The disconnect detection is performed by a Web Connection Server.
There is no agreed-upon error-free detection strategy for a disconnection in the browser. To determine that a channel has been disconnected, one has to rely to a set of different methods for getting informed faster. These methods all ultimately rely on a "heartbeat" approach, whereby the browser is expected to provide a "heartbeat"-type signal within a fixed cycle. If one doesn't receive any heartbeat signal for some time, the assumption is that the browser got meanwhile disconnected. Based on the needs of the individual application, the rhythm of the heartbeat can be tuned satisfactorily. Different browsers behave differently when a disconnection occurs, so a generally valid notification method has to be implemented following the above guidelines, effective for all browser models. It is important to keep in mind that support for the Channel API will be turned off <https://cloud.google.com/appengine/docs/deprecations/channel> on October 31, 2017. The better product to replace the Channel API is the Firebase Database <https://firebase.google.com/>. For certain applications, Firebase Cloud Messaging would be the appropriate solution, as an alternative to some of the Channel API functions. For your purpose in particular, managing presence <https://firebase.google.com/docs/database/web/offline-capabilities> would be the one important feature of Firebase. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/de0ca55f-9abd-47ba-8653-5e744b1fc8a3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
