GCM android PHP android push notification

Question

my problem has to do with android push notification using PHP curl. The thing is that I send one push notifications to my android devices, but the problem is that a few of my devices get that notification more than once, sometimes 20 times, while some get them only once, hence ruling out fault with the app. I really don't know what the problem could be. Thanks for the anticipated response/solution. Please see push code below

function googlePush($DevID, $Message , $id)
{
// Set POST variables
$url = 'https://android.googleapis.com/gcm/send';
//  static $a=1;
    $DeviceID = array($DevID);
$Message = array("MSG" => $Message, "MSGCNT" => $Message, "message" => $Message, "id" => $id);

$fields = array(
    'registration_ids' => $DeviceID,
    'data' => $Message,
);

$headers = array(
    'Authorization: key=' . 'xxxxxxxxxxxxxxxxxxxxxxxx',
    'Content-Type: application/json'
);
// Open connection
$ch = curl_init();

// Set the url, number of POST vars, POST data
curl_setopt($ch, CURLOPT_URL, $url);

curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    //additions
    curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
    curl_setopt($ch, CURLOPT_FRESH_CONNECT, 1);

// Disabling SSL Certificate support temporarly
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields));

// Execute post
$result = curl_exec($ch);

if ($result === FALSE) {
    die('Curl failed: ' . curl_error($ch));
}

    unset($DeviceID);

// Close connection
    var_dump($result);
curl_close($ch);

}

var dump of result is shown below, I also noticed that some registration_id have the same values

    **********string** '{"multicast_id":8672106836162339205,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxxxxxxxxxxxx","message_id":"0:1393854839483681%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":8498502225166328169,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxxxxxxxxx","message_id":"0:1393854840250166%eee44707f9fd7ecd"}]}' (length=326)


    **string** '{"multicast_id":7302855159132255364,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854840859779%eee44707f9fd7ecd"}]}' (length=143)


    **string** '{"multicast_id":6882780021901998797,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxxxx","message_id":"0:1393854841511331%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":8381589117174890484,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxx","message_id":"0:1393854842128271%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":6847925128400811155,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854842760280%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":7903592410326185172,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxxxxx","message_id":"0:1393854843468783%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":5431281358827461125,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxx","message_id":"0:1393854844108856%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":6242320368959177697,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854844708476%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":6289135300645883957,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854845368752%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":8065775041092982406,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854846007304%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":5796390289718372097,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854846610566%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":8805706816500517785,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxx","message_id":"0:1393854847269971%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":7983336428405472483,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxx","message_id":"0:1393854847888947%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":6228808030640727875,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxxx","message_id":"0:1393854848530967%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":5551712224296927538,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854849250561%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":7677859595454701121,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854849828922%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":4797333817540136724,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxx","message_id":"0:1393854850529846%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":6508223386232436892,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854851209242%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":4773533719835572015,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxx","message_id":"0:1393854851828127%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":5409507279769055411,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxx","message_id":"0:1393854852488533%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":5694677433969852727,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854853131499%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":6750411477469821632,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxx","message_id":"0:1393854853749992%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":4725663028894725199,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854854358521%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":6714161557242774959,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854854967476%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":7546061721250672776,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854855589308%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":4889453422658966187,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854856248256%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":6177254519903698994,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854856849541%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":5057079171295055438,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854857489730%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":9157325687626306713,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854858127816%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":7796618069469674709,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854858748602%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":8051599406708181530,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxxxxx","message_id":"0:1393854859437798%eee44707f9fd7ecd"}]}' (length=326)

    **string** '{"multicast_id":8240272655734048325,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854860088449%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":7266159540819274423,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854860707600%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":4888209323517106512,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854861327433%eee44707f9fd7ecd"}]}' (length=143)

    **string** 
'{"multicast_id":8322636158677230100,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854861950247%eee44707f9fd7ecd"}]}' (length=143)

    **string** '{"multicast_id":5078649048024494474,"success":1,"failure":0,"canonical_ids":0,"results":[{"message_id":"0:1393854862548844%eee44707f9fd7ecd"}]}' (length=143)********

Answer 1

You should handle the returned canonical registration IDs.

For example, consider the following response you got (and your question contains 19 such responses with "canonical_ids":1 ) :

string '{"multicast_id":7546061721250672776,"success":1,"failure":0,"canonical_ids":1,"results":[{"registration_id":"xxxxx","message_id":"0:1393854855589308%eee44707f9fd7ecd"}]}' (length=326)

It means that you used an old registration ID to send a notification to a device that already has a newer registration ID. If you also sent a notification using the new registration ID (the one specified in the registration_id parameter of the response, that would explain the device getting that notification twice.

Whenever you get a response with a canonical registration ID, you should replace in your DB the old registration ID (the one you used to send the notification) with the canonical registration ID specified in the response (or simply delete the old registration ID if you already have the canonical registration ID in your DB).

Answer 2

As far as i can see your code doesn't send the notification more then once. You could perhaps try to log every send push notification to see if curl is really giving you the headache.

if ($result === FALSE) {
    die('Curl failed: ' . curl_error($ch));
} else {
    // Store the exact time and $deviceID in a table or file for logging purpose
}