HOWTO - Using the @quatrain/okf Adapter

This guide presents the most common usage scenarios for the OKF backend storage adapter.

1. Registering the OKF Adapter

To tell the Quatrain framework to persist models into local JSON files, register the OKFBackendAdapter in your application setup:

import { Backend } from '@quatrain/backend';
import { OKFBackendAdapter } from '@quatrain/okf';
 
const okfAdapter = new OKFBackendAdapter({
   config: {
      database: '/path/to/my/data/okf' // Root folder for JSON files
   }
});
 
// Set as default database backend
Backend.addBackend(okfAdapter, 'default', true);

2. Declaring Models and Saving Data

Define models inheriting from PersistedBaseObject:

import { PersistedBaseObject } from '@quatrain/backend';
import { StringProperty } from '@quatrain/core';
 
class Bassin extends PersistedBaseObject {
   static COLLECTION = 'bassins';
   static PROPS_DEFINITION = [
      { name: 'name', type: StringProperty.TYPE }
   ];
}

To save files, instantiate your model and save it:

const basin = await Bassin.factory();
basin.set('name', 'Bassin N°4');
basin.set('createdBy', 'pascal@sodav.ci'); // Injected in OKF meta block
 
await basin.save(); // Generates /path/to/my/data/okf/bassins/{uid}.json

3. Querying Local Files

Use the repository interface to search the flat-file structure:

const query = Bassin.query().filter('name', 'eq', 'Bassin N°4');
const results = await Bassin.repository().query(query);
 
results.items.forEach((item) => {
   console.log(item.val('name'));
});

Overview Overview