php

<?php

$response = array();
include 'db_connect.php';

$db = new DB_CONNECT();
include 'db_config.php';

$con = mysqli_connect(DB_SERVER, DB_USER, DB_PASSWORD, DB_DATABASE) or die(mysqli_error($con));
$result = mysqli_query($con, "SELECT id, username FROM usuario") or die(mysqli_error($con));

if(mysqli_num_rows($result)>0){
$response["usuario"] = array();

while($row = mysqli_fetch_array ($result)){
$product = array();
$product['id'] = $row['id'];
$product['username'] = $row['username'];

array_push($response["usuario"], $product);
}

$response["success"]=1;
echo json_encode($response);

}
else{
$response["success"]=0;
$response["message"]="Nenhum usuario cadastrado";

echo json_encode($response);
}
?>