IOS receipt validation error 21002

Question

I\'m trying to use receipt validation with my server side. Everything is ok, but sometimes I see strange: 10 times validation is OK, but on 11 i get 21002 error. I dont know

Answer 1

The Receipt Data is already base64 encoded. Refer to Receipt Validation Programming Guide

$receipt_data = "MII.................KY\/6oc9w==";

$data = "{\"receipt-data\":\"$receipt_data\"}";

$url = "https://buy.itunes.apple.com/verifyReceipt";        // if use this to test sandbox will return "{"status":21007}"
//$url = "https://sandbox.itunes.apple.com/verifyReceipt";  // for sandbox

var_dump(post($url,$data));

function post($url, $data, $headerArray = array())
{
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST,FALSE);
    curl_setopt($curl, CURLOPT_POST, 1);
    curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    if (array() === $headerArray)
        curl_setopt($curl, CURLOPT_HTTPHEADER,["Content-type:application/json;charset='utf-8'","Accept:application/json"]);

    $output = curl_exec($curl);
    curl_close($curl);
    return $output;
}