How to force paperless-ngx to consume signed PDFs

I use paperless-ngx to manage my documents, together with some rules that automaticaly ingest PDFs from my mail boxes. However, I noticed that a recently received invoice from AWS was not ingested as expected. Looking at the logs I found this error message for it:

invoice.pdf: Error occurred while consuming document invoice.pdf: DigitalSignatureError: Input PDF has a digital signature. OCR would alter the document,
invalidating the signature.

I don’t know if a software update brought this refusal to run OCR on signed PDFs, or if AWS simply so long didn’t send me signed PDFs, but I needed to find a way to force paperless to ingest signed things as well as having all of that stuff stored in paperless is a vital part of my accounting workflow.

A quick search for the error message brought me to this discussion on the paperless-ngx GitHub repository and therein I also found the solution, which is to set the PAPERLESS_OCR_USER_ARGS config option to {"invalidate_digital_signatures": true}.

As I run paperless via Docker I needed to add the following to the environment section in my paperless docker-compose.yml:

services:
  # ...
  paperless:
    # ...
    environment:
      # ...
      PAPERLESS_OCR_USER_ARGS: '{"invalidate_digital_signatures": true}'
      # ...

And after adding this and a quick docker compose up -d things seem to now work as expected again. Yay!