Ably iOS, tvOS and macOS Objective-C and Swift client library SDK
Ably is the platform that powers synchronized digital experiences in realtime. Whether attending an event in a virtual venue, receiving realtime financial information, or monitoring live car performance data – consumers simply expect realtime digital experiences as standard. Ably provides a suite of APIs to build, extend, and deliver powerful digital experiences in realtime for more than 250 million devices across 80 countries each month. Organizations like Bloomberg, HubSpot, Verizon, and Hopin depend on Ably’s platform to offload the growing complexity of business-critical realtime data synchronization at global scale. For more information, see the Ably documentation.
This is an iOS, tvOS and macOS Objective-C and Swift client library SDK for Ably, written in Objective-C. The library currently targets the Ably client library features spec Version 1.2. You can jump to the 'Known Limitations' section to see the features this client library does not yet support.
This SDK is compatible with projects that target:
- iOS 10.0+
- tvOS 10.0+
- macOS 10.12+
We maintain compatibility and explicitly support these platform versions.
We do not explicitly maintain compatibility with older platform versions. Any known incompatibilities with older versions can be found here.
If you find any issues with unsupported platform versions, please raise an issue in this repository or contact Ably customer support for advice.
We perform CI testing on the following operating systems:
- iOS 17.2
- tvOS 17.2
- The version of macOS specified by GitHub Actions’
macos-13
runner image.
This client library is currently not compatible with some of the Ably features:
Feature |
---|
Custom transportParams |
Remember fallback host during failures |
ErrorInfo URLs to help debug issues |
Visit ably.com/docs for a complete API reference and more examples.
You can install Ably for iOS and macOS through Package Manager, CocoaPods, Carthage or manually.
Installing through Swift Package Manager
- To install the
ably-cocoa
package in your Xcode Project:- Paste
https://github.com/ably/ably-cocoa
in the Swift Packages search box. ( Xcode project → Swift Packages.. . →+
button) - Select the
Ably
SDK for your target. - This apple guide explains the steps in more detail.
- Paste
- To install the
ably-cocoa
package in another Swift Package, then add the following to yourPackage.Swift
:
.package(url: "https://github.com/ably/ably-cocoa", from: "1.2.35"),
Installing through CocoaPods
If you intend to use Swift, using use_frameworks!
in your Podfile is recommended (this will create a Framework that can be used in Swift natively).
Add this line to your application's Podfile:
# For Xcode 7.3 and newer
pod 'Ably', '>= 1.2'
And then install the dependency:
$ pod install
Installing through Carthage
Add this line to your application's Cartfile:
# For Xcode 7.3 and newer
github "ably/ably-cocoa" >= 1.2
And then run
- for iOS:
carthage update --use-xcframeworks --platform iOS --no-use-binaries
- for macOS:
carthage update --use-xcframeworks --platform macOS --no-use-binaries
- for tvOS:
carthage update --use-xcframeworks --platform tvOS --no-use-binaries
to build the framework and drag the built (in [PROJECT_ROOT]/Carthage/Build
)
Ably.xcframework
AblyDeltaCodec.xcframework
msgpack.xcframework
into the "Frameworks, Libraries, and Embedded Content" section of the General tab of your Xcode target's settings. If your target is an application, select "Embed & Sign", otherwise "Do Not Embed".
If you see, for example, a dyld: Library not loaded: @rpath/AblyDeltaCodec.framework/AblyDeltaCodec
error, then most likely you forgot to add all the dependencies to your project. You have more detailed information here.
- Get the code from GitHub from the release page, or clone it to get the latest, unstable and possibly underdocumented version:
git clone [email protected]:ably/ably-cocoa.git
- Drag the directory
ably-cocoa/ably-cocoa
into your project as a group. - Ably depends on our MessagePack Fork 0.2.0; get it from the releases page and link it into your project.
The library makes the following thread-safety guarantees:
- The whole public interface can be safely accessed, both for read and writing, from any thread.
- "Value" objects (e. g.
ARTTokenDetails
, data from messages) returned by the library can be safely read from and written to. - Objects passed to the library must not be mutated afterwards. They can be safely passed again, or read from; they won't be written to by the library.
All internal operations are dispatched to a single serial GCD queue. You can specify a custom queue for this, which must be serial, with ARTClientOptions.internalDispatchQueue
.
All calls to callbacks provided by the user are dispatched to the main queue by default.
This allows you to react to Ably's output by doing UI operations directly. You can specify a different queue with ARTClientOptions.dispatchQueue
. It shouldn't be the same queue as the ARTClientOptions.internalDispatchQueue
, since that can lead to deadlocks.
If you haven’t yet, you should first check the detailed documentation. An example app for push notifications is also available.
