Clarify the product quantity unit (g or mL)

[raphodn]

Story

For each new product we fetch from Open Food Facts its product_quantity, a normalized number in g or mL.

We need to find a way to know if the product is a beverage (mL), or solid (g), so that we can display the information accordingly in the frontend (price per kg or price per L).

Linked to #77

[raphodn]

@raphael0202 @teolemon any ideas ? maybe if we sync the products' categories ?
and should we store the info in the backend, or manage it instead in the frontend ?

[raphael0202]

In my opinion, we should fetch quantity from OFF and parse it to know whether it's a beverage or not.

[raphodn]

Isn't this parsing already done in OFF server ? Might be complex to manage all the use cases (kg, g, ml, L, pounds...).

Vs using the current clean and normalised field + a way to differenciate.

But if there is no way to differenciate in the other fields then...

[raphael0202]

It's done but there is no field to indicate the unit. We can also add a new field in Product Opener (but the codebase is in Perl)

[raphodn]

I'd go with a new field at the source !
It will probably help other projects or reuses

[raphodn]

Luckily a new field was recently added in Product Opener ! openfoodfacts/openfoodfacts-server#9377
Just need to wait to be able in prod 🙏

[raphodn]

@raphael0202 actually the new fields were in last month's release : https://github.com/openfoodfacts/openfoodfacts-server/releases/tag/v2.26.0

but i don't see them appearing in the v2 API ? is there some additional code to do ?

[raphael0202]

It's available on newly updated product (ex: https://world.openfoodfacts.org/api/v2/product/0044118115928.json).
To update all products and add the field, a script should be run server-side (update_all_products.pl).