1 files changed, 175 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/anachronistic/apns/push_notification.go b/Godeps/_workspace/src/github.com/anachronistic/apns/push_notification.go
new file mode 100644
index 000000000..e6b58d575
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/anachronistic/apns/push_notification.go
@@ -0,0 +1,175 @@
+package apns
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"math/rand"
+	"strconv"
+	"time"
+)
+
+// Push commands always start with command value 2.
+const pushCommandValue = 2
+
+// Your total notification payload cannot exceed 2 KB.
+const MaxPayloadSizeBytes = 2048
+
+// Every push notification gets a pseudo-unique identifier;
+// this establishes the upper boundary for it. Apple will return
+// this identifier if there is an issue sending your notification.
+const IdentifierUbound = 9999
+
+// Constants related to the payload fields and their lengths.
+const (
+	deviceTokenItemid            = 1
+	payloadItemid                = 2
+	notificationIdentifierItemid = 3
+	expirationDateItemid         = 4
+	priorityItemid               = 5
+	deviceTokenLength            = 32
+	notificationIdentifierLength = 4
+	expirationDateLength         = 4
+	priorityLength               = 1
+)
+
+// Payload contains the notification data for your request.
+//
+// Alert is an interface here because it supports either a string
+// or a dictionary, represented within by an AlertDictionary struct.
+type Payload struct {
+	Alert            interface{} `json:"alert,omitempty"`
+	Badge            int         `json:"badge,omitempty"`
+	Sound            string      `json:"sound,omitempty"`
+	ContentAvailable int         `json:"content-available,omitempty"`
+	Category         string      `json:"category,omitempty"`
+}
+
+// NewPayload creates and returns a Payload structure.
+func NewPayload() *Payload {
+	return new(Payload)
+}
+
+// AlertDictionary is a more complex notification payload.
+//
+// From the APN docs: "Use the ... alert dictionary in general only if you absolutely need to."
+// The AlertDictionary is suitable for specific localization needs.
+type AlertDictionary struct {
+	Body         string   `json:"body,omitempty"`
+	ActionLocKey string   `json:"action-loc-key,omitempty"`
+	LocKey       string   `json:"loc-key,omitempty"`
+	LocArgs      []string `json:"loc-args,omitempty"`
+	LaunchImage  string   `json:"launch-image,omitempty"`
+}
+
+// NewAlertDictionary creates and returns an AlertDictionary structure.
+func NewAlertDictionary() *AlertDictionary {
+	return new(AlertDictionary)
+}
+
+// PushNotification is the wrapper for the Payload.
+// The length fields are computed in ToBytes() and aren't represented here.
+type PushNotification struct {
+	Identifier  int32
+	Expiry      uint32
+	DeviceToken string
+	payload     map[string]interface{}
+	Priority    uint8
+}
+
+// NewPushNotification creates and returns a PushNotification structure.
+// It also initializes the pseudo-random identifier.
+func NewPushNotification() (pn *PushNotification) {
+	pn = new(PushNotification)
+	pn.payload = make(map[string]interface{})
+	pn.Identifier = rand.New(rand.NewSource(time.Now().UnixNano())).Int31n(IdentifierUbound)
+	pn.Priority = 10
+	return
+}
+
+// AddPayload sets the "aps" payload section of the request. It also
+// has a hack described within to deal with specific zero values.
+func (pn *PushNotification) AddPayload(p *Payload) {
+	// This deserves some explanation.
+	//
+	// Setting an exported field of type int to 0
+	// triggers the omitempty behavior if you've set it.
+	// Since the badge is optional, we should omit it if
+	// it's not set. However, we want to include it if the
+	// value is 0, so there's a hack in push_notification.go
+	// that exploits the fact that Apple treats -1 for a
+	// badge value as though it were 0 (i.e. it clears the
+	// badge but doesn't stop the notification from going
+	// through successfully.)
+	//
+	// Still a hack though :)
+	if p.Badge == 0 {
+		p.Badge = -1
+	}
+	pn.Set("aps", p)
+}
+
+// Get returns the value of a payload key, if it exists.
+func (pn *PushNotification) Get(key string) interface{} {
+	return pn.payload[key]
+}
+
+// Set defines the value of a payload key.
+func (pn *PushNotification) Set(key string, value interface{}) {
+	pn.payload[key] = value
+}
+
+// PayloadJSON returns the current payload in JSON format.
+func (pn *PushNotification) PayloadJSON() ([]byte, error) {
+	return json.Marshal(pn.payload)
+}
+
+// PayloadString returns the current payload in string format.
+func (pn *PushNotification) PayloadString() (string, error) {
+	j, err := pn.PayloadJSON()
+	return string(j), err
+}
+
+// ToBytes returns a byte array of the complete PushNotification
+// struct. This array is what should be transmitted to the APN Service.
+func (pn *PushNotification) ToBytes() ([]byte, error) {
+	token, err := hex.DecodeString(pn.DeviceToken)
+	if err != nil {
+		return nil, err
+	}
+	if len(token) != deviceTokenLength {
+		return nil, errors.New("device token has incorrect length")
+	}
+	payload, err := pn.PayloadJSON()
+	if err != nil {
+		return nil, err
+	}
+	if len(payload) > MaxPayloadSizeBytes {
+		return nil, errors.New("payload is larger than the " + strconv.Itoa(MaxPayloadSizeBytes) + " byte limit")
+	}
+
+	frameBuffer := new(bytes.Buffer)
+	binary.Write(frameBuffer, binary.BigEndian, uint8(deviceTokenItemid))
+	binary.Write(frameBuffer, binary.BigEndian, uint16(deviceTokenLength))
+	binary.Write(frameBuffer, binary.BigEndian, token)
+	binary.Write(frameBuffer, binary.BigEndian, uint8(payloadItemid))
+	binary.Write(frameBuffer, binary.BigEndian, uint16(len(payload)))
+	binary.Write(frameBuffer, binary.BigEndian, payload)
+	binary.Write(frameBuffer, binary.BigEndian, uint8(notificationIdentifierItemid))
+	binary.Write(frameBuffer, binary.BigEndian, uint16(notificationIdentifierLength))
+	binary.Write(frameBuffer, binary.BigEndian, pn.Identifier)
+	binary.Write(frameBuffer, binary.BigEndian, uint8(expirationDateItemid))
+	binary.Write(frameBuffer, binary.BigEndian, uint16(expirationDateLength))
+	binary.Write(frameBuffer, binary.BigEndian, pn.Expiry)
+	binary.Write(frameBuffer, binary.BigEndian, uint8(priorityItemid))
+	binary.Write(frameBuffer, binary.BigEndian, uint16(priorityLength))
+	binary.Write(frameBuffer, binary.BigEndian, pn.Priority)
+
+	buffer := bytes.NewBuffer([]byte{})
+	binary.Write(buffer, binary.BigEndian, uint8(pushCommandValue))
+	binary.Write(buffer, binary.BigEndian, uint32(frameBuffer.Len()))
+	binary.Write(buffer, binary.BigEndian, frameBuffer.Bytes())
+	return buffer.Bytes(), nil
+}