Get Started with Realm Web & Atlas Device Sync (Preview)

Import Realm

Importa el reino en la parte superior de tus archivos de origen donde interactúas con la base de datos:

import Realm, { App } from "realm";

Initialize an App

Device Sync uses Atlas App Services to manage authentication and sync data between devices. To use Device Sync from your web app, you must connect to an App Services App that has Device Sync enabled.

You connect to an App using its client App ID. To learn how to get it, see Find Your App ID.

const app = new App({ id: "<your-app-id>" });

Authenticate a User

Para autenticar a un usuario, llama al método App.logIn() en tu instancia de aplicación. Puedes iniciar sesión con cualquier proveedor de autenticación. Para obtener más ejemplos, consulta Autenticar a un usuario.

const credentials = Realm.Credentials.anonymous();
await app.logIn(credentials);

Define un modelo de objeto

Realm usa objetos nativos de JavaScript para modelar los datos de tu aplicación. Defines tipos de objetos donde todos los objetos de un tipo dado comparten un esquema que controla el contenido del objeto.

To define a Realm object type, create a schema object that specifies the type's name and properties. The type name must be unique among object types in a realm.

const TaskSchema = {
  name: "Task",
  properties: {
    _id: "int",
    name: "string",
    status: "string?",
    owner_id: "string?",
  },
  primaryKey: "_id",
};

Abrir un reino

To open a synced realm, call Realm.open() with a configuration object that specifies the realm's schema and includes a sync configuration object. The sync configuration should specify the authenticated user and define initial subscriptions that control which data is synced:

const realm = await Realm.open({
  schema: [TaskSchema],
  sync: {
    user: app.currentUser,
    flexible: true,
    // Define initial subscriptions to start syncing data as soon as the
    // realm is opened.
    initialSubscriptions: {
      update: (subs, realm) => {
        subs.add(
          // Get objects that match your object model, then filter them by
          // the `owner_id` queryable field
          realm.objects(Task).filtered(`owner_id == "${anonymousUser.id}"`)
        );
      },
    },
  },
});

Abre un Realm no sincronizado

To open a local, in-memory realm that does not sync, call Realm.open() with a local realm configuration object:

const realm = await Realm.open({
  schema: [TaskSchema]
});

Crear, modificar y eliminar objetos de Realm

Once you have opened a realm, you can create, modify, and delete objects in it. All write operations must occur within a Realm.write() transaction block.

const allTasks = realm.objects(Task);
// Add a couple of Tasks in a single, atomic transaction.
realm.write(() => {
  realm.create(Task, {
    _id: 1,
    name: "go grocery shopping",
    status: "Open",
  });
  realm.create(Task, {
    _id: 2,
    name: "go exercise",
    status: "Open",
  });
});
const task1 = allTasks.find((task) => task._id == 1);
const task2 = allTasks.find((task) => task._id == 2);
realm.write(() => {
  // Modify an object.
  task1!.status = "InProgress";
  // Delete an object.
  realm.delete(task2);
});

Find, Sort, and Filter Objects

Puedes query objetos en un realm usando el método Realm.objects(). Las consultas deben especificar el tipo de objeto Realm a consultar. Opcionalmente, puedes filtrar y ordenar los resultados de una query utilizando una API de cadena de métodos fluida.

// Query for specific obect using primary key.
const specificTask = realm.objectForPrimaryKey(Task, 0);
// Query realm for all instances of the "Task" type.
const tasks = realm.objects(Task);
// Filter for all tasks with a status of "Open".
const openTasks = tasks.filtered("status = 'Open'");
// Sort tasks by name in ascending order.
const tasksByName = tasks.sorted("name");

Close a Realm

Call the Realm.close() method when done with a realm instance to avoid memory leaks.

// Close the realm.
realm.close();