "<rels/>",
},
)
sanitised = _sanitize_project_settings_sentinels(original)
sanitised = sanitize_project_settings_sentinels(original)
assert sanitised is not original
names = _zip_namelist(sanitised)
@@ -171,12 +186,12 @@ class TestDefensiveFallbacks:
# routing decides whether 3MF sanitisation runs anyway, but
# defending here means a misrouted call can't corrupt the bytes.
garbage = b"not a zip file"
assert _sanitize_project_settings_sentinels(garbage) is garbage
assert sanitize_project_settings_sentinels(garbage) is garbage
def test_returns_original_when_settings_config_absent(self):
# 3MF without an embedded project_settings.config — nothing to do.
original = _make_3mf(settings=None)
assert _sanitize_project_settings_sentinels(original) is original
assert sanitize_project_settings_sentinels(original) is original
def test_returns_original_on_malformed_json(self):
# Settings file present but not valid JSON. We don't risk rebuilding
@@ -187,7 +202,7 @@ class TestDefensiveFallbacks:
zf.writestr("3D/3dmodel.model", "<model/>")
zf.writestr("Metadata/project_settings.config", "{not valid json")
original = buf.getvalue()
assert _sanitize_project_settings_sentinels(original) is original
assert sanitize_project_settings_sentinels(original) is original
def test_returns_original_when_settings_root_is_not_a_dict(self):
# Real-world configs are objects, but defend against an array root
@@ -198,4 +213,69 @@ class TestDefensiveFallbacks:
zf.writestr("3D/3dmodel.model", "<model/>")
zf.writestr("Metadata/project_settings.config", "[]")
original = buf.getvalue()
assert _sanitize_project_settings_sentinels(original) is original
assert sanitize_project_settings_sentinels(original) is original
class TestTheTwoSentinelBucketsDoNotBleed:
"""Each key has exactly one sentinel, and the other bucket's value is a
real setting on it. Getting this wrong in either direction is worse than
the bug: strip a filament index that says ``-1`` and the slice loses a
value nothing will put back; strip a raft field that says ``0`` and a
user who deliberately turned the raft expansion off gets the preset's
default instead."""
@pytest.mark.parametrize("key", ["wall_filament", "sparse_infill_filament", "solid_infill_filament"])
def test_a_filament_index_of_minus_one_is_left_alone(self, key):
original = _make_3mf(settings={key: "-1"})
assert sanitize_project_settings_sentinels(original) is original
@pytest.mark.parametrize("key", ["raft_first_layer_expansion", "tree_support_wall_count", "prime_tower_brim_width"])
def test_a_zero_on_a_minus_one_key_is_left_alone(self, key):
original = _make_3mf(settings={key: "0"})
assert sanitize_project_settings_sentinels(original) is original
def test_a_mixed_config_removes_exactly_the_sentinels(self):
original = _make_3mf(
settings={
# sentinels, both buckets
"raft_first_layer_expansion": "-1",
"wall_filament": "0",
# same keys' non-sentinel values, crossed over
"tree_support_wall_count": "0",
"sparse_infill_filament": "-1",
# an explicit filament pick
"solid_infill_filament": "2",
"layer_height": "0.2",
}
)
cfg = _read_settings(sanitize_project_settings_sentinels(original))
assert "raft_first_layer_expansion" not in cfg
assert "wall_filament" not in cfg
assert cfg["tree_support_wall_count"] == "0"
assert cfg["sparse_infill_filament"] == "-1"
assert cfg["solid_infill_filament"] == "2"
assert cfg["layer_height"] == "0.2"
class TestNumericValuesAreRecognised:
"""Bambu Studio writes every value as a string, but a 3MF round-tripped
through another tool can carry the same field as a JSON number. The
slicer's validator reads the deserialised int either way, so the
sanitiser has to as well."""
def test_an_integer_sentinel_is_removed(self):
original = _make_3mf(settings={"wall_filament": 0, "layer_height": "0.2"})
cfg = _read_settings(sanitize_project_settings_sentinels(original))
assert "wall_filament" not in cfg
assert cfg["layer_height"] == "0.2"
def test_an_integer_non_sentinel_survives(self):
original = _make_3mf(settings={"wall_filament": 2})
assert sanitize_project_settings_sentinels(original) is original
def test_false_is_not_a_zero_sentinel(self):
# bool is an int subclass in Python. A config that stores a flag as
# JSON ``false`` under one of these names must not be mistaken for
# the numeric 0 sentinel.
original = _make_3mf(settings={"wall_filament": False})
assert sanitize_project_settings_sentinels(original) is original