Loading external files in PHP the better way

Posted December 6th, 2011 • 2 min read

Sometimes you run into "weird behavior" when using file_get_contents in your code when retrieving external data. I noticed this for instance when accessing the Facebook Graph API the other day. When using file_get_contents the results were so much different than when using cUrl.

Sometimes even, it is disabled on your host for security reasons. So i'm making it a habbit to run everything through cUrl instead. Not just to get the "actual results", but also since it's a lot faster.

Faster you say?

Indeed! Take this benchmark for instance, file_get_contents vs curl on google.com:

[1] => Array   // 1 request to google.com
(
    [FGC] =>  0.4955058 // 38.88% slower
    [CURL] => 0.3582108
)
[5] => Array   // 5 requests to google.com
(
    [FGC] =>  2.2415568 // 24.44% slower
    [CURL] => 1.7973249
)
[10] => Array  // 10 requests to google.com
(
    [FGC] =>  4.7877922 // 29.46% slower
    [CURL] => 3.6951289
)
[25] => Array  // 25 requests to google.com
(
    [FGC] =>  10.932404 // 10.18% slower
    [CURL] => 9.9168329
)
[50] => Array  // 50 requests to google.com
(
    [FGC] =>  22.535982 // 24.74% slower
    [CURL] => 18.068931
)
[100] => Array // 100 requests to google.com
(
    [FGC] =>  44.685283 // 18.57% slower
    [CURL] => 37.688820
)

Sure, it might not seem that big a difference. But imagine loading an external file being a big part of your (heavily) used application.

Got an example ?

Sure, no worries. Rather than calling:

$data = file_get_contents("http://whatever.com/sheep.jpg");

you could do:

<?php
function loadFile($url) {
  $ch = curl_init();

  curl_setopt($ch, CURLOPT_HEADER, 0);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
  curl_setopt($ch, CURLOPT_URL, $url);

  $data = curl_exec($ch);
  curl_close($ch);

  return $data;
}

$data = loadFile("http://whatever.com/sheep.jpg");

And you're done.

Thoughts?

Anyone else experiencing different results between cUrl and the builtin function? I've been googling what could cause this, but so far nothing conclusive.