Using Authentication And file_get_contents()

Using file_get_contents() to fetch the contents of a file is quite a common practice. This might be just to get the contents of a text file or to get the ImageCache module in Drupal to pre-cache images. The file_get_contents() function can get a local or remote file and is usually run like this.

$data = file_get_contents($url);

However, when trying to use this function to communicate with an authenticated server you will see the following error appearing.

Warning: file_get_contents(http://www.example.com/test.php): failed to open stream: HTTP request failed! 
HTTP/1.1 401 Authorization Required in test.php on line 4

To get around this issue you will need to pass a third parameter to the file_get_contents() function that causes the function to use a context. This context will pass an additional Authorization header to the server and is created through a function called stream_context_create(). Here is all the code you need to use file_get_contents() in an authenticated manner.

$username = 'username';
$password = 'password';
 
$context = stream_context_create(array(
    'http' => array(
        'header'  => "Authorization: Basic " . base64_encode("$username:$password")
    )
));
$data = file_get_contents($url, false, $context);

The second parameter is for the addition of a flag and is skipped here by using a null value, but false is also applicable. For more information about what flags are available see the file_get_contents() page on the PHP manual.