For more information, see Push Notifications - Device activation and subscription.
ARTPushRegistererDelegate
defines 4 delegate methods to handle the outcome of push activation, deactivation and update events. By default, the Ably SDK will check if UIApplication.sharedApplication.delegate
conforms to ARTPushRegistererDelegate
, and call the delegate methods when appropriate. Therefore, specifying the ARTPushRegistererDelegate
is optional. To use a different class implementing ARTPushRegistererDelegate
, you must provide this class to Ably, by setting the ARTClientOptions.pushRegistererDelegate
delegate. In SwiftUI applications, you must set the ARTClientOptions.pushRegistererDelegate
delegate property.
Do not forget that ARTPush
has two corresponding methods that you should call from yours application(_:didRegisterForRemoteNotificationsWithDeviceToken:) and application(_:didFailToRegisterForRemoteNotificationsWithError:), passing to them also an ARTRest
or ARTRealtime
instance, configured with the authentication setup and other options you need:
func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
ARTPush.didRegisterForRemoteNotifications(withDeviceToken: deviceToken, rest: rest)
}
func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
ARTPush.didFailToRegisterForRemoteNotificationsWithError(error, rest: rest)
}
Only one instance of ARTRest
or ARTRealtime
at a time must be activated for receiving push notifications. Having more than one activated instance at a time may have unexpected consequences.
Starting with iOS 15, Apple supports power efficient way to request location trough location push service extension.
-
To receive location push notifications you need to request another device token specifically for the location pushes purpose. You do so by calling
CLLocationManager.startMonitoringLocationPushes(completion:)
within aARTPushRegistererDelegate.didActivateAblyPush(:)
delegate method (which is a callback for theARTRealtime.push.activate()
call). -
Once you receive the location push token, save it by calling a new
ARTPush.didRegisterForLocationNotifications(withDeviceToken:realtime:)
method (note the "Location" word in the name of this method). Ably will call theARTPushRegistererDelegate.didUpdateAblyPush:
callback on a successful or failed attempt to save the token.
Refer to the embed APNs example app on how this can be implemented.
Be aware that Push Notifications are currently unsupported for macOS and tvOS. You can only use the Push Admin functionalities, for example:
let recipient: [String: Any] = [
"clientId": "C04BC116-8004-4D78-A71F-8CA31.2.35DB"
]
let data: [String: Any] = [
"notification": [
"title": "Hello from Ably!",
"body": "Example push notification from Ably."
],
"data": [
"foo": "bar",
"baz": "qux"
]
]
realtime.push.admin.publish(recipient, data: data) { error in
print("Push published:", error ?? "nil")
}
Available demos: macOS and tvOS.
All examples assume a client has been created as follows:
Swift
// basic auth with an API key
let client = ARTRealtime(key: "xxxx:xxxx")
// using token auth
let client = ARTRealtime(token: "xxxx")
Objective-C
// basic auth with an API key
ARTRealtime* client = [[ARTRealtime alloc] initWithKey:@"xxxx:xxxx"];
// using token auth
ARTRealtime* client = [[ARTRealtime alloc] initWithToken:@"xxxx"];
Instantiating ARTRealtime
starts a connection by default. You can catch connection success or error by listening to the connection's state changes:
Swift
client.connection.on { stateChange in
let stateChange = stateChange!
switch stateChange.current {
case .Connected:
print("connected!")
case .Failed:
print("failed! \(stateChange.reason)")
default:
break
}
}
Objective-C
[client.connection on:^(ARTConnectionStateChange *stateChange) {
switch (stateChange.current) {
case ARTRealtimeConnected:
NSLog(@"connected!");
break;
case ARTRealtimeFailed:
NSLog(@"failed! %@", stateChange.reason);
break;
default:
break;
}
}];
You can also connect manually by setting the appropriate option.
Swift
let options = ARTClientOptions(key: "xxxx:xxxx")
options.autoConnect = false
let client = ARTRealtime(options: options)
client.connection.connect()
Objective-C
ARTClientOptions *options = [[ARTClientOptions alloc] initWithKey:@"xxxx:xxxx"];
options.autoConnect = false;
ARTRealtime *client = [[ARTRealtime alloc] initWithOptions:options];
[client.connection connect];
Given:
Swift
let channel = client.channels.get("test")
Objective-C
ARTRealtimeChannel *channel = [client.channels get:@"test"];
Subscribe to all events:
Swift
channel.subscribe { message in
print(message.name)
print(message.data)
}
Objective-C
[channel subscribe:^(ARTMessage *message) {
NSLog(@"%@", message.name);
NSLog(@"%@", message.data);
}];
Only certain events:
Swift
channel.subscribe("myEvent") { message in
print(message.name)
print(message.data)
}
Objective-C
[channel subscribe:@"myEvent" callback:^(ARTMessage *message) {
NSLog(@"%@", message.name);
NSLog(@"%@", message.data);
}];
Subscribing to a channel in delta mode enables delta compression. This is a way for a client to subscribe to a channel so that message payloads sent contain only the difference (ie the delta) between the present message and the previous message on the channel.
