How can we create an entity from json?

[AlexKenbo]

How can we create an entity from json? fromJson, toJson methods

[greenrobot]

Can you provide us examples where this is needed? What's the goal you want to achieve?

[AlexKenbo]

Can you provide us examples where this is needed? What's the goal you want to achieve?

In the date layer, we will receive json, for example: Next, we want to create an Entity there:

jsonOrder = getFromAPI('o-1256');
//{
//     "id": "o-1256",
//     "positions": [
//         {
//             "name": "iphone",
//             "quantity": 2
//         },
//         {
//             "name": "macbook",
//             "quantity": 1
//         }
//     ]
// }

// class Order {
//     String id;
//     List<Position> positions;
// } 

// class Position {
//     String name;
//     int quantity;
// } 

objboxOrder =Order.fromJson(jsonOrder);

Additional question. Can I get from the find-method one of the order positions, where name = iphone and change its quantity to 4? (Didn't find how to edit the fields. Just pick up the object and search for the position field in loops? And re-write to the box?)

objboxOrder.find(Position.name, 'iphone').set(Position.quantity, 4); // mutate objboxOrder And then I need to call the datasource.sendOrderToAPI(objboxOrder.toJson())

[greenrobot]

OK, this seems to intersect with https://flutter.dev/docs/development/data-and-backend/json.

JSON serialization with code generation means having an external library generate the encoding boilerplate for you. After some initial setup, you run a file watcher that generates the code from your model classes. For example, json_serializable and built_value are these kinds of libraries.

Did you try the approaches from the link?

It's not entirely impossible to have a more direct way of supporting JSON in ObjectBox in the future, but we should first evaluate how existing tools may already be helpful.

[AlexKenbo]

Did you try the approaches from the link?

We tried json_serializable, built_value

But we stopped at freezed which includes json_serializable, but is richer in functionality.

If we annotate freezed with an annotation class objectbox. Then we will have freezed methods for objectbox? copyWith, fromJson

[vaind]

As have been discussed above, there are libs to serialize to/from JSON and it's not in scope of ObjectBox to do that as well - it should rather be used in parallel with those packages. I don't even think OP wanted it to be in scope, just making it clear...

This looks like a duplicate of #229 please follow that one or reopen this if you think otherwise.

[vaind]

FYI I've just tried and https://pub.dev/packages/json_serializable works out of the box and you can use it with ObjectBox-dart 1.0 already... https://pub.dev/packages/freezed is a WIP