cURL无法从运行Varnish Cache的服务器下载图像文件

Question

I have the following PHP script that works perfectly 99% of the time. But it will not download an image from this one server which I think is running Varnish Cache.

<?php

$imglink = 'http://www.dirtrider.com/wp-content/uploads/2014/10/WD-10_1_14-001.jpg';

$ch = curl_init($imglink);
$fp = fopen('/home/path/www/tmp/test.jpg', "w");

curl_setopt($ch, CURLOPT_FILE, $fp);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_TIMEOUT, 5);

curl_exec($ch);

fclose($fp);

Answer 1

You get a 403 Forbidden error if you use CURL to load that image. You can work around this error very easily. Just add an alternate user agent for your CURL request:

curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);

And et voila! It works like a charm. Seems like Varnishe Cache blocks CURL requests which use a CURL default user agent.