Mobile integration for the new External Sources feature

[IWouldShiverTheWholeNightThrough]

We’ve just completed the web integration for our Empreinte Souffrance panel, see Pull Request #12235 openfoodfacts/openfoodfacts-server#12235
, which is nearly finished.

• Context
  Empreinte Souffrance (also known as L’Heure des Comptes) is a Data For Good project supported by Anima International. (see: https://website.services.dataforgood.fr/projets/l-empreinte-souffrance-des-produits-d-origine-animale )
  Our goal is to estimate an animal suffering footprint for food products.
  For now, we focus on eggs.

• What we did on the web
  While adding our panel, we also introduced a new Open Food Facts feature: External Sources.
  It allows partner organizations to attach their own information panels to product pages via the external_sources configuration.
  These panels can be user-activated (opt-in) and dynamically adapt to the product’s context.

• Next step: mobile integration
  We’d now like to bring this new External Sources system to the mobile app (Dart/Flutter).
  Pierre prepared a short technical document describing the required integration steps:

• Technical doc: https://docs.google.com/document/d/1jqZYtTMP5Hj5hQ-DcTcy1YQvoUXepyzsx2VzU-HEiOU/edit?usp=sharing

Since we’re not very experienced with Dart, we’d appreciate your advice or guidance on how to best approach this implementation on mobile.
If convenient, we’d be happy to schedule a short call or even meet in person (we’re based near Paris) to discuss it further.

Any help or insight from @monsieurtanuki, @g123k, or @teolemon would be greatly appreciated.

Thank you for your time and support,

[alexgarel]

IMPORTANT: also check out openfoodfacts/openfoodfacts-server#12070 to understand the greater scope.

[monsieurtanuki]

I'm available for a meeting in Paris next week.

[IWouldShiverTheWholeNightThrough]

great ! are you available on friday in the afternoon ? like around 5pm ?

[monsieurtanuki]

Friday 5pm is good for me.

[IWouldShiverTheWholeNightThrough]

Friday 5pm is good for me.

Perfect ! See you on friday

[monsieurtanuki]

See you!

[monsieurtanuki]

5pm at OFF's office avenue Victoria, right?

[alexgarel]

Here is the result that the API about external_sources will send back: https://github.com/IWouldShiverTheWholeNightThrough/openfoodfacts-server/tree/feature/external-sources-optin/tests/integration/expected_test_results/external_sources

(note: the PR of this branch is here)

[monsieurtanuki]

I've started pseudo coding this morning.

In dart we'll use a new filter class, with a filter method that will use the product type and categories as well as the current app country and language. Something like that

class ExternalSourceFilter{
  bool accepts(
    final Product product,
    final OpenFoodFactsLanguage language,
    final OpenFoodFactsCountry country,
  );

Regarding the knowledge panel url (currently http://127.0.0.1:8000/off/v1/knowledge-panel/$code?lang=$lc&country=$cc):

• what if we want several products at the same time, if we refresh several products in Smoothie for instance? Should we call several times that URL?
• lc and cc are 2-letter ISO codes (ISO 639 and ISO 3166-1 alpha-2)
• that would be slightly ugly to "string replace" $code, $lc and $cc in the URL

In short, if possible we should ask the external sources to

• provide a root URL, e.g. http://127.0.0.1:8000/off/v1/knowledge-panel/
• with GET (or POST) parameters code, lc and cc
• with code being comma separated barcodes, and the response being a map with barcodes as keys

[alexgarel]

@monsieurtanuki the PR is merged and visible on staging: https://world.openfoodfacts.net/api/v3/external_sources

[IWouldShiverTheWholeNightThrough]

Hi, i wondered @monsieurtanuki if you've started working on the dart part, if everything's alright or if you need further informations/support etc :D

[monsieurtanuki]

Oh, I've finished coding about a week ago: #1157

[IWouldShiverTheWholeNightThrough]

that's dope ! i wasn't aware you were already done with it, thx and congrats for the work that was faster than i'd have guessed !

[monsieurtanuki]

Well, once we agreed on the formats and the process, the rest was pure easy code.