RealmJS

Realm is a mobile database that runs directly inside phones, tablets or wearables. This repository holds the source code for Realm's JavaScript bindings for integrating with mobile apps built using ReactNative and PhoneGap.

Setup

This repository uses submodules so you need to run git submodule update --init --recursive in the realm-js root directory before running any examples or including the project in your app.

ReactNative Example

Make sure your environment is set up to run react native applications. Follow the instructions here https://facebook.github.io/react-native/docs/getting-started.html.

The ReactNative example project is in the examples/ReactExample directory. You need to run npm install in this directory before running the example for the first time.

ReactNative Project Setup

• Create a new ReactNative project react-native init <project-name> and open the generated XCode project.
• Drag RealmJS.xcodeproj into the Libraries folder in your project.
• Drag RealmReact.framework from the Products directory under RealmJS.xcodeproj into the Embedded Libraries section in the General tab for your app's target settings. This bundles the library with your app.
• In the Build Phases tab for your app's target settings, add RealmReact.framework in the Target Dependencies and Link Binary with Library build phases.
• In your app's package.json file, add the realm dependency with a path to the realm-js/lib folder like this: "realm": "file:path/to/realm-js/lib" (symlinks are not yet supported by the React Native packager, see issue #637).
• You can now require('realm') in your app's JS to use Realm!

Getting Started

Start with creating a realm by defining its schema (object types and their properties):

const Realm = require('realm');

const realm = new Realm({
    schema: [
        {
            name: 'Person',
            properties: [
                {name: 'name', type: Realm.Types.STRING},
                {name: 'birthday', type: Realm.Types.DATE},
                {name: 'friends', type: Realm.Types.LIST, objectType: 'Person'},
            ]
        },
    ]
});

You can now use this realm to create new objects inside a write transaction:

realm.write(() => {
    ross = realm.create('Person', {
        name: 'Ross Geller',
        birthday: new Date(1967, 9, 18),
        friends: [chandler, joey, monica, phoebe, rachel],
    });
});

Remember you'll also need to modify and delete objects in write transactions:

realm.write(() => {
    rachel.friends.push(ross);
    realm.delete(janine);
});

Note: If an uncaught exception occurs during a write transaction, then object creations, deletions, and modifications will be undone.

You can query for existing objects by passing the object type and an optional query into the realm.objects() method:

let characters = realm.objects('Person');
let chandler = realm.objects('Person', 'name = "Chandler Bing"')[0];

If you'd prefer your objects inherit from a prototype, you just need to define the schema on the prototype object and instead pass in the constructor when creating a realm:

function Person() {}
Person.prototype = {
    schema: {
        name: 'Person',
        properties: [
            {name: 'name', type: Realm.Types.STRING},
            {name: 'birthday', type: Realm.Types.DATE},
            {name: 'friends', type: Realm.Types.LIST, objectType: 'Person'},
        ]
    },
    get age() {
        return Math.floor((Date.now() - this.birthday.getTime()) / 31557600000);
    },
};

const realm = new Realm({schema: [Person]});

You can see more examples of how to use these APIs in the ReactExample app and in the JS test files.

Documentation

Realm Constructor Options

• path – defaults to Realm.defaultPath (which initially is 'Documents/default.realm')
• schema – array of object type definitions (see below, optional if realm already created)
• schemaVersion – defaults to 0 (should be incremented after changing the schema)

Object Types

• name – string used to refer to this object type
• primaryKey – optional name of STRING or INT property that should be unique
• properties – array of property defitions (see below)

Property Types

When definining object properties in a schema, each should have a unique name, and the type of each property must be defined as either the name of an object type in the same schema or as one of the following:

• Realm.Types.BOOL
• Realm.Types.INT
• Realm.Types.FLOAT
• Realm.Types.DOUBLE
• Realm.Types.STRING
• Realm.Types.DATE
• Realm.Types.DATA
• Realm.Types.OBJECT (requires objectType, is always optional)
• Realm.Types.LIST (requires objectType, is never optional)

You may specify these property options as well:

• default – default value when property was not specified on creation
• optional – boolean indicating if this property may be assigned null or undefined

Realm Instance Methods

create(type, props, update)

• type – string matching object name in the schema definition
• props – object with property values for all required properties without a default value
• update – optional boolean signaling that an existing object (matching primary key) should be updated
• Returns a new realm object instance

delete(object)

• object – realm object or array of realm objects (which can be a List or Results object)

deleteAll()

WARNING: This does what you think it does!

objects(type, query)

• type – string matching object name in the schema definition
• query – optional string that defines a query to filter results (see tests for examples)
• Returns Results object

write(callback)

• callback – function that is synchronously called inside the write transaction

close()

WARNING: This is only for advanced use cases and generally doesn't need to be used.

License

Copyright 2015 Realm Inc - All Rights Reserved Proprietary and Confidential