Json_decode 没有从数组中获取值

Question

I am absolute beginner in PHP, but some years ago I managed to create this simple code which calculates the daily price of copper in Bulgarian leva (BGN)

Unfortunately today I found out that the variable $copper_lv_per_ton is empty and does not return anything

$copper_data = json_decode(file_get_contents('https://www.quandl.com/api/v3/datasets/LME/PR_CU.json?limit=1&api_key=nXWf2HdsDzw6b4LK-moU'), true);
$currency_data = json_decode(file_get_contents('https://openexchangerates.org/api/latest.json?app_id=248e0a098c90432aabd9f17c98f9a030'), true);
$copper_lv_per_ton = $copper_data['dataset']['data'][0][2]*$currency_data['rates']['BGN'];

Thank you for your support!

I am really trying to solve it for hours and cannot find what is going on

Answer 1

The problem appeared from my Joomla website, where I get the variables and used them in a formula without seeing any errors or debug happening.

Then I tried the code in the W3Schools compiler and it was not working again. Then @KIKO Software suggested to not use online compilers for such a thing and put it on my own webserver.

I did so and found out the following error

Then I just changed allow_url_fopen: to ON in PHP Manager (CPANEL) and everything just worked.

Thank you for the support! Wish a lot of health to everybody