Add universal document decoder with multi-format support
using 'unstructured'.
New universal decoder service powered by the unstructured
library, handling DOCX, XLSX, PPTX, HTML, Markdown, CSV, RTF,
ODT, EPUB and more through a single service. Tables are preserved
as HTML markup for better downstream extraction. Images are
stored in the librarian but excluded from the text
pipeline. Configurable section grouping strategies
(whole-document, heading, element-type, count, size) for non-page
formats. Page-based formats (PDF, PPTX, XLSX) are automatically
grouped by page.
All four decoders (PDF, Mistral OCR, Tesseract OCR, universal)
now share the "document-decoder" ident so they are
interchangeable. PDF-only decoders fetch document metadata to
check MIME type and gracefully skip unsupported formats.
Librarian changes: removed MIME type whitelist validation so any
document format can be ingested. Simplified routing so text/plain
goes to text-load and everything else goes to document-load.
Removed dual inline/streaming data paths — documents always use
document_id for content retrieval.
New provenance entity types (tg:Section, tg:Image) and metadata
predicates (tg:elementTypes, tg:tableCount, tg:imageCount) for
richer explainability.
Universal decoder is in its own package (trustgraph-unstructured)
and container image (trustgraph-unstructured).
Page and chunk document IDs were deterministic ({doc_id}/p{num},
{doc_id}/p{num}/c{num}), causing "Document already exists" errors
when reprocessing documents through different flows. Content may
differ between runs due to different parameters or extractors, so
deterministic IDs are incorrect.
Pages now use urn:page:{uuid}, chunks use
urn:chunk:{uuid}. Parent- child relationships are tracked via
librarian metadata and provenance triples.
Also brings Mistral OCR and Tesseract OCR decoders up to parity
with the PDF decoder: librarian fetch/save support, per-page
output with unique IDs, and provenance triple emission. Fixes
Mistral OCR bug where only the first 5 pages were processed.
Tech spec
BlobStore (trustgraph-flow/trustgraph/librarian/blob_store.py):
- get_stream() - yields document content in chunks for streaming retrieval
- create_multipart_upload() - initializes S3 multipart upload, returns
upload_id
- upload_part() - uploads a single part, returns etag
- complete_multipart_upload() - finalizes upload with part etags
- abort_multipart_upload() - cancels and cleans up
Cassandra schema (trustgraph-flow/trustgraph/tables/library.py):
- New upload_session table with 24-hour TTL
- Index on user for listing sessions
- Prepared statements for all operations
- Methods: create_upload_session(), get_upload_session(),
update_upload_session_chunk(), delete_upload_session(),
list_upload_sessions()
- Schema extended with UploadSession, UploadProgress, and new
request/response fields
- Librarian methods: begin_upload, upload_chunk, complete_upload,
abort_upload, get_upload_status, list_uploads
- Service routing for all new operations
- Python SDK with transparent chunked upload:
- add_document() auto-switches to chunked for files > 10MB
- Progress callback support (on_progress)
- get_pending_uploads(), get_upload_status(), abort_upload(),
resume_upload()
- Document table: Added parent_id and document_type columns with index
- Document schema (knowledge/document.py): Added document_id field for
streaming retrieval
- Librarian operations:
- add-child-document for extracted PDF pages
- list-children to get child documents
- stream-document for chunked content retrieval
- Cascade delete removes children when parent is deleted
- list-documents filters children by default
- PDF decoder (decoding/pdf/pdf_decoder.py): Updated to stream large
documents from librarian API to temp file
- Librarian service (librarian/service.py): Sends document_id instead of
content for large PDFs (>2MB)
- Deprecated tools (load_pdf.py, load_text.py): Added deprecation
warnings directing users to tg-add-library-document +
tg-start-library-processing
Remove load_pdf and load_text utils
Move chunker/librarian comms to base class
Updating tests
