text-extract

F∆I module — extract plain text from PDF and DOCX documents.

Capability

Field	Value
Capability	text.extract@0.1.0
Inputs	document: bytes (PDF or DOCX)
Outputs	extracted: json (ExtractedDocument)
Permissions	none — pure in-WASM, no filesystem, no network
Status (in store index)	alpha

Output schema

{
  "engine": "pdf-extract",
  "engine_version": "0.7",
  "pages": [
    { "number": 1, "text": "..." }
  ]
}

confidence and bbox per page are reserved for a future service-mode variant (host-services-backed pdfium/mupdf engine). v0.1.0 does not populate them; the schema accepts them as optional so that v0.2.0 can extend without an interface break.

Build

cargo build --release --target wasm32-wasip2
# Artifact: target/wasm32-wasip2/release/text_extract.wasm

The build depends on a sibling checkout of fai/module-sdk:

~/fai/
├── module_sdk/                 # cloned from fai/module-sdk
└── fai_modules/
    └── text-extract/           # this repo

This is a temporary path-based dependency. Once chain-module-sdk is published to a registry or a stable git tag, this module's Cargo.toml will switch over. The Forgejo CI workflow checks out the SDK repo into a sibling directory before building.

Test

cargo test                       # 9 tests: 6 unit + 3 integration
cargo test --release             # same, optimized

The DOCX path is covered end-to-end by an integration test that builds a minimal valid DOCX in memory and feeds it through invoke. The PDF path is covered by unit tests on the page splitter; full PDF coverage will land once the platform's hub loads this wasm component as part of its store-install integration test.

Limitations of v0.1.0

• Layout-naive PDF parsing. Multi-column layouts and tables may produce reordered text. Single-column documents work reliably.
• DOCX text only. Tables, footnotes, headers/footers and embedded objects are not yet extracted. Plain paragraph text with run-level concatenation is the v0.1.0 surface.
• No OCR. Image-only PDFs return empty text per page. An OCR variant will arrive as a separate module (text.ocr@x.y.z) once the host-services infrastructure for tesseract is in place.

License

Apache-2.0. See LICENSE.

Author: Dr. Stefan Flemming, Flemming.AI chain@flemming.ai Repository: https://git.flemming.ws/fai-modules/text-extract