Why is `file_get_contents()` Failing to Retrieve External URLs on This Server?

File_get_contents Issue with External URLs on Specific Server

Problem:

When using the PHP function file_get_contents() to retrieve the contents of an external URL on a specific server, an empty result is returned. However, the function works correctly when used locally or when accessing internal URLs on the same server.

Possible Cause:

The issue is likely related to a PHP.ini configuration setting.

Solution:

To determine which PHP.ini configuration is causing the problem, follow these steps:

1. Check the allow_url_fopen setting: This setting controls whether PHP can access external URLs through the fopen family of functions. If it is set to Off, file_get_contents() will not be able to retrieve content from external URLs.

   Check the PHP.ini file for the following line:

   allow_url_fopen = Off

   If it is set to Off, change it to On.

2. Check the allow_url_include setting: This setting controls whether PHP can include external URLs in scripts. If it is set to Off, file_get_contents() may not be able to retrieve content from external URLs.

   Check the PHP.ini file for the following line:

   allow_url_include = Off

   If it is set to Off, change it to On.

3. Use an alternative function: If the above settings do not solve the issue, you can use alternative functions to mimic the behavior of file_get_contents(). One such function is curl_init():

   function get_content($URL){
      $ch = curl_init();
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
      curl_setopt($ch, CURLOPT_URL, $URL);
      $data = curl_exec($ch);
      curl_close($ch);
      return $data;
   }
   
   echo get_content('http://example.com');

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