require_once the same file multiple time? - php

Question

I have a config file that contain credential information to connect to an API
I include my config file in 2 functions in 2 different file
In the first called function, I have my credential variables but when I call my second function, my credential variables are empty.
index.php
<?php
require_once("./connector/hot/hotelbeds/book.php");
if($_REQUEST['connector'] == 'hotelbeds')
{
require_once("connector/hot/hotelbeds/validate.php");
validate_hotelbeds($_REQUEST);
}
$booking_output = book_hotelbeds($_REQUEST);
?>
validate.php
<?php
function validate_hotelbeds($results)
{
$account = $results['header']['account'];
include_once("./connector/hot/hotelbeds/account_config/$account/config.php");
// $url contain my url
$validate = curl_get($url , $results);
}
?>
book.php
<?php
function book_hotelbeds($results)
{
$account = $results['header']['account'];
include_once("./connector/hot/hotelbeds/account_config/$account/config.php");
// $url is empty
$book = curl_get($url , $results);
}
?>
config.php
<?php
$url = "http://www.websitelink.com";
?>

Answer 1

The first time you require it, the variables will be introduced.
When you require it again from inside a function, the file has already been required so it is ignored.
The variables are outside the scope of the function at this point, so if you have to you would need to access them by declaring them as global.
Perhaps a better idea would be do declare those variables as constants instead, which means they will be available within the function scopes:
$myVariable = 'hello';
define('MY_CONSTANT', 'world');
echo 'Global scope: ', $myVariable, MY_CONSTANT, PHP_EOL; // helloworld
function myFunction()
{
echo 'Function scope: ', $myVariable, MY_CONSTANT, PHP_EOL; // world
}
function myGlobalFunction()
{
global $myVariable;
echo 'Function scope using global: ', $myVariable, MY_CONSTANT, PHP_EOL; // helloworld
}
Example.

Answer 2

Put your include_once("./connector/hot/hotelbeds/account_config/$account/config.php"); into index instead. Then if you wanted to use the var $url you would need a line above stating that you want that global var: global $url;.
Also I suggest changing $url name and change it to constant like: const API_URL = 'website_url'

Answer 3

Functions require_once and include_once include file only on time for one call of script. Because you include files book.php and validate.php in index.php then PHP include config.php only one time.
You can include config.php in index.php and use global directive inside your function.
Or you can just use functions include and require. These functions include one file to script many times - on each call.