Editing a product with additional nutrients will erroneously change the recorded values of these nutrients on save

[JeanFred]

Describe the bug

When editing a product with additional nutrients recorded (eg Vitamin D), the additional Nutrient values will be changed on save (even when not edited),

To Reproduce
Steps to reproduce the behavior:

1. Edit a product with at least one additional nutrient
2. Change something (eg a Label) (but not the nutrient)
3. Save

Expected behavior
The nutrient value do not get changed.

Actual behaviour
The nutrient value is divided by 1000.

Example
See my edits on the product https://world.openfoodfacts.org/product/4001497280001/ :

• Original version was https://world.openfoodfacts.org/product/4001497280001/hohes-c-orange?rev=31 −
  ** Vitamin C (ascorbic acid) | 35 mg
• Adding a label in https://world.openfoodfacts.org/product/4001497280001/hohes-c-orange?rev=32
  ** Vitamin C (ascorbic acid) | 0.035 mg
• Adding a packaging in https://world.openfoodfacts.org/product/4001497280001/hohes-c-orange?rev=33
  ** Vitamin C (ascorbic acid) | 0 mg |  

Smartphone (please complete the following information):

• Device: Fairphone 3+
• Version 3.6.8

[VaiTon]

More info: it happens only when selecting mg or ug

[VaiTon]

@teolemon @stephanegigandet

I inputed 10 mg and this is the result. Should we take the _value?

[teolemon]

Is this a sever side or client side issue @VaiTon ?

[stephanegigandet]

_value and _unit are internal data, they should not be read by the app. Use the _100g field instead. It is always in grams.

[VaiTon]

@stephanegigandet we need to use the _unit to set the unit spinner in the app.

Otherwise what abount taking the value in 100g and then finding the most appropriate unit?
cc @teolemon

[stephanegigandet]

Otherwise what abount taking the value in 100g and then finding the most appropriate unit?

That's the best thing to do.

[teolemon]

Ok, so my edits do not seem taken into account