introduction to realm mobile platform
TRANSCRIPT
IntroducingRealm Mobile Platform
Build Better Apps Faster!
.
Christian Melchior@chrmelchior
About Realm• Headquartered in San Francisco, with engineering office
in Copenhagen • ~50 employees • Series B startup, $29M raised
Realm Mobile Database• On-device cross-platform object database • Launched July 2014 • Developed in the open, fully open source • 16K+ GitHub stars, 100K+ active developers
Developers Love Realm for Power, Simplicity, Ease of Use
Apps of Every Type, 1.000.000.000+ installs
Realm Mobile Platform
Users Expect More of Apps Today• Offline first: They need apps that work well offline and when network
connections are intermittent
• Reactive: They expect apps that are highly responsive, with all changes immediately reflected in the UI
• Real-time: They expect every user and device to stay in sync with each other in real-time
• Collaborative: They want highly collaborative features and experiences within their apps
• Seamless: They expect to be able to move seamlessly from device to device
The Apps You Want To Make
The AppYou Can MakePrice
Synchronisation is HARD
Deadlines
Crossplatform concerns
Backend team to busy
The Realm Mobile Platform
Realm Mobile DatabaseRealm Object Server
Real-time data sync
Realm Mobile
Database
Real-time Sync
Realm Object Server
SDKSDKSDK
Sync Engine Dashboard Auth
System
Encryption Layer
What is it?
Access Control Full DB access
Data connectorsObject Store
SD
SDK
SDK
Enterprise Feature
Event Framework
Developer priorities• Time-to-market: Your team need to be able to deliver quality apps
quickly and on time
• Ability: With high user expectations, the team need the ability to easily add advanced features like data sync, messaging and collaboration.
• Cross-platform: To reach the full audience, you need to be able to deliver apps for both iOS and Android
• Standardize: To manage all the apps and reduce complexity, you want to standardize on a single platform
The Reality With REST
REST is brittle and cumbersome in a mobile world• What happens when there is no connectivity?
• Queueing? • Persistence?
• What about connectivity being lost during requests? • Tokens? Do they have to be persisted in app? • State-full services?
• Resource intensive • Need for multiple REST calls. High latency cost • Often incurs duplication of data • JSON parsing is expensive
Delivers Key Mobile Solutions• Eliminates network challenges • Simplifies data architecture • Unlocks existing infrastructure
SDK1 2
• Offline-first • Full database on the device
• Queries run locally • Writes apply immediately
• Reactive architecture keeps UI up-to-date • Automatic sync happens in the background • Resilient to any network conditions
Eliminate Network Challenges
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
BuyObjectShoppingCart: →Status: nilOrderInfo: nil
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: “processing”OrderInfo: nil
BuyObjectShoppingCart: →Status: “processing”OrderInfo: nil
Objects as API’s
MobileServer
BuyObjectShoppingCart: →Status: “done”OrderInfo: → Realtime data sync
Objects as API’s
MobileServer
Realtime data sync
BuyObjectShoppingCart: →Status: “done”OrderInfo: →
BuyObjectShoppingCart: →Status: “done”OrderInfo: →
Delivers Key Mobile Solutions• Eliminates network challenges • Simplifies data architecture • Unlocks existing infrastructure
Typical Application Data Flow
Native object
JSON
Native object
SQL
Native object
JSON
Native object
SQLite SQLite
• It’s just objectson the device and on the server
• Objects are live,they update—automatically and immediately—in response to changes
• Not an ORM,the database is the data model
• Easier for developers to build, change, maintain
• Reduce code complexityvia unified data format; cross-platform
• Encrypted at rest & transitObjects all the way down
Simplify Data Architecture
Delivers Key Mobile Solutions• Eliminates network challenges • Simplifies data architecture • Unlocks existing infrastructure
Legacy Systems Hold Back Mobile
XML JSONRESTSOAP
/facilities /departments{"facility": "west-1A", "departments": [ {"type": "manufacturing"}, {"type": "operations"}]}
<?xml version="1.0" encoding="UTF-8" ?><root> <department>manufacturing</department> <facilities>west-1A</facilities></root>
Unlock Existing Infrastructure
DC9WP
Coupon:
Coupon:
DC9WP
coupon.code = DC9WP
coupon.isValid = true
1
2
3
• Bridge legacy APIs • Shift complexity to backend
• Node.js SDK • Identical object interface • Full database capabilities • Apply changes to push data
• Event framework • Listen and respond to changes from clients • Pass along data to other systems or databases
• Supports custom authentication
The code centric view
Realm is an object database
Create native objects that map directly to the database.
