Is there a guide to writing Models in Typescript?

[rjmatthews62]

I would like to be able to write the model definition files in Typescript. In particular, all my attempts so far have failed when trying to use decorations... I believe the babel plugins may be fighting with the inbuild TS decorations....

[rjmatthews62]

So, turns out there ARE some typescript examples provided: here

The key takeaways seem to be add emitDecoratorMetadata and experimentalDecorators to tsconfig.json:

{
  "extends": "@react-native/typescript-config/tsconfig.json",
  "compilerOptions": {
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
  }
}

(This is for react native 0.79.0)
Rename the model from *.js to *.ts and explicitly provide types for, ie, associations and the fields. Note also that I have here provided initialisers for the fields, otherwise I have to allow for undefined... I'll be honest, this is not required in the examples: there might be a setting somewhere.

// model/Post.ts
import { Model } from '@nozbe/watermelondb';
import { field, text, date } from '@nozbe/watermelondb/decorators';
import { Associations } from '@nozbe/watermelondb/Model';

export default class Post extends Model {
    static table = 'posts';
    static associations:Associations = {
        comments: { type: 'has_many', foreignKey: 'post_id' },
    };
    @text('title') title:string="";
    @text('body') body:string="";
    @field('is_pinned') isPinned:boolean=false;
    @date('last_event_at') lastEventAt:boolean=false;
}