Crate docling_core 

Core data model for docling.rs.

This crate is the Rust counterpart of the docling-core Python package: it owns the unified DoclingDocument representation that every backend produces and every serializer consumes. Keeping it dependency-light and separate from the conversion logic mirrors the Python split between docling-core (the schema) and docling (the converters).

Phase 0 models a simplified, linear node tree that is enough to round-trip through Markdown. The faithful, $ref-based schema that matches docling-core’s JSON wire format lands in Phase 1 (see MIGRATION.md).

Modules

base64

Minimal standard-alphabet Base64 codec (RFC 4648): encode for embedding image bytes as data: URIs, decode for reading them back out — avoids a dependency for the two things we need.

Structs

DoclingDocument

The unified, format-agnostic document produced by every backend.

FieldItem

One entry of a Node::FieldRegion: a marker/key/value triple, any of which may be absent. Mirrors docling’s field_item with its marker / field_key / field_value child texts.

InlineRun

One styled segment of a Node::InlineGroup — the docling.rs analogue of a TextItem inside an InlineGroup, carrying the ancestor formatting docling tracks. text is already whitespace-normalized/trimmed (one segment per source text node). A hyperlink is intentionally not stored: DocLang drops the target inside inline scope, keeping only the anchor text.

MarkdownStreamer

Incremental Markdown serializer: feed finalized, in-document-order batches of Nodes and receive Markdown chunks whose concatenation is byte-identical to [to_markdown_images] over the same nodes. This is the streaming counterpart of the buffered serializer — used to emit a document’s Markdown in chunks (e.g. page by page, as the parallel PDF pipeline finishes pages) instead of building the whole string up front.

PictureImage

An extracted picture’s raw encoded bytes plus its mimetype and pixel size — the docling.rs analogue of docling-core’s ImageRef.

Table

A simple row-major table. rows[0] is the header row.

Enums

DocItemLabel

Semantic role of a document item, mirroring docling-core’s DocItemLabel.

ImageMode

How pictures are rendered (mirrors docling-core’s ImageRefMode).

Node

A single piece of document content.

Script

Vertical text position of an InlineRun — docling’s Script.

Functions

inline_paragraph_node

Build the Node for a paragraph of inline content from its structured runs and Markdown text, applying docling’s InlineGroup boundary:

inline_runs_from_markdown

Parse a docling-legacy Markdown string into structured InlineRuns for a Node::InlineGroup. Handles the marker set docling emits — ***, **, *, ~~, `, [t](u) — recursively so nested markers combine formatting, and splits plain text on newlines (docling’s <br> / text-node boundaries become separate runs). Underline and sub/superscript have no Markdown representation and therefore never appear via this path.