RxRealm

Usage

This library is a thin wrapper around RealmSwift.

NB: For Swift 3 projects add this snippet to the bottom of your project's Podfile. This will update your targets to use swift3:

post_install do |installer|
    installer.pods_project.targets.each do |target|
        target.build_configurations.each do |config|
            config.build_settings['SWIFT_VERSION'] = '3.0'
            config.build_settings['MACOSX_DEPLOYMENT_TARGET'] = '10.10'
        end
    end
end

Observing collections

RxRealm can be used to create Observables from objects of type Results, List, LinkingObjects or AnyRealmCollection as follows:

Observable.from(_:)

Emits every time the collection changes

let realm = try! Realm()
let laps = realm.objects(Lap.self)

Observable.from(laps)
  .map { 
    laps in "\(laps.count) laps"
  }.subscribe(onNext: { text  in
    print(text)
  })

Observable.arrayFrom(_:)

Fetches the a snapshot of a Realm collection and converts it to an array value (for example if you want to use array methods on the collection)

let realm = try! Realm()
let laps = realm.objects(Lap.self)

Observable.arrayFrom(laps)
  .map { array in
    return array.prefix(3) //slice of first 3 items
  }.subscribe(onNext: { text  in
    print(text)
  })

Observable.changesetFrom(_:)

Emits every time the collection changes and provides the exact indexes that has been deleted, inserted or updated

let realm = try! Realm()
let laps = realm.objects(Lap.self))

Observable.changesetFrom(laps)
  .subscribe(onNext: { results, changes in
    if let changes = changes {
    // it's an update
    print(results)
    print("deleted: \(changes.deleted) inserted: \(changes.inserted) updated: \(changes.updated)")
  } else {
    // it's the initial data
    print(results)
  }
  })

Observable.changesetArrayFrom(_:)

Combines the result of Observable.arrayFrom(_:) and Observable.changesetFrom(_:) returning an Observable<Array<T>, RealmChangeset?>

let realm = try! Realm()
let laps = realm.objects(Lap.self))

Observable.changesetArrayFrom(laps)
  .subscribe(onNext: { array, changes in
    if let changes = changes {
    // it's an update
    print(array.first)
    print("deleted: \(changes.deleted) inserted: \(changes.inserted) updated: \(changes.updated)")
  } else {
    // it's the initial data
    print(array)
  }
  })

Observing a single object

There's a separate API to make it easier to observe single object (it creates Results behind the scenes):

Observable.from(ticker)
    .map({ (ticker) -> String in
        return "\(ticker.ticks) ticks"
    })
    .bindTo(footer.rx.text)

This API uses the primary key of the object to query the database for it and observe for change notifications. Observing objects without a primary key does not work.

Performing transactions

rx.add()

Writing to an existing Realm reference

You can add newly created objects to a Realm that you already have initialized:

let realm = try! Realm()
let messages = [Message("hello"), Message("world")]

Observable.from(messages)
  .subscribe(realm.rx.add())

Be careful, this will retain your Realm until the Observable completes or errors out.

Writing to the default Realm

You can leave it to RxRealm to grab the default Realm on any thread your subscribe and write objects to it:

let messages = [Message("hello"), Message("world")]

Observable.from(messages)
  .subscribe(Realm.rx.add())

Writing to a specific Realm

If you want to switch threads and not use the default Realm, provide a Realm.Configuration:

var config = Realm.Configuration()
/* custom configuration settings */

let messages = [Message("hello"), Message("world")]
Observable.from(messages)
  .observeOn( /* you can switch threads if you want to */ )     
  .subscribe(Realm.rx.add(configuration: config))

If you want to create a Realm on a different thread manually, allowing you to handle errors, you can do that too:

let messages = [Message("hello"), Message("world")]

Observable.from(messages)
  .observeOn( /* you can switch threads if you want to */ )
  .subscribe(onNext: {messages in
    let realm = try! Realm()
    try! realm.write {
      realm.add(messages)
    }
  })

rx.delete()

#####Deleting from an existing realm reference

let realm = try! Realm()
let messages = realm.objects(Message.self)
Observable.from(messages)
  .subscribe(realm.rx.delete())

Be careful, this will retain your realm until the Observable completes or errors out.

#####Deleting from the object's realm automatically You can leave it to RxRealm to grab the Realm from the first object and use it:

Observable.from(someCollectionOfPersistedObjects)
  .subscribe(Realm.rx.delete())

Example app

To run the example project, clone the repo, and run pod install from the Example directory first. The app uses RxSwift, RxCocoa using RealmSwift, RxRealm to observe Results from Realm.

Further you're welcome to peak into the RxRealmTests folder of the example app, which features the library's unit tests.

Installation

This library depends on both RxSwift and RealmSwift 1.0+.

CocoaPods

RxRealm is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod "RxRealm"

Carthage

RxRealm is available through Carthage. You can install Carthage with Homebrew using the following command:

$ brew update
$ brew install carthage

To integrate RxRealm into your Xcode project using Carthage, specify it in your Cartfile:

github "RxSwiftCommunity/RxRealm" ~> 1.0

Run carthage update to build the framework and drag the built RxRealm.framework into your Xcode project.

As Source

You can grab the files in Pod/Classes from this repo and include them in your project.

TODO

Test add platforms and add compatibility for the pod

License

This library belongs to RxSwiftCommunity.

RxRealm is available under the MIT license. See the LICENSE file for more info.

reloni / RxRealm