PHP：获得2个警告和6个通知[关闭]

Question

I need help with 2 warnings and 6 notices.

Notice: Trying to get property of non-object in on line 11

Notice: Trying to get property of non-object in on line 28

Notice: Trying to get property of non-object in on line 29

Notice: Trying to get property of non-object in on line 30

Notice: Trying to get property of non-object in on line 31

Notice: Trying to get property of non-object in on line 33

Warning: PDOStatement::execute(): SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'steamID' cannot be null in on line 34

I'm been trying to fix code for like 4 hours now and I just can't understand what the hell is going on...

<?php
require_once "../config.php";
require_once "../db.php";
if(!isset($_GET['secret']) || $_GET['secret'] != $config['bot_key_add']){
    die("Access denied");
    return;
}

$json = json_decode(file_get_contents("php://input"), false, 512, JSON_BIGINT_AS_STRING);

if((int)$json->userID ==)       
    return;

$weapon = urlencode($json->weapon);
$link = "http://steamcommunity.com/market/priceoverview/?currency=1&appid=730&market_hash_name=".$weapon;
$steam_price = file_get_contents($link);
$item_price = json_decode($steam_price, false, 512, JSON_BIGINT_AS_STRING);
if(empty($item_price) || $item_price->success == false || empty($item_price->median_price))
{
    $price = 400;
}
else 
{
    $price = $item_price->median_price;
    $price = str_replace("&#36;" , "", $price);
    $price = str_replace("$" , "", $price);
    $price = round(str_replace(",",".",$price), 2);
}
$saveWeapon = $pdo->prepare("INSERT INTO `{$config['db_prefix']}users_items` (`steamID`, `classid`, `assetid`, `weapon_name`, `price`, `float`) VALUES (:steamId , :classid , :assetid , :weaponName , :price, :float)");

$saveWeapon->execute([  ":steamId"      => $json->userID,
                        ":classid"      => $json->classid,
                        ":assetid"      => $json->assetid,
                        ":weaponName"   => $json->weapon,
                        ":price"        => $price,
                        ":float"        => $json->color
]);
?>

Answer 1

Basically your file_get_contents("php://input") doesnt return a file object, so rest is failing (all the warnings) due to missing file object. So "file_get_contents" can't open the correct file and steam is answering with error. Rest is a follow up error.

You can avoid this by checking and sanitizing the input to your script and abort if check fail.