Apple Push Notification (APN) Provider for Go 1.6 and HTTP/2.

This release is a nearly feature complete. Please see releases for updates.

Buford uses Apple's new HTTP/2 Notification API that was announced at WWDC 2015 and released on December 17, 2015.

API documentation is available from GoDoc.

Also see Apple's Local and Remote Notification Programming Guide, especially the sections on the JSON payload and the Notification API. Also see Safari Push Notifications.

APN Apple Push Notification

Provider The Buford library is used to create a provider of push notifications.

Service Apple provides the push notification service that Buford communications with.

Client An http.Client provides an HTTP/2 client to communication with the APN Service.

Notification A payload sent to a device token with some headers.

Device Token An identifier for an application on a given device.

Payload The JSON sent to a device.

Headers HTTP/2 headers are used to for priority and expiration.

To use this library you can install Go 1.6 beta 1 binaries or install Go from source.

Other than the standard library, Buford depends on the pkcs12 package, which can be retrieved or updated with:

go get -u golang.org/x/crypto/pkcs12

The API is not yet stable. Please use a tool like Godep to vendor Buford and its dependencies in your project.

package main

import (
	"log"

	"github.com/RobotsAndPencils/buford/certificate"
	"github.com/RobotsAndPencils/buford/payload"
	"github.com/RobotsAndPencils/buford/payload/badge"
	"github.com/RobotsAndPencils/buford/push"
)

func main() {
	// set these variables appropriately
	filename := "/path/to/certificate.p12"
	password := ""
	deviceToken := "c2732227a1d8021cfaf781d71fb2f908c61f5861079a00954a5453f1d0281433"

	cert, err := certificate.Load(filename, password)
	if err != nil {
		log.Fatal(err)
	}

	service := push.Service{
		Client: push.NewClient(cert),
		Host:   push.Development,
	}

	p := payload.APS{
		Alert: payload.Alert{Body: "Hello HTTP/2"},
		Badge: badge.New(42),
	}

	id, err = service.Push(deviceToken, nil, p)
	if err != nil {
		log.Fatal(err)
	}
}

You can specify an ID, expiration, priority, and other parameters via the Headers struct.

headers := &push.Headers{
	ID:          "922D9F1F-B82E-B337-EDC9-DB4FC8527676",
	Expiration:  time.Now().Add(time.Hour),
	LowPriority: true,
}

id, err = service.Push(deviceToken, headers, p)

If no ID is specified APNS will generate and return a unique ID. When an expiration is specified, APNS will store and retry sending the notification until that time, otherwise APNS will not store or retry the notification. LowPriority should be used when sending a ContentAvailable payload.

To add custom values to an APS payload, use the Map method as follows:

p := payload.APS{
	Alert: payload.Alert{Body: "Message received from Bob"},
}
pm := p.Map()
pm["acme2"] = []string{"bang", "whiz"}

id, err = service.Push(deviceToken, nil, pm)

The Push method will use json.Marshal to serialize whatever you send it.

Use json.Marshal to serialize your payload once and then send it to multiple device tokens with PushBytes.

b, err := json.Marshal(p)
if err != nil {
	log.Fatal(err)
}

id, err := service.PushBytes(deviceToken, nil, b)

Whether you use Push or PushBytes the underlying HTTP/2 connection to APNS will be reused.