New Command 2 Apple Push Notification Not sending multiple alerts

2
votes

I am trying to implement the new 'Command 2' push notification in Java and cannot have it push multiple alerts. First alert is pushed successfully. Please help if you can spot any issue on this code

Apple specs https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/CommunicatingWIthAPS.html#//apple_ref/doc/uid/TP40008194-CH101-SW1

for (DeviceApps deviceApps : deviceAppsList) {
outputStream.write(getByteArray(deviceApps, pushAlert));
}


private byte[] getByteArray(DeviceApps deviceApps, PushAlert pushAlert) {

ByteArrayOutputStream dataBao = new ByteArrayOutputStream();
// Write the TokenLength as a 16bits unsigned int, in big endian
dataBao.write((byte)1);
 dataBao.write(intTo2ByteArray(32));
dataBao.write(deviceTokenAsBytes);

// Write the PayloadLength as a 16bits unsigned int, in big endian
 dataBao.write((byte)2);
dataBao.write(intTo2ByteArray(payLoadAsBytes.length));
dataBao.write(payLoadAsBytes);

// 4 bytes. Notification identifier
dataBao.write((byte)3);
dataBao.write(intTo2ByteArray(4));
dataBao.write(intTo4ByteArray(random.nextInt()));

// 4 bytes Expiration date
dataBao.write((byte)4);
dataBao.write(intTo2ByteArray(4));
dataBao.write(intTo4ByteArray(pushAlert.getUtcExpireTime()));
LOG.error("UtcExpireTime="+ pushAlert.getUtcExpireTime());

// 1 bytes Priority
dataBao.write((byte)5);
dataBao.write(intTo2ByteArray(1));
dataBao.write((byte)10);


//Frame Info
bao = new ByteArrayOutputStream();
bao.write((byte)2);
byte [] data = dataBao.toByteArray();
bao.write(intTo4ByteArray(data.length));
LOG.error(" data.length "+data.length);
bao.write(data);

return bao.toByteArray();               
}


Support Methods
private static final byte[] intTo4ByteArray(int value) {
return ByteBuffer.allocate(4).putInt(value).array();
}

private static final byte[] intTo2ByteArray(int value) {
int s1 = (value & 0xFF00) >> 8;
    int s2 = value & 0xFF;
    return new byte[] { (byte) s1, (byte) s2 };
}
3
ioscommandapple-push-notificationspush
Why not just use a library that already implements the APNS functionality like code.google.com/p/javapns? – Alcanzar
They do not have this implemented. I checked the source code. – Muthee
I tested with the javaapns code a while back and it did work... I based my own implementation on some of what I saw there... The implementation itself didn't meet my particular needs though. – Alcanzar
Javaapns works for old commands (0 and 1) but they have not implemented the new one - 2 – Muthee
Javapns does not implement command 2. – Arun George

3 Answers

0
votes

Since you are getting back a an error code from APNS, the connection should be dropped at that point and APNS will ignore everything after the error. When you receive an error back, the identifier is the identifier you are currently using a random number for.

There's no easy solution here -- you have to rearchitect what you have so that when you receive the error, you can figure out everything after that point and resend -- I'd recommend using a sequential number for the Identifier and then storing the packets in a queue that you purge periodically (you have to keep them around for say 30 seconds to guarantee that Apple Accepted them).

1
votes

It looks like you are writing a single notification to bao, so why do you expect it to push multiple alerts? If you want to push multiple alerts, you have to repeat that sequence of bytes that you write into bao multiple times.

1
votes

The command 2 and the frame data length applies to each message. If you send multiple messages in one connection, then for each message: send command 2, the message's frame data length, and the 5 parts (token, payload, id, expiry, priority)