Proof images: allow users to upload PDFs

[raphodn]

Story

Some users receive their receipts through email, in a PDF format.
They currently need to take a screenshot of the receipt in order to upload it to Open Prices.

We could allow uploading PDFs instead, and transform them into images directly in the backend.

[raphael0202]

I gave it a try locally, it's already possible to send a PDF as a proof, which is correctly recognized as PDF by the backend (application/pdf mimetype):

$ http -vv -f POST http://127.0.0.1:8000/api/v1/proofs/upload Authorization:'Bearer raphael0202__U32031dfc-4aa1-42ba-9338-fa1007d2cbcd' file@'jzvj6BkWWT.webp;type=application/pdf' type=RECEIPT

HTTP/1.1 201 Created
Allow: POST
Connection: keep-alive
Content-Length: 398
Content-Type: application/json
Cross-Origin-Opener-Policy: same-origin
Date: Wed, 30 Oct 2024 17:13:53 GMT
Referrer-Policy: same-origin
Server: nginx/1.25.5
Vary: origin
X-Content-Type-Options: nosniff
X-Frame-Options: DENY

{
    "created": "2024-10-30T17:13:53.308943Z",
    "currency": null,
    "date": null,
    "file_path": "0001/4pF30LqQob.pdf",
    "id": 17,
    "image_thumb_path": null,
    "location": null,
    "location_id": null,
    "location_osm_id": null,
    "location_osm_type": null,
    "mimetype": "application/pdf",
    "owner": "raphael0202",
    "price_count": 0,
    "receipt_price_count": null,
    "receipt_price_total": null,
    "type": "PRICE_TAG",
    "updated": "2024-10-30T17:13:53.309166Z"
}

We can either create an image from the PDF, or support PDF display for proofs on the front-end.

[teolemon]

mogrify ?

[raphodn]

https://levelup.gitconnected.com/4-python-libraries-to-convert-pdf-to-images-7a09eba83a09

Library	Stars	Last version
pdf2image	1.6k	9 months ago
PyMuPDF	5.4k	2 days ago
?

Ideally 1 PDF --> 1 image (even if the PDF has multiple pages)