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Topics

Some services support subscribing to "topics".

This allows your server to send a message to multiple devices that have opted in to a particular topic.

Based on the publish/subscribe model, topic messaging supports unlimited subscriptions per app. The app server sends messages with payloads to the topic, and the service handles the message routing and delivers the message reliably to the right devices. For example, users of a weather forecasting app could opt in to a "severe weather alerts" topic and receive notifications of storms threatening specified areas.

Developers can choose any topic name that matches the regular expression, "[a-zA-Z0-9-_.~%]+"

Support​

Once you have setup your service you can query canSubscribeToTopics to find out whether the current service supports topics. This allows you to react to cases where the user has push notifications but no topic support (eg with APNS).

if (PushNotifications.service.canSubscribeToTopics)
{
    // Can subscribe to topics
}

Subscribe to a topic​

Subscrbing to a topic is as simple as calling subscribeToTopic with your topic name.

For example

PushNotifications.service.subscribeToTopic( "news" );

This function returns the success of the operation, a success does not ensure the topic was subscribed, only that the request to subscribe was made.

Note:

Once you have called subscribe it may take several hours for the topic to appear in your service console. Do not expect the topic to be created instantly.

Unsubscribe from a topic​

Similarly unsubscribing involves calling unsubscribeFromTopic with your topic name.

PushNotifications.service.unsubscribeFromTopic( "news" );