Configuration API for PubNub Swift Native SDK

Note

The PubNub Swift 3.0 SDK contains many significant changes from the 2.x SDK, including breaking changes. Please refer to the PubNub Swift 3.0 Migration Guide for more details.

A configuration object that defines behavior and policies for a PubNub instance

Initializer(s)

Description

Creates a configuration using the specified PubNub Publish and Subscribe Keys:

Method(s)

To Initialize PubNub you can use the following method(s) in the Swift SDK:

PubNubConfiguration(publishKey: String?, subscribeKey: String?)

Parameter	Type	Required	Defaults	Description
`publishKey`	String?	Optional	`nil`	Specifies the PubNub Publish Key to be used when publishing messages to a channel.
`subscribeKey`	String?	Yes	`nil`	Specifies the PubNub Subscribe Key to be used when subscribing to a channel.
`cipherKey`	Crypto?	Optional	`nil`	If set, all communication will be encrypted with this key.
`authKey`	String	Optional	`nil`	If Access Manager (PAM) is enabled, client will use authKey on all requests.
`uuid`	String	Optional	SDK generated random UUID	UUID to use. You should set a unique UUID to identify the user or the device that connects to PubNub. Allowing the SDK to generate a random UUID can result in significant billing impacts, particularly on an MAU pricing plan.
`useSecureConnections`	Bool	Optional	`true`	If `true`, requests will be made over HTTPS; otherwise they will use HTTP. You will still need to disable ATS for the system to allow insecure network traffic. See Apple's documentation for further details.
`origin`	String	Optional	`"ps.pndsn.com"`	Domain name used for requests.
`useInstanceId`	Bool	Optional	`false`	Whether a PubNub object instanceId should be included on outgoing requests.
`automaticRetry`	AutomaticRetry?	Optional	`nil`	Reconnection policy which will be used if/when a request fails.
`urlSessionConfiguration`	URLSessionConfiguration	Yes	`URLSessionConfiguration.pubnub`	`URLSessionConfiguration` used for `URLSession` network events.
`durationUntilTimeout`	Int	Optional	`300`	How long (in seconds) the server will consider the client alive for presence. Minimum value is `20`.
`heartbeatInterval`	UInt	Optional	`0`	How often (in seconds) the client will announce itself to server. Minimum value is 0.
`suppressLeaveEvents`	Bool	Optional	`false`	Whether to send out the leave requests.
`requestMessageCountThreshold`	UInt	Optional	`100`	The number of messages into the payload before emitting `RequestMessageCountExceeded`.
`filterExpression`	String?	Optional	`nil`	PSV2 feature to subscribe with a custom filter expression.

Basic Usage

Initialize the PubNub client API with a custom UUID:

Note

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. Not setting the UUID can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.

let config = PubNubConfiguration(
  publishKey: "demo",
  subscribeKey: "demo",
  uuid: "myUniqueUUID"
)

let pubnub = PubNub(configuration: config)

Other Examples

Initialization for a Read-Only client:

In the case where a client will only read messages and never publish to a channel, you can simply omit the publishKey when initializing the client:

Note

Always set the UUID to uniquely identify the user or device that connects to PubNub. This UUID should be persisted, and should remain unchanged for the lifetime of the user or the device. Not setting the UUID can significantly impact your billing if your account uses the Monthly Active Users (MAUs) based pricing model, and can also lead to unexpected behavior if you have Presence enabled.
```
let config = PubNubConfiguration(
  subscribeKey: "demo"
)
let pubnub = PubNub(configuration: config)
```

Event Listeners

Description

You can be notified of connectivity status, message, and presence notifications via the listeners.

Listeners should be added before calling the method.

