OCR_AGENT environment variable is ignored - API always uses Tesseract

OCR_AGENT environment variable is ignored - API always uses Tesseract

Description

The OCR_AGENT environment variable is not respected by the API. Even when OCR_AGENT is set to use PaddleOCR (or any other OCR agent), the API always uses Tesseract because the ocr_agent parameter is never passed to the partition() function.

Steps to Reproduce

1. Build a container with PaddleOCR installed:

FROM downloads.unstructured.io/unstructured-io/unstructured-api:latest
RUN pip install "paddlepaddle>=3.0.0b1" "unstructured.paddleocr==2.10.0"
ENV OCR_AGENT=unstructured.partition.utils.ocr_models.paddle_ocr.OCRAgentPaddle

2. Start the container and send a PDF for processing

3. Observe that Tesseract is used instead of PaddleOCR:

$ docker exec unstructured ps aux | grep tesseract
tesseract /tmp/tess_xxx_input.PNG /tmp/tess_xxx -l eng -c tessedit_create_hocr=1

Expected Behavior

When OCR_AGENT environment variable is set, the API should use that OCR agent for processing.

Actual Behavior

The API ignores the OCR_AGENT environment variable and always uses Tesseract.

Root Cause

In prepline_general/api/general.py, the partition_kwargs dictionary does not include ocr_agent. The partition() function is called without this parameter, so it defaults to OCR_AGENT_TESSERACT.

The env_config.OCR_AGENT property correctly reads the environment variable, but it's never used when calling partition.

Current code (around line 580-600 in general.py):

partition_kwargs = {
    "strategy": strategy,
    "xml_keep_tags": xml_keep_tags,
    "languages": languages,
    # ... other params ...
    # NOTE: ocr_agent is missing!
}
elements = partition(**partition_kwargs)

Proposed Fix

Add ocr_agent to partition_kwargs:

from unstructured.partition.utils.config import env_config

partition_kwargs = {
    "strategy": strategy,
    "ocr_agent": env_config.OCR_AGENT,  # Add this line
    "xml_keep_tags": xml_keep_tags,
    # ... rest of params ...
}

Workaround

Patch the general.py file in the container:

RUN sed -i \
    -e '1a from unstructured.partition.utils.config import env_config' \
    -e 's/"strategy": strategy,/"strategy": strategy,\n            "ocr_agent": env_config.OCR_AGENT,/' \
    /home/notebook-user/prepline_general/api/general.py

Environment

• unstructured-api: latest (as of Dec 2024)
• unstructured: 0.18.18
• Docker image: downloads.unstructured.io/unstructured-io/unstructured-api:latest

Additional Context

This issue affects anyone trying to use an alternative OCR agent (PaddleOCR, Google Vision OCR) with the self-hosted API. The documentation at https://docs.unstructured.io/open-source/core-functionality/set-the-ocr-agent suggests setting the OCR_AGENT environment variable, but this doesn't work with the API due to this bug.

Start in prepline_general/api/general.py around the partition_kwargs construction described in the issue, and inspect how env_config.OCR_AGENT is read. Verify the API with OCR_AGENT set to PaddleOCR using the container reproduction steps; it is done when the configured OCR agent is passed through instead of defaulting to Tesseract.