// Define you model class by extending RealmObject public class Dog extends RealmObject { public String name; // fields can also be private of course public int age = 1; // default values }
public class Person extends RealmObject { @PrimaryKey public long id; public String name; // support for custom logic in accessors public RealmList<Dog> dogs; // declare one-to-many relationships }
Perform complex queries across your object graph
RealmResults<User> result2 = realm.where(User.class) .equalTo("name", "John") .or() .equalTo("name", "Peter") .findAll();
RealmResults<User> result = realm.where(User.class).findAll(); result = result.sort("age"); // Sort ascending result = result.sort("age", Sort.DESCENDING);
All changes occur in transactions offering ACID compliance
// Obtain a Realm instance Realm realm = Realm.getDefaultInstance();
realm.beginTransaction(); Book cheeseBook = realm.createObject(Book.class); cheeseBook.title = "Gouda Recipes"; cheeseBook.id = 1; realm.commitTransaction();
But Realm objects have a special capability…
Realm objects live-update in response to changes
RealmResults<Dog> puppies = realm.where(Dog.class).lessThan("age", 2); puppies.length(); // => 0
realm.beginTransaction(); Dog myDog = realm.createObject(Dog.class); myDog.name = "Rex"; myDog.age = 1; realm.commitTransaction();
puppies.length(); // => 1
Realm is a live object databaseRealm is an object database
Listen for live object changes to simplify your architecture RealmResults<Person> persons = realm.where(Person.class).findAll(); persons.addChangeListener(new RealmChangeListener() { @Override public void onChange(RealmResults<Person> change) { // ... do something with the updates (UI, etc.) ... } });
Now imagine if these live-updates came from remote changes?
Realm Object Server synchronizes object changes in real-time.
Server-side Realms
Device-side Realms
Realm Object Server
Real-time Sync
Push object changes server-side instantly via Node.js interface
Authenticating a user
SyncCredentials me = SyncCredentials.usernamePassword(username, password, true); String authURL = "http://my.realm-auth-server.com:9080/auth"; SyncUser user = SyncUser.login(me, authURL);
Open a Realm instance and get ready for synchronization
RealmConfiguration conf = new RealmConfiguration.Builder().build();
String serverURL = "realm://my.realm-server.com/~/default"; SyncConfiguration conf = new SyncConfiguration.Builder(user, serverURL).build();
Realm realm = Realm.getInstance(conf); // Any changes made to this Realm will be synced across all devices!
Conflicts will occur! How do you handle them?
Conflict Resolution• Operational Transform
• Well-known documented solution. • Guarantee convergence.
• At field level
• Delete always wins • Last write wins • Inserts in Lists are ordered by time
• https://realm.io/docs/realm-object-server/#conflict-resolution
Trigger server-side functions based on data changes across Realms
Benefits for developers• Networking abstracted away. No need to worry about
connectivity, JSON parsing, object mapping…
• Unified Data Model. Same data format and reactivity on Client and Backend.
• Straight line from Server to UI. Data can be bound directly to UI on Client.
vs.
Ressources• RealmTasks https://github.com/realm/
RealmTasks • Realm Mobile Platform https://realm.io/
products/realm-mobile-platform/ • Realm Java https://realm.io/docs/java/latest/ • More demos https://github.com/realm-demos