Problems opening URL via proxy

rachelkoh

Hi,

I've seen this problem from previous post and it was resolved by using fsockopen below.

function damnProxy($page, $proxyHost, $proxyPort) {  

    $data = fsockopen($proxyHost, $proxyPort);   

    if(!$data)  {  

        fclose($result);   

        echo "Cannot access ".$page;  

    }   

    else {   

        fputs($data,"GET $page HTTP/1.0\n\n");   

        while(!feof($data)) {  

            $cont=$cont.fread($data,4096);  

        }  

    }  

    fclose($data);  

    return substr($cont,strpos($cont,"\r\n\r\n")+4);  

}  

$slash = damnProxy("http://slashdot.org/slashdot.rdf", "proxy.yourcompany.com", 8080);  

if($slash) {  

    echo $slash;  

}  

else {  

    echo "damned proxy";  

}

Well, I don't quite understand what the code is doing after fsockopen successfully, but I guess it's writing something. What I need is to open the URL that's all. I just want to check if a URL provided is valid.
1) How can I do it?
2) Is there anyway I can get the proxy host and port number by some $_SERVER or some other super global arrays?

Below is my code:

// check URL format
   if (strstr($URL, "http://")===false)
      $new_url = "http://".$URL;

// check URL is valid
   $proxyHost = $myproxyhost;
   $proxyPort = 80;
   $OpenInternetConnection = fsockopen($proxyHost, $proxyPort, $errno, $errstr);   

   echo $errno;
   echo $errstr;
   echo "<br>";
   if (@fopen($URL, "r")) 				
     echo "OK";					
   else				
     echo $URL." is not a valid URL.";

Natty_Dreadlock

hi,

What I need is to open the URL that's all. I just want to check if a URL provided is valid.
1) How can I do it?
2) Is there anyway I can get the proxy host and port number by some $_SERVER or some other super global arrays?

are u behind a proxy server??? then u should know the port number and the proxy host, i guess? if not, ask your provider / check their website.
the function damnProxy($page, $proxyHost, $proxyPort) tries to retrieve the page $page via the $proxyHost using port $proxyPort, so u can use it to check whether some url is valid if u r behind a proxy...
hth

rachelkoh

Hi thanks!
I have the proxy host and number correct. But I still can't fopen the URL.
fopen doesn't work with fsockopen?

Hey, but can I replace fopen($URL, "r") with fgets($URL, 1) ?????

Moonglobe

no. check to see if you have allow_url_fopen on in your php.ini

Natty_Dreadlock

u should also be able to use the function damnProxy($page, $proxyHost, $proxyPort) - i.e. $page = damnProxy("http://test.com", "proxy.home.net", 8080) - just insert the values u got from your provider and it might work.
hth

rachelkoh

allow_url_fopen is on.

I didn't try that because I thought it was reading the whole file on the page. This isn't what I wanted.

Any other ways?

Natty_Dreadlock

the download of the page should be no problem unless u check lots of pages or the existence of large files. if u just wanna check if some file is there, try to replace the GET and use HEAD instead in damnProxy()... might work

rachelkoh

Hi, I've tried the function but it didn't work for me, It echo "http://mail.yahoo.com/?.intl=us is not a valid URL.". HOW COULD IT BE??? There's no error with fsockopen. Wht I have done:

//function damnProxy is under testing 
function damnProxy($page, $proxyHost, $proxyPort) {   

    $data = fsockopen($proxyHost, $proxyPort, $errno, $errstr);    

    if(!$data)  {   

        fclose($result);   

        echo "Problem: ". $errstr;
   		echo "<br>"; 
        echo "Cannot access ".$page;   

    }    

    else {    

        fputs($data,"GET $page HTTP/1.0\n\n");    

        while(!feof($data)) {   

            $cont=$cont.fread($data,4096);   

        }   

    }   

    fclose($data);   

    return substr($cont,strpos($cont,"\r\n\r\n")+4);   

}

   // check URL is valid
	$slash = damnProxy("$eprintsURL", "proxy.dmz.itee.uq.edu.au", 8080);   

	if($slash) 
	{   

    	$title = $HTTP_POST_VARS["title"];
     	$pid=get_projectId($title);
     	if (upload_paper($pid, $eprintsURL, $valid_user))
       		echo "Paper uploaded.";
     	else
      	 	echo "Could not upload paper. ";
   }					
   else				
     echo $eprintsURL." is not a valid URL.";

Natty_Dreadlock

is your code available online? pls post the url so that we can test it...

rachelkoh

Hi Natty_Dreadlock,

Sorry, my fault, it's working now 🙂 Thank you so much for your time.

If possible, can you tell me more about the code?

Why does it write "GET $page HTTP/1.0\n\n" to the file pointer? What does HTTP/1.0 mean?

Secondly, what's the reason for choosing the "4096" length of bytes of data to be read?

Lastly, what exactly does it return?

If you still can bear with me, please give me a hint on why doesn't fopen work?

Natty_Dreadlock

GET is a http-command, i.e. the same command your browser sends to some page when u open the url. u can view the original rfcs, the specification etc on http://www.w3.org/Protocols/Specs.html or search the net for http specification or something like this and u will get lots of information and tutorials on the protocol since it's the most important one for the www.
hth