# HG changeset patch # User Matthew Wild # Date 1664007946 -3600 # Node ID 39c2824c28805108543ecf2dd86ea1f7ee454d9c # Parent c728e82265a7679b811b2bebe61e186fab9daa38 mod_cloud_notify: README overhaul diff -r c728e82265a7 -r 39c2824c2880 mod_cloud_notify/README.markdown --- a/mod_cloud_notify/README.markdown Sat Sep 24 08:28:07 2022 +0100 +++ b/mod_cloud_notify/README.markdown Sat Sep 24 09:25:46 2022 +0100 @@ -7,17 +7,62 @@ Introduction ============ -This is an implementation of the server bits of [XEP-0357: Push Notifications]. -It allows clients to register an "app server" which is notified about new -messages while the user is offline, disconnected or the session is hibernated -by [mod_smacks]. -Implementation of the "app server" is not included[^1]. +This module enables support for sending "push notifications" to clients that +need it, typically those running on certain mobile devices. -**Please note: Multi client setups don't work properly if MAM is disabled and using this module won't change this at all!** +As well as this module, your client must support push notifications (the apps +that need it generally do, of course) and the app developer's push gateway +must be reachable from your Prosody server (this happens over a normal XMPP +server-to-server 's2s' connection). Details ======= +Some platforms, notably Apple's iOS and many versions of Android, impose +limits that prevent applications from running or accessing the network in the +background. This makes it difficult or impossible for an XMPP application to +remain reliably connected to a server to receive messages. + +In order for messaging and other apps to receive notifications, the OS vendors +run proprietary servers that their OS maintains a permanent connection to in +the background. Then they provide APIs to application developers that allow +sending notifications to specific devices via those servers. + +When you connect to your server with an app that requires push notifications, +it will use this module to set up a "push registration". When you receive +a message but your device is not connected to the server, this module will +generate a notification and send it to the push gateway operated by your +application's developers). Their gateway will then connect to your device's +OS vendor and ask them to forward the notification to your device. When your +device receives the notification, it will display it or wake up the app so it +can connect to XMPP and receive any pending messages. + +This protocol is described for developers in [XEP-0357: Push Notifications]. + +For this module to work reliably, you must have [mod_smacks], [mod_mam] and +[mod_carbons] also enabled on your server. + +Some clients, notably Siskin and Snikket iOS need some additional extensions +that are not currently defined in a standard XEP. To support these clients, +see [mod_cloud_notify_extensions]. + +Configuration +============= + + Option Default Description + ------------------------------------ ----------------- ------------------------------------------------------------------------------------------------------------------- + `push_notification_important_body` `New Message!` The body text to use when the stanza is important (see above), no message body is sent if this is empty + `push_max_errors` `16` How much persistent push errors are tolerated before notifications for the identifier in question are disabled + `push_max_devices` `5` The number of allowed devices per user (the oldest devices are automatically removed if this threshold is reached) + `push_max_hibernation_timeout` `259200` (72h) Number of seconds to extend the smacks timeout if no push was triggered yet (default: 72 hours) + `push_notification_with_body` (\*) `false` Whether or not to send the real message body to remote pubsub node. Without end-to-end encryption, enabling this may expose your message contents to your client developers and OS vendor. Not recommended. + `push_notification_with_sender` (\*) `false` Whether or not to send the real message sender to remote pubsub node. Enabling this may expose your contacts to your client developers and OS vendor. Not recommended. + +(\*) There are privacy implications for enabling these options. + +Internal design notes +===================== + App servers are notified about offline messages, messages stored by [mod_mam] or messages waiting in the smacks queue. The business rules outlined [here](//mail.jabber.org/pipermail/standards/2016-February/030925.html) are all honored[^2]. @@ -45,32 +90,6 @@ can still see that the push is important. This is used by Chatsecure on iOS to send out high priority pushes in those cases for example. -Configuration -============= - - Option Default Description - ------------------------------------ ----------------- ------------------------------------------------------------------------------------------------------------------- - `push_notification_with_body` `false` Whether or not to send the real message body to remote pubsub node. Without end-to-end encryption, enabling this may expose your message contents to your client developers and OS vendor. Not recommended. - `push_notification_with_sender` `false` Whether or not to send the real message sender to remote pubsub node. Enabling this may expose your contacts to your client developers and OS vendor. Not recommended. - `push_max_errors` `16` How much persistent push errors are tolerated before notifications for the identifier in question are disabled - `push_notification_important_body` `New Message!` The body text to use when the stanza is important (see above), no message body is sent if this is empty - `push_max_devices` `5` The number of allowed devices per user (the oldest devices are automatically removed if this threshold is reached) - `push_max_hibernation_timeout` `6220800` Number of seconds to extend the smacks timeout if no push was triggered yet (default: 72 hours) - -There are privacy implications for enabling these options because -plaintext content and metadata will be shared with centralized servers -(the pubsub node) run by arbitrary app developers. - -Installation -============ - -Same as any other module. - -Configuration -============= - -Configured in-band by supporting clients. - Compatibility =============