gistfile1.php

<?php

//Expected value of the payment in satoshi
$real_value = 10000;

$real_secret = 'ZzsMLGKe162CfA5EcG6j';
$invoice_id = $_GET['invoice_id'];
$transaction_hash = $_GET['transaction_hash'];
$input_transaction_hash = $_GET['input_transaction_hash'];
$input_address = $_GET['input_address'];
$value_in_satoshi = $_GET['value'];
$value_in_btc = $value_in_satoshi / 100000000;
$my_bitcoin_address = "1Pqh1kXjMVa8KvSJFg9DoUoKz9G1kNiYvo";
$secret = $_GET['secret'];

//Check the secret passed to the create method is equal
if ($real_secret != $secret) {
  return;
}

//Commented out to test, uncomment when live
if ($_GET['test'] == true) {
	return;
}

//Check the address is our address
if ($_GET['destination_address'] != $my_bitcoin_address)
	return;

try {
  //Open the database - EDIT THIS TO CONNECT TO YOUR DB
	$db = new PDO('mysql:host=localhost;dbname=test', 'root', '');
} catch(Exception $e) {
	die($error);
}

//Get the amount received from this transaction
$amount_validated = file_get_contents('https://blockchain.info/q/txresult/' . $input_transaction_hash . '/' . $input_address);

//Validate the callback is passing the correct amount.
if ($amount_validated < $value_in_satoshi || $real_value < $value_in_satoshi)
	return;

//Assert that 3 or more confirmations have been recieved, quit script execution if not
if ($_GET['confirmations'] < 3)
	return;

//Mark the invoice as paid
$stmt = $db->prepare("UPDATE invoices SET paid=? WHERE id=?");
$query = $stmt->execute(array(1, $invoice_id));

//Send OK back to blockchain.info
if($query) {
	echo "*ok*";
}