Question

My web server is running on one server, and the data fetching is running on another server. My code will try copy a remote file and store it in my local path. The remote location is, for example, /home/testUser/remoteData.xml. I know the server IP address and hostname. How can I construct the path to fill in the remotePath?

#remotePath is the path to the file on the network
public function __construct()
{
   $this->localPath="currentData.xml";
   $this->remotePath="a remote path";
}

#this will attempt to make a copy from that network file and store it locally
private function fetchServer()
{
   if (!(file_exists($this->remotePath)) || (time() - filectime($this->remotePath)) >= 1200)
      return false;
   else
   {  $success = copy($this->remotePath, $this->localPath);
      if($success)
         return true;
      else
         return false;
   }
}

Thank you very much!

Answer 1

If you’re using HTTP, you won’t be able to check the creation time. If you know that it is a small, manageable file, you can use file_get_contents:

 $fl = @file_get_contents( '<stream>' );
 if( !$fl ) return false; // file does not exist remotely
 $ret = @file_put_contents( '<output name>', $fl );// just output it
 return $ret && true; //force it to boolean

If it is a bit larger, you can use the cURL and stream syntax, or you can do something similar to what I did above:

 $fl = @fopen( '<stream>' );
 if( !$fl ) return false;// file does not exist remotely
 $out = @fopen( '<local file>', 'w');
 if( !$out ) return false;
 while($data = fread($fl)){fwrite($out,$data);}
 fclose($out);
 return true;

Of course, all situations you will have to download the file to a local version and then do some form of checksum to see if there is a difference.

EDIT

---

You just mentioned that timestamp is a requirement but that you also have SSH. If you have SSH, then you might be able to use SFTP (which is something that piggy-backs off of SSH). I have used phpseclib for several projects and, while not perfect (it is in PHP4 and it does not truly tunnel for SSH), it is a very impressive library nevertheless. Look at the networking part of the manual and (if I remember) it will give you more than enough to do what you’re asking for.