Weird behavior with the cache

[teolemon]

What

• Weird behavior with the cache https://github.com/openfoodfacts/smooth-app/assets/1689815/9077dec5-5055-4935-aff4-d2959ead92db

[monsieurtanuki]

@teolemon Can you elaborate a little? I have no idea what you're complaining about.

[teolemon]

Missing data to compute Nutri-Score + Prompt to complete product, while everything is actually already there, and the fasttrack promo disappears if you refresh the product. The video needs to be paused, but it should be quite explicit

[monsieurtanuki]

1. you scanned a product
2. on the product page you see
   1. the "3 questions" button
   2. the "missing data for nutriscore" button
   3. a computed ecoscore
3. you click on the "missing data for nutriscore" button
4. you see a "missing nutrition facts" button, and you click on it
5. ... but the nutrition facts are already populated, so you didn't expect a "missing nutrition facts" button in the first place, right?
6. you click back to the product page, and click on the "3 questions" button
7. you see that nutriscore is not computed, though the category and the nutrition facts are not empty
8. for some reason, then you go to the edit ingredient OCR page

What I can say is:

1. the "missing data for nutriscore" button is from KP, which is potentially not refreshed at the same time as the rest of the product. More specifically, as we use background tasks, we do set for instance the category immediately locally, while the edits are uploaded to the server. So we have locally a visible category, that is not yet on the server, so we don't have the nutriscore yet. When the category is indeed uploaded, we download the product (including fresh nutriscore and KP) and refresh it locally. I think that's what is bothering you here. It's not a problem of cache, it's a matter of Smoothie depending on the server for scores and KP.
2. the nutriscore needs specific nutrient values to be populated (e.g. fat), so you can have populated nutrition facts but not computed nutriscore
3. the "3 questions" button was correct, as the ingredients were not populated at all. As already mentioned, I would be less confusing to have tailored labels (e.g. "Answer 1 question about the ingredients and compute the eco-score")
4. "the fasttrack promo disappears if you refresh the product." it's not in the video, right?

[monsieurtanuki]

Possible solutions:

• for some "important" fields (like category), sync server call instead of background task - we'll get scores computed from the server
• for some computed fields (scores, KP), indicate that (related?) fields are temporarily out-of-sync (during background tasks) (red spot at the computed field level?)
• more generally, indicate that a product is temporarily out-of-sync (red spot at the product level?)
• compute some scores locally - but that would probably be very problematic for "category" and "ingredients" given their range and the localizations