Can't set permission for flow3 in Ubuntu

I'm newbie to flow3. Actually, I have downloaded the flow3 package and place it in my server directory in my local Ubuntu machine. But it demands me to provide permissions to the flow3 directory. the syntax is

$ sudo ./flow3 flow3:core:setfilepermissions johndoe wwwuser wwwgroup

which johndoe is the username, wwuser is the username of the web server, and wwwgroup is the web server's group.

Unfortunately, I have no idea how to know what is my web server username and the web server group.

please refer to this link to see more.

Solution

Thanks guy for taking a review on my question. After a tough searching on the Internet and ask my friend, I can use the command:

$ sudo ./flow3 flow3:core:setfilepermissions vannkorn www-data www-data

Then it requires me to join the web server's group. So I used this command:

$ sudo usermod -a -G www-data vannkorn

After that I need to provide permission 777 on my flow3 directory:

$ sudo chmod 777 -R /home/vannkorn/dev/flow3/

After that, the very most important thing, is the add the document root in my virtual host.

<VirtualHost *:80>
    DocumentRoot /home/vannkorn/dev/flow3/web/
    ServerName flow3_learning

    <Directory />
      Options FollowSymLinks
      AllowOverride All
      Order allow,deny
      allow from all
    </Directory>
</VirtualHost>

Anyway, thanks u guy for taking a look on this post, and I hope this would be helpful for others.