Adding Listeners

// Create a new listener instance
let listener = SubscriptionListener()

// Add listener event callbacks
listener.didReceiveSubscription = { event in
  switch event {
  case let .messageReceived(message):
    print("Message Received: \(message) Publisher: \(message.publisher ?? "defaultUUID")")
  case let .connectionStatusChanged(status):
    print("Status Received: \(status)")
  case let .presenceChanged(presence):
    print("Presence Received: \(presence)")
  case let .subscribeError(error):
    print("Subscription Error \(error)")
  default:
    break
  }
}

// Start receiving subscription events
pubnub.add(listener)

Note

You can check the UUID of the publisher of a particular message by checking the message.publisher property in the subscription listener. You must also provide a default value for publisher, as the UUID parameter is optional.

Removing Listeners

The SubscriptionListener can be removed by either calling listener.cancel(), or by letting it fall out of scope and be removed as an autoreleased object.

Listener Subscription Events

This is the list of SubscriptionEvent case types that can be emitted from didReceiveSubscription, or grouped together using didReceiveBatchSubscription. Each event case also has a standalone listener that can save code space, but will be functionally equivalent to using didReceiveSubscription.

SubscriptionEvent Case	Event Type	Standalone Listener	Event Description
messageReceived	`PubNubMessage`	`didReceiveMessage`	Messages sent to subscribed channels/groups
signalReceived	`PubNubMessage`	`didReceiveSignal`	Signals sent to subscribed channels/groups
connectionStatusChanged	`ConnectionStatus`	`didReceiveStatus`	Changes in the connection to the PubNub system
subscriptionChanged	`SubscriptionChangeEvent`	`didReceiveSubscriptionChange`	Notifies when channels/groups are subscribed or unsubscribed
presenceChanged	`PubNubPresenceChange`	`didReceivePresence`	Presence changes on subscribed channels/groups tracking presence
uuidMetadataSet	`PubNubUUIDMetadataChangeset`	`didReceiveObjectMetadataEvent`	UUID metadata was set
uuidMetadataRemoved	`String`	`didReceiveObjectMetadataEvent`	UUID metadata was removed
channelMetadataSet	`PubNubChannelMetadataChangeset`	`didReceiveObjectMetadataEvent`	Channel metadata was set
channelMetadataRemoved	`String`	`didReceiveObjectMetadataEvent`	Channel metadata was removed
membershipMetadataSet	`PubNubMembershipMetadata`	`didReceiveObjectMetadataEvent`	Membership metadata was set
membershipMetadataRemoved	`PubNubMembershipMetadata`	`didReceiveObjectMetadataEvent`	Membership metadata was removed
messageActionAdded	`PubNubMessageAction`	`didReceiveMessageAction`	A `PubNubMessageAction` was added to a published message
messageActionRemoved	`PubNubMessageAction`	`didReceiveMessageAction`	A `PubNubMessageAction` was removed from a published message
subscribeError	`PubNubError`	`subscribeError`	Any error that might have occurred during the subscription stream

Basic Usage

This is an example using didReceiveBatchSubscription, to allow you to receive multiple events per event call

