pdftract/crates/pdftract-core
jedarden 85a502c346 fix(pdftract-31bum): implement smarter backpressure for OutOfOrderBuffer
The OutOfOrderBuffer had a deadlock issue where:
1. Buffer fills with 8 pages from workers
2. Next expected page (e.g., page 0) is missing
3. All workers block trying to push more pages
4. Deadlock because no one can push page 0

Fix: Implement smarter backpressure that:
- Blocks when buffer is full AND next expected page is missing
- Allows push if we're pushing the missing next expected page
- Allows push if next expected page is already in buffer

Also add pop_next_in_order_blocking() for multi-threaded scenarios.

Acceptance criteria:
- Unit test: push pages 3,1,4,1,5,9,2,6 -> pop in 0..=9 order PASS
- Backpressure test: 9th push blocks until page 0 arrives PASS
- Concurrency stress test: 8 workers + 1 consumer, 1000 pages PASS
- finish() test: producer finished, heap drained -> pop returns None PASS

Closes: pdftract-31bum

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-26 17:15:06 -04:00
..
benches fix: resolve compilation errors across codebase 2026-05-25 08:38:04 -04:00
build feat(pdftract-9wevc): implement 20k English wordlist for readability scoring 2026-05-24 09:29:13 -04:00
examples feat(pdftract-3s2i): implement Phase 5.5.2 validation filter 2026-05-24 04:57:17 -04:00
proptest-regressions/parser/lexer feat(pdftract-1jjn): implement PDF numeric literal lexer with full edge case support 2026-05-23 23:17:04 -04:00
src fix(pdftract-31bum): implement smarter backpressure for OutOfOrderBuffer 2026-05-26 17:15:06 -04:00
tests test(pdftract-4w0v4): implement adversarial test corpus + integration harness 2026-05-25 14:30:24 -04:00
__test__.pdf feat(pdftract-15pz8): implement multi-process safe cache operations 2026-05-23 05:31:11 -04:00
build.rs fix: resolve compilation errors across codebase 2026-05-25 08:38:04 -04:00
Cargo.toml feat(pdftract-55ihl): implement Otsu global thresholding for OCR preprocessing 2026-05-25 12:41:17 -04:00
pdftract-core.cdx.json feat(pdftract-67tm8): implement MCP stdio transport with integration tests 2026-05-23 00:16:42 -04:00
README.md docs(pdftract-49f8): establish Cargo.lock policy and documentation 2026-05-20 18:13:14 -04:00

pdftract-core

The core Rust library for PDF text extraction. This crate provides the parsing, layout analysis, font encoding recovery, and text extraction primitives used by the CLI (pdftract-cli) and Python bindings (pdftract-py).

Cargo.lock Policy

This workspace checks in Cargo.lock at the repository root. This is unconventional for library crates—the Cargo Book historically suggested that only binary crates should check in lockfiles, allowing library consumers to resolve their own dependency versions.

pdftract departs from this convention for release reproducibility:

  1. SLSA Level 3 provenance requires that every milestone tag produces byte-identical artifacts across builds. Without a checked-in lockfile, two runs of cargo build on the same commit can resolve different transitive dependency versions, producing different binary hashes.

  2. Multi-output artifacts—this workspace produces Rust crates (pdftract-core, pdftract-cli), Python wheels (pdftract-py), and Docker images. All must be built from the same dependency tree.

  3. Supply-chain security—the lockfile pins checksums for all transitive dependencies, enabling cargo audit to detect yanked or compromised crates.

  4. Downstream consumers can still ignore the lockfile if needed. Cargo allows cargo build --frozen with a local lockfile override, or consumers can vendor the crate with their own dependency resolution.

The tradeoff—occasional merge conflicts when PRs update overlapping dependencies—is worth the guarantee of reproducible releases. See CONTRIBUTING.md for the lockfile-update workflow.

Modules

  • parser: PDF spec parsing (xref, trailer, object streams, indirect references)
  • font: Font encoding recovery, glyph name lookup, fingerprinting
  • layout: Page layout analysis, region segmentation, reading order
  • extract: Text extraction with provenance (bounding boxes, confidence scores)
  • ocr: Tesseract integration for raster pages

Usage

use pdftract_core::{extract_text, ExtractOptions};

let options = ExtractOptions::default();
let result = extract_text("document.pdf", &options)?;
println!("{}", result.text);