--- title: "Push Gateway API" weight: 50 type: docs --- Clients may want to receive push notifications when events are received at the homeserver. This is managed by a distinct entity called the Push Gateway. ## Changelog **Version: %PUSH\_GATEWAY\_RELEASE\_LABEL%** {{push\_gateway\_changelog}} This version of the specification is generated from [matrix-doc](https://github.com/matrix-org/matrix-doc) as of Git commit [{{git\_version}}](https://github.com/matrix-org/matrix-doc/tree/%7B%7Bgit_rev%7D%7D). For the full historical changelog, see ### Other versions of this specification The following other versions are also available, in reverse chronological order: - [HEAD](https://matrix.org/docs/spec/push_gateway/unstable.html): Includes all changes since the latest versioned release. - [r0.1.0](https://matrix.org/docs/spec/push_gateway/r0.1.0.html) ## Overview A client's homeserver forwards information about received events to the push gateway. The gateway then submits a push notification to the push notification provider (e.g. APNS, GCM). ``` +--------------------+ +-------------------+ Matrix HTTP | | | | Notification Protocol | App Developer | | Device Vendor | | | | | +-------------------+ | +----------------+ | | +---------------+ | | | | | | | | | | | | Matrix homeserver +-----> Push Gateway +------> Push Provider | | | | | | | | | | | | +-^-----------------+ | +----------------+ | | +----+----------+ | | | | | | | Matrix | | | | | | Client/Server API + | | | | | | | +--------------------+ +-------------------+ | +--+-+ | | | <-------------------------------------------+ +---+ | | | Provider Push Protocol +----+ Mobile Device or Client ``` ## Homeserver behaviour This describes the format used by "HTTP" pushers to send notifications of events to Push Gateways. If the endpoint returns an HTTP error code, the homeserver SHOULD retry for a reasonable amount of time using exponential backoff. When pushing notifications for events, the homeserver is expected to include all of the event-related fields in the `/notify` request. When the homeserver is performing a push where the `format` is `"event_id_only"`, only the `event_id`, `room_id`, `counts`, and `devices` are required to be populated. Note that most of the values and behaviour of this endpoint is described by the Client-Server API's [Push Module](../client_server/%CLIENT_RELEASE_LABEL%.html#module-push). {{push\_notifier\_push\_http\_api}}