LDraw bridge and BOMs¶

Core translation uses neutral LDrawBomItem and LDrawColorInfo records and does not import pyldraw3. Install rebrickable[ldraw] for adapters built only on the public Model, BomRow, Colour, Parts, load_model, and BOM APIs.

Part resolution order is user override, cached API LDraw ID, exact normalized canonical ID, relationship candidates, then unresolved. Color resolution uses override, cached API ID, unique RGB plus transparency, unique normalized name plus transparency, then ambiguity/unresolved. Normalization changes slashes and case and removes only a trailing .dat; it preserves meaningful decoration suffixes.

from rebrickable import LDrawBomItem, RebrickableSession

items = (LDrawBomItem("3001.dat", 4, 2),)
async with await RebrickableSession.open() as session:
    report = await session.translate_bom(items)

No translation calls the API implicitly. enrich_part_mapping() and enrich_color_mapping() are explicit and require a RebrickableClient; confirmed crosswalks are serialized with catalog promotion and immediately become local search fields. Enrichment authoritatively replaces previously cached mappings for the same entity and system, so re-enriching repairs stale crosswalks; mappings whose canonical id vanishes from a new snapshot are dropped during refresh. YAML overrides are versioned, deterministic, and materialized into each snapshot. Part source_id values may be written with or without the .dat suffix — they are normalized on load — and color override identifiers must be integers.

Bom.from_csv() accepts Part,Color,Quantity with optional additional columns. Bom.from_rebrickable_csv() accepts Rebrickable part_num,color_id,quantity inventory/custom-list columns (plus their common aliases), and Bom.from_bricklink_xml() accepts BrickLink wanted-list XML and preserves the BrickLink part and color namespaces (Bom.from_rebrickable_xml() remains as an alias and also returns BrickLink-namespaced references). Pass a Path for file input; strings are always interpreted as inline content, and a single-line string ending in .csv/.xml raises with guidance instead of being parsed. Quantities must be positive. Duplicate rows are recorded before aggregation; normalization, diffs, validation, and Rebrickable custom-list CSV are stable.

Translation exports never replace original LDraw identifiers. They add resolved Rebrickable identifiers, source strategies, candidates, explanations, and the snapshot ID. JSON, RFC 4180 CSV, compact tables, and unresolved-only reports are available.