com.pubnub.api.java.v2.entities.ChannelGroup.kt Maven / Gradle / Ivy
package com.pubnub.api.java.v2.entities
import com.pubnub.api.java.v2.subscriptions.Subscription
import com.pubnub.api.v2.entities.Subscribable
import com.pubnub.api.v2.subscriptions.SubscriptionOptions
/**
* A representation of a PubNub channel group identified by its [name].
*
* You can get a [Subscription] to this channel group through [Subscribable.subscription].
*
* Use the [com.pubnub.api.java.PubNub.channelGroup] factory method to create instances of this interface.
*/
interface ChannelGroup : com.pubnub.api.java.v2.entities.Subscribable {
/**
* The name of this channel group.
*
* See more in the [documentation](https://www.pubnub.com/docs/general/channels/subscribe#channel-groups)
*/
val name: String
/**
* Returns a [Subscription] that can be used to subscribe to this channel group.
*
* Channel group subscriptions support passing [com.pubnub.api.v2.subscriptions.SubscriptionOptions.receivePresenceEvents]
* in [options] to enable receiving presence events.
*
* [com.pubnub.api.v2.subscriptions.SubscriptionOptions.filter] can be used to filter events delivered to the subscription.
*
* For example, to create a subscription that only listens to presence events:
* ```
* channelGroup.subscription(SubscriptionOptions.receivePresenceEvents() + SubscriptionOptions.filter { it is PNPresenceEventResult } )
* ```
*
* *Warning:* if a channel is part of more than one channel group, and you create subscription to both (or more)
* those groups using a single [com.pubnub.api.PubNub] instance, you will only receive events for that channel in
* one channel group subscription.
*
* For example, let's say "channel_1" is part of groups "cg_1" and "cg_2". If you only subscribe to "cg_1",
* or you only subscribe to "cg_2", you will get all events for "channel_1". However, if in your app you subscribe
* to both "cg_1" and "cg_2" at the same time, you will only receive events for "channel_1" in one of those
* subscriptions, chosen at random.
*
* This limitation is due to how the server manages channels and channel groups.
*
* @param options optional [SubscriptionOptions].
* @return an inactive [Subscription] to this channel group. You must call [Subscription.subscribe] to start receiving events.
*/
override fun subscription(options: SubscriptionOptions): Subscription
/**
* Returns a [Subscription] that can be used to subscribe to this channel group.
*
* The returned [Subscription] is initially inactive. You must call [Subscription.subscribe] on it
* to start receiving events.
*
* @return An inactive [Subscription] to this channel.
*/
fun subscription(): Subscription
}