listener.didReceiveBatchSubscription = { events in
  for event in events {
    switch event {
    case .messageReceived(let message):
      print("The \(message.channel) channel received a message at \(message.published)")
      if let subscription = message.subscription {
        print("The channel-group or wildcard that matched this channel was \(subscription)")
      }
      print("The message is \(message.payload) and was sent by \(message.publisher ?? "")")
    case .signalReceived(let signal):
      print("The \(signal.channel) channel received a message at \(signal.published)")
      if let subscription = signal.subscription {
        print("The channel-group or wildcard that matched this channel was \(subscription)")
      }
      print("The signal is \(signal.payload) and was sent by \(signal.publisher ?? "")")
    case .connectionStatusChanged(let connectionChange):
      switch connectionChange {
      case .connecting:
        print("Status connecting...")
      case .connected:
        print("Status connected!")
      case .reconnecting:
        print("Status reconnecting...")
      case .disconnected:
        print("Status disconnected")
      case .disconnectedUnexpectedly:
        print("Status disconnected unexpectedly!")
      }
    case .subscriptionChanged(let subscribeChange):
      switch subscribeChange {
      case let .subscribed(channels, groups):
        print("\(channels) and \(groups) were added to subscription")
      case let .responseHeader(channels, groups, previous, next):
        print("\(channels) and \(groups) received a response at \(previous?.timetoken ?? 0)")
        print("\(next?.timetoken ?? 0) will be used as the new timetoken")
      case let .unsubscribed(channels, groups):
        print("\(channels) and \(groups) were removed from subscription")
      }
    case .presenceChanged(let presenceChange):
      print("The channel \(presenceChange.channel) has an updated occupancy of \(presenceChange.occupancy)")
      for action in presenceChange.actions {
        switch action {
        case let .join(uuids):
          print("The following list of occupants joined at \(presenceChange.timetoken): \(uuids)")
        case let .leave(uuids):
          print("The following list of occupants left at \(presenceChange.timetoken): \(uuids)")
        case let .timeout(uuids):
          print("The following list of occupants timed-out at \(presenceChange.timetoken): \(uuids)")
        case let .stateChange(uuid, state):
          print("\(uuid) changed their presence state to \(state) at \(presenceChange.timetoken)")
        }
      }
    case .uuidMetadataSet(let uuidMetadataChange):
      print("Changes were made to \(uuidMetadataChange.metadataId) at \(uuidMetadataChange.updated)")
      print("To apply the change, fetch a matching object and call `uuidMetadataChange.apply(to: otherUUIDMetadata)`")
    case .uuidMetadataRemoved(let metadataId):
      print("Metadata for the uuid \(metadataId) has been removed")
    case .channelMetadataSet(let channelMetadata):
      print("Changes were made to \(channelMetadata.metadataId) at \(channelMetadata.updated)")
      print("To apply the change, fetch a matching object and call `channelMetadata.apply(to: otherUUIDMetadata)`")
    case .channelMetadataRemoved(let metadataId):
      print("Metadata for the channel \(metadataId) has been removed")
    case .membershipMetadataSet(let membership):
      print("A membership was set between \(membership.uuidMetadataId) and \(membership.channelMetadataId)")
    case .membershipMetadataRemoved(let membership):
      print("A membership was removed between \(membership.uuidMetadataId) and \(membership.channelMetadataId)")
    case .messageActionAdded(let messageAction):
      print("The \(messageAction.channel) channel received a message at \(messageAction.messageTimetoken)")
      print("This action was created at \(messageAction.actionTimetoken)")
      print("This action has a type of \(messageAction.actionType) and has a value of \(messageAction.actionValue)")
    case .messageActionRemoved(let messageAction):
      print("The \(messageAction.channel) channel received a message at \(messageAction.messageTimetoken)")
      print("A message action with the timetoken of \(messageAction.actionTimetoken) has been removed")
    case .subscribeError(let error):
      print("The following error was generated during subscription \(error.localizedDescription)")
      print("If a `disconnectedUnexpectedly` also occurred then subscription has stopped, and needs to be restarted")
    }
  }
}

Other Examples

For didReceiveSubscription, simply rename the remove the for...in loop while keeping the event switch:

listener.didReceiveSubscription = { event in
  switch event {
  // Same content as the above example
  }
}

Overriding PubNub Configuration

All PubNubConfiguration properties are mutable, and can be changed after the object has been initialized. However, once the configuration is set on a PubNub instance those configurations are locked and can't be changed. Any changes would require a creating new PubNub instance.

UUID

var config = pubnub.configuration
config.uuid = "my_new_UUID"

let pubnub = PubNub(configuration: config)

Authentication

var config = pubnub.configuration
config.authKey = "my_new_authkey"

let pubnub = PubNub(configuration: config)

Filter

You can override the subscribe filter expression without creating a new PubNub instance in one of two ways.

Note

These are functionally equivalent, and will take effect on the next subscription request and persist until changed.

In combination with a subscribe change:

pubnub.subscribe(to: ["new_subscription"], filterOverride: "(senderID=='my_new_UUID')")

Without needing to make a subscription change:

pubnub.subscribeFilterExpression = "(senderID=='my_new_UUID')"