Request a Vcdiff formatted delta stream using channel options when you get the channel:
Swift
let channelOptions = ARTRealtimeChannelOptions()
channelOptions.params = [
"delta": "vcdiff"
]
let channel = client.channels.get("test", options: channelOptions)
Objective-C
ARTRealtimeChannelOptions *channelOptions = [[ARTRealtimeChannelOptions alloc] init];
channelOptions.params = @{
@"delta": @"vcdiff"
};
ARTRealtimeChannel *channel = [client.channels get:@"test" options:channelOptions];
Beyond specifying channel options, the rest is transparent and requires no further changes to your application. The message.data
instances that are delivered to your subscription callback continue to contain the values that were originally published.
If you would like to inspect the ARTMessage
instances in order to identify whether the data
they present was rendered from a delta message from Ably then you can see if message.extras["delta"]["format"]
equals "vcdiff"
.
Swift
channel.publish("greeting", data: "Hello World!")
Objective-C
[channel publish:@"greeting" data:@"Hello World!"];
Swift
channel.history { messagesPage, error in
let messagesPage = messagesPage!
print(messagesPage.items)
print(messagesPage.items.first)
print((messagesPage.items.first as? ARTMessage)?.data) // payload for the message
print(messagesPage.items.count) // number of messages in the current page of history
messagesPage.next { nextPage, error in
// retrieved the next page in nextPage
}
print(messagesPage.hasNext) // true, there are more pages
}
Objective-C
[channel history:^(ARTPaginatedResult<ARTMessage *> *messagesPage, ARTErrorInfo *error) {
NSLog(@"%@", messagesPage.items);
NSLog(@"%@", messagesPage.items.firstObject);
NSLog(@"%@", messagesPage.items.firstObject.data); // payload for the message
NSLog(@"%lu", (unsigned long)[messagesPage.items count]); // number of messages in the current page of history
[messagesPage next:^(ARTPaginatedResult<ARTMessage *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
NSLog(@"%d", messagesPage.hasNext); // true, there are more pages
}];
Swift
let channel = client.channels.get("test")
channel.presence.enter("john.doe") { errorInfo in
channel.presence.get { members, errorInfo in
// members is the array of members present
}
}
Objective-C
[channel.presence enter:@"john.doe" callback:^(ARTErrorInfo *errorInfo) {
[channel.presence get:^(ARTPaginatedResult<ARTPresenceMessage *> *result, ARTErrorInfo *error) {
// members is the array of members present
}];
}];
Swift
channel.presence.history { presencePage, error in
let presencePage = presencePage!
if let first = presencePage.items.first as? ARTPresenceMessage {
print(first.action) // Any of .Enter, .Update or .Leave
print(first.clientId) // client ID of member
print(first.data) // optional data payload of member
presencePage.next { nextPage, error in
// retrieved the next page in nextPage
}
}
}
Objective-C
[channel.presence history:^(ARTPaginatedResult<ARTPresenceMessage *> *presencePage, ARTErrorInfo *error) {
ARTPresenceMessage *first = (ARTPresenceMessage *)presencePage.items.firstObject;
NSLog(@"%lu", (unsigned long)first.action); // Any of ARTPresenceEnter, ARTPresenceUpdate or ARTPresenceLeave
NSLog(@"%@", first.clientId); // client ID of member
NSLog(@"%@", first.data); // optional data payload of member
[presencePage next:^(ARTPaginatedResult<ARTPresenceMessage *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
}];
A callback to call to obtain a signed token request.
ARTClientOptions
and ARTRealtime
objects can be instantiated as follow:
Swift
let clientOptions = ARTClientOptions()
clientOptions.authCallback = { params, callback in
getTokenRequestJSONFromYourServer(params) { json, error in
//handle error
do {
callback(try ARTTokenRequest.fromJson(json), nil)
} catch let error as NSError {
callback(nil, error)
}
}
}
let client = ARTRealtime(options:clientOptions)
Objective-C
ARTClientOptions *clientOptions = [[ARTClientOptions alloc] init];
clientOptions.authCallback = ^(ARTTokenParams *params, void(^callback)(id<ARTTokenDetailsCompatible>, NSError*)) {
[self getTokenRequestJSONFromYourServer:params completion:^(NSDictionary *json, NSError *error) {
//handle error
ARTTokenRequest *tokenRequest = [ARTTokenRequest fromJson:json error:&error];
callback(tokenRequest, error);
}];
};
ARTRealtime *client = [[ARTRealtime alloc] initWithOptions:clientOptions];
All examples assume a client and/or channel has been created as follows:
Swift
let client = ARTRest(key: "xxxx:xxxx")
let channel = client.channels.get("test")
Objective-C
ARTRest *client = [[ARTRest alloc] initWithKey:@"xxxx:xxxx"];
ARTRestChannel *channel = [client.channels get:@"test"];
Swift
channel.publish("myEvent", data: "Hello!")
