PHP 从使用 ASP 脚本的远程服务器下载文件

Question

I'm trying to run my php script to download files off a remote server. My script works fine when the remote url is pointing directly to the file, like " http://example.com/files/file.pdf ".

Problem is, most of the files are on a ASP server, and I don't have the url to the file path directly. Instead the ASP server is running a script to download the file. Those urls are like this: " http://example.com/files/GetFile.aspx?Id=2722&Autoresolve=True ".

So when I try reading the file content of the ASP server I get the literal markup of the page instead.

This is my code at the moment:

$url = 'example.com/file.pdf';
$uploadfile = 'myserver.com/file.pdf';
$contents = file_get_contents($url);
$savefile = fopen($uploadfile, 'w');
fwrite($savefile, $contents);
fclose($savefile);

I can't seem to find any examples online for when the target file is being served by a script.

Is this even possible and what do I need to look at?

Answer 1

most likely means that you need to have a cookie session prior to attempting the download. sometimes you must even initiate a download request and get an unique download url prior to actually doing the download. and sometimes you even have to log in prior to doing the actual download.

you can use Fiddler Proxy to look at the download request made by your browser (most browsers (at least FireFox and Chrome) make it difficult to look at file download requests, hence the need for Fiddler proxy, even with the built-in dev tools), look for cookie session ids, or unique-looking tokens, sometimes they're in the cookies (like PHPSESSID), sometimes they're in the url (like /getFile.asp?id=123&token=qawsedrfgvbhnjm ), and sometimes they're in a HTTP header (like X-download-token: awsxdcfgbhn )

.. but since you didn't share the actual website you're trying to download from, nobody here can tell you exactly what your specific website needs.