kraken 5.2.9 required torch~=2.1.0, incompatible with surya-ocr's
torch>=2.3.0. kraken 6.0.3 requires torch>=2.4.0,<=2.9 which
overlaps with surya and our pinned torch==2.5.1.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
surya-ocr 0.6.3 requires pillow<11.0.0,>=10.2.0. The previous
pin at 11.1.0 caused a dependency resolution failure during
Docker build.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Python microservice (ocr-service/):
- FastAPI app with /ocr and /health endpoints
- Surya engine: transformer-based OCR for typewritten/modern handwriting
- Kraken engine: historical HTR for Kurrent/Suetterlin with
pure-Python polygon-to-quad approximation (gift wrapping + rotating calipers)
- Eager model loading at startup via lifespan context manager
- PDF download via httpx, page rendering via pypdfium2 at 300 DPI
Java RestClientOcrClient:
- Implements OcrClient + OcrHealthClient interfaces
- Calls Python service via Spring RestClient
- Health check with graceful fallback
Docker Compose:
- New ocr-service container (mem_limit 6g, no host ports)
- Health check with start_period 60s for model loading
- ocr_models volume for Kraken model files
- Backend depends on ocr-service health
Refs #226, #227
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