Objective-C
[channel publish:@"myEvent" data:@"Hello!"];
Swift
channel.history { messagesPage, error in
let messagesPage = messagesPage!
print(messagesPage.items.first)
print((messagesPage.items.first as? ARTMessage)?.data) // payload for the message
messagesPage.next { nextPage, error in
// retrieved the next page in nextPage
}
print(messagesPage.hasNext) // true, there are more pages
}
Objective-C
[channel history:^(ARTPaginatedResult<ARTMessage *> *messagesPage, ARTErrorInfo *error) {
NSLog(@"%@", messagesPage.items.firstObject);
NSLog(@"%@", messagesPage.items.firstObject.data); // payload for the message
NSLog(@"%lu", (unsigned long)[messagesPage.items count]); // number of messages in the current page of history
[messagesPage next:^(ARTPaginatedResult<ARTMessage *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
NSLog(@"%d", messagesPage.hasNext); // true, there are more pages
}];
Swift
channel.presence.get { membersPage, error in
let membersPage = membersPage!
print(membersPage.items.first)
print((membersPage.items.first as? ARTPresenceMessage)?.data) // payload for the message
membersPage.next { nextPage, error in
// retrieved the next page in nextPage
}
print(membersPage.hasNext) // true, there are more pages
}
Objective-C
[channel.presence get:^(ARTPaginatedResult<ARTPresenceMessage *> *membersPage, ARTErrorInfo *error) {
NSLog(@"%@", membersPage.items.firstObject);
NSLog(@"%@", membersPage.items.firstObject.data); // payload for the message
[membersPage next:^(ARTPaginatedResult<ARTMessage *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
NSLog(@"%d", membersPage.hasNext); // true, there are more pages
}];
Swift
channel.presence.history { presencePage, error in
let presencePage = presencePage!
if let first = presencePage.items.first as? ARTPresenceMessage {
print(first.clientId) // client ID of member
presencePage.next { nextPage, error in
// retrieved the next page in nextPage
}
}
}
Objective-C
[channel.presence history:^(ARTPaginatedResult<ARTPresenceMessage *> *presencePage, ARTErrorInfo *error) {
ARTPresenceMessage *first = (ARTPresenceMessage *)presencePage.items.firstObject;
NSLog(@"%@", first.clientId); // client ID of member
NSLog(@"%@", first.data); // optional data payload of member
[presencePage next:^(ARTPaginatedResult<ARTPresenceMessage *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
}];
Swift
client.auth.requestToken(nil, withOptions: nil) { tokenDetails, error in
let tokenDetails = tokenDetails!
print(tokenDetails.token) // "xVLyHw.CLchevH3hF....MDh9ZC_Q"
let client = ARTRest(token: tokenDetails.token)
}
Objective-C
[client.auth requestToken:nil withOptions:nil callback:^(ARTTokenDetails *tokenDetails, NSError *error) {
NSLog(@"%@", tokenDetails.token); // "xVLyHw.CLchevH3hF....MDh9ZC_Q"
ARTRest *client = [[ARTRest alloc] initWithToken:tokenDetails.token];
}];
Swift
client.stats { statsPage, error in
let statsPage = statsPage!
print(statsPage.items.first)
statsPage.next { nextPage, error in
// retrieved the next page in nextPage
}
}
Objective-C
[client stats:^(ARTPaginatedResult<ARTStats *> *statsPage, ARTErrorInfo *error) {
NSLog(@"%@", statsPage.items.firstObject);
[statsPage next:^(ARTPaginatedResult<ARTStats *> *nextPage, ARTErrorInfo *error) {
// retrieved the next page in nextPage
}];
}];
Swift
client.time { time, error in
print(time) // 2016-02-09 03:59:24 +0000
}
Objective-C
[client time:^(NSDate *time, NSError *error) {
NSLog(@"%@", time); // 2016-02-09 03:59:24 +0000
}];
Please visit https://support.ably.com/ for access to our knowledgebase and to ask for any assistance.
You can also view the community reported Github issues.
See CONTRIBUTING.md for details.