Tutorial: Storing files and retrieving them as compressed files, using PHP & MySQL.

Replies

• 

  PraveenKumar Purushothaman

  Next part is the storing files. All the files (jquery.js, mootools.js, scriptaculous.js, prototypejs.js, and lightbox2.js) are stored under "plugins" folder. You should already have a code for the users to make it to the selection of the files. We use a session & user management here. If you see the second table, it tracks the downloads with their usernames. We get the username from a session variable.
  
  Now there should be a dedicated folder for creating the zip file, with the permissions set to 777 (*nix) or write permissions (Windows). Lets have the name of the folder as "downloads".
  The final part is the writing of the core logic, which creates the compressed files for downloads.
  
  Let us now write the core PHP function, which creates the zip files.

  function create_zip($files = array(), $destination = '', $overwrite = false)
{
    //if the zip file already exists and overwrite is false, return false
    if (file_exists($destination) && !$overwrite)
    {
        return false;
    }
    //vars
    $valid_files = array();
    //if files were passed in...
    if (is_array($files))
    {
        //cycle through each file
        foreach($files as $file)
        {
            //make sure the file exists
            if (file_exists($file))
            {
                $valid_files[] = $file;
            }
        }
    }
    //if we have good files...
    if (count($valid_files))
    {
        //create the archive
        $zip = new ZipArchive();
        if ($zip - > open($destination, $overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true)
        {
            return false;
        }
        //add the files
        foreach($valid_files as $file)
        {
            $zip - > addFile($file, $file);
        }
        //debug
        //echo 'The zip archive contains ',$zip->numFiles,' files with a status of ',$zip->status;
        //close the zip -- done!
        $zip - > close();
 
        //check to make sure the file exists
        return file_exists($destination);
    }
    else
    {
        return false;
    }
}
• 

  PraveenKumar Purushothaman

  After this, you have to include the file in your application, by either putting it on the top or including it in a separate file named functions.inc or something. I am using the second method as I have grouped all the functions in a single file. My code now as follows:

  include("db.inc");
include("functions.inc");
// Since the user is logged in, the username is stored in $_SESSION["username"], which is "Praveen".
$res = mysql_query("SELECT `filename` from `download`, `plugins` WHERE `plugins`.`id`=`download`.`pluginid` AND `username`='" . $_SESSION["username"] . "'");
while($dat = mysql_fetch_array($res))
    $files[] = $dat[0];
create_zip($files, $locationFilename, true);
echo '[url='.$locationFilename.'] Click here to download PDFs [/url]';

  That's it! The link to the freshly created zip file is displayed! 😀 Enjoy! If you have any queries, post them in this thread and I will do my best to answer them.
• 

  PraveenKumar Purushothaman

  #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-#, #-Link-Snipped-# Did you guys check this out? Try it out and do say... 😀