root / pykota / trunk / docs / introduction.sgml @ 2527

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<chapter>
  <title id="introduction">Introduction to PyKota</title>
  
  <para>Last modified on $Date$</para>
  
  <para>
    This chapter will briefly introduce you to PyKota, and will familiarize
    you with this software and its components.
  </para>
  
  
  <sect1>
    <title>What is <application>PyKota</application> ?</title>
    
    <para>
      <application>PyKota</application> is a print quota and print accounting software solution
      for GNU/Linux and compatible print servers.
    </para>
    
    <para>
      PyKota currently supports the
      <ulink url="http://www.cups.org"><application>CUPS</application></ulink>
      <footnote><para>Common UNIX Printing System</para></footnote>
      printing subsystem, although older releases also supported 
      <ulink url="http://lprng.sourceforge.net"><application>LPRng</application></ulink>.
    </para>
    
    <para>
      PyKota is distributed under the terms of the GNU General Public License of the
      <ulink url="http://www.fsf.org">Free Software Foundation</ulink>. This means that
      you are allowed to use, modify or redistribute its code provided that you respect
      the terms of this license.
    </para>
    
    <para>
      We believe that despite being a bit rough around the edges sometimes, <application>PyKota</application>
      offers an unmatched flexibility and probably all you want to do with a print quota software is
      either already included, easily scriptable with a few lines of shell scripting, or planned
      for the next release.
    </para>
    
    <para>
      <application>PyKota</application> is however a somewhat complex piece of software, and installing
      it will mandate that you also install several dependencies beforehand, as you'll see in the
      next chapter.
    </para>
    
    <para>
      <application>PyKota</application> is made of the following components :
      <itemizedlist>
        <listitem>
          <para>
            Configuration files, which must be placed into the system user
            <literal>pykota</literal>'s home directory :
            <itemizedlist>
              <listitem>
                <para>
                  <filename>pykotadmin.conf</filename> : this file contains sensitive database settings
                  allowing the <application>PyKota</application> software to modify the
                  print quota database. This file should be protected and should only be
                  made readable by the administrators of <application>PyKota</application>
                  and the system user the printing subsystem is running as.
                  The possibility for a particular user to read this file determines if
                  this user is a <application>PyKota</application> Administrator or not,
                  so please give particular attention to this file's permissions.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pykota.conf</filename> : this is the main configuration file for 
                  <application>PyKota</application>. It contains database settings which
                  allow the <application>PyKota</application> software to access to the print
                  quota database in readonly mode, as well as global and print queue specific
                  configuration directives. With a properly configured <application>PyKota</application>, 
                  letting normal users read this file is safe
                  excepted where you want to forbid users to read other users' print quota
                  information. However if you're not confident about your database settings,
                  it's better to not let normal users read this file. This way they can't even
                  use any of the <application>PyKota</application> command line tools.
                </para>
              </listitem>  
            </itemizedlist>
          </para>
        </listitem>  
        <listitem>
          <para>
            Either a <application>PostgreSQL</application> database, or an <acronym>LDAP</acronym>
            <footnote><para>Lightweight Directory Access Protocol</para></footnote>
            <acronym>DIT</acronym>
            <footnote><para>Directory Information Tree</para></footnote> :
            <application>PyKota</application> can store its datas into any of these. Support
            for other database backends  might be added in a future release.
          </para>
        </listitem>  
        <listitem>
          <para>
            A generic <acronym>CUPS</acronym> backend wrapper, named <filename>cupspykota</filename> :
            this software captures all print jobs passing through the print queues it manages,
            and does the accounting and quota checking. It can reject print jobs in a number
            of circumstances like the user being over quota, and interact with the end user through the use of external
            commands or shell scripts. This software is written in such a manner than system
            administrators can plug their own scripts at the most strategic points of the 
            printing process, through specific directives that you put in <application>PyKota</application>'s
            configuration files.
          </para>
        </listitem>  
        <listitem>
          <para>
            Several command line tools to manage print quotas and accounting. All of these
            commands accept the <literal>--version</literal> and <literal>--help</literal>
            command line switches, and all have a manual page. Many manual pages are available
            in several native languages and contain usage examples. Some commands have many
            options and switches, so please read their help carefully.
            <itemizedlist>
              <listitem>
                <para>
                  <filename>pkturnkey</filename> : to help you do the initial
                  configuration and database initialization. This command almost transforms <application>PyKota</application>
                  into a turn-key solution, hence the name.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pkprinters</filename> : to manage printers and printers groups.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>edpykota</filename> : to manage users, users groups and quotas.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pkbcodes</filename> : to manage billing codes.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>repykota</filename> : to do some basic print quota reporting.
                </para>
              </listitem>  
              <listitem>
                <para>
                   <filename>dumpykota</filename> : to dump the database's contents in a portable
                   way. This command can be used to export <application>PyKota</application>'s
                   datas to third party software, like print log analyzers or spreadsheets, and
                   numerous output formats are supported.
                </para>
              </listitem>  
              <listitem>
                <para>
                   <filename>autopykota</filename> : to automate the creation of user accounts on
                   first print. This command is not meant to be used from the command line, but
                   instead from <filename>pykota.conf</filename>'s <literal>policy</literal> directive.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pykosd</filename> : an X Window application to display their remaining credits or
                  pages to end users.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pykotme</filename> : to help end user obtain quotes before printing, this way
                  they know in advance how much a print job will cost to them and can decide to route it to
                  a less costly printer.
                </para>
              </listitem>  
              <listitem>
                <para>
                   <filename>pkbanner</filename> : to generate dynamic banner pages when printing.
                   This command is
                   not meant to be used from the command line, but
                   instead from <filename>pykota.conf</filename>'s <literal>startingbanner</literal> 
                   and <literal>endingbanner</literal> directives. If you prefer you can use
                   your own generator of dynamic banner pages or even static banner pages.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>warnpykota</filename> : to warn users over quota from time to time, for example
                  from <filename>crontab</filename>. Users are warned while printing in any case, so
                  this command is meant to be used as a periodic reminder.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pkmail</filename> : to let users obtain their print quota situation by email.
                  In the future other functionnalities will be added.
                  This command is not meant to be used from the command line, but
                  instead as a pipe from your mail server's <filename>/etc/aliases</filename> file.
                </para>
              </listitem>  
            </itemizedlist>
          </para>
        </listitem>  
        <listitem>
          <para>
            Several <acronym>CGI</acronym> scripts which constitute <application>PyKota</application>'s web interface.
            All these scripts behave differently when they are protected with an username and password
            compared to when they are not. See <filename>pykota/cgi-bin/README</filename> for
            details.
            <itemizedlist>
              <listitem>
                <para>
                  <filename>printquota.cgi</filename> : to do basic print quota reports like repykota, 
                  and also to examine the printing history, which is not possible with repykota for now.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>dumpykota.cgi</filename> : identical to the <filename>dumpykota</filename>
                  command line tool, but works over the web.
                </para>
              </listitem>  
              <listitem>
                <para>
                  <filename>pykotme.cgi</filename> : identical to the <filename>pykotme</filename>
                  command line tool, but works over the web.
                </para>
              </listitem>  
            </itemizedlist>
          </para>
        </listitem>  
        <listitem>
          <para>
            Several helper scripts and contributed stuff to help manage particular configurations.
            Please visit the subdirectories of the <filename>pykota/</filename> directory, and
            you may find interesting things...
          </para>
        </listitem>  
      </itemizedlist>
    </para>
    
  </sect1>  
  
</chapter>