Introduction to PyKota
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This chapter will briefly introduce you to PyKota, and will familiarize
you with this software and its components.
What is PyKota ?
PyKota is a print quota and print accounting software solution
for GNU/Linux and compatible print servers.
PyKota currently supports the
CUPS
Common UNIX Printing System
printing subsystem, although older releases also supported
LPRng.
PyKota is distributed under the terms of the GNU General Public License of the
Free Software Foundation. This means that
you are allowed to use, modify or redistribute its code provided that you respect
the terms of this license.
We believe that despite being a bit rough around the edges sometimes, PyKota
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.
PyKota 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.
PyKota is made of the following components :
Configuration files, which must be placed into the system user
pykota's home directory as defined in /etc/passwd
If your /etc/passwd contains something like
pykota:x:1001:1001:PyKota Admin,,,:/etc/pykota:/bin/sh
then the home directory is /etc/pykota
:
pykotadmin.conf : this file contains sensitive database settings
allowing the PyKota software to modify the
print quota database. This file should be protected and should only be
made readable by the administrators of PyKota
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 PyKota Administrator or not,
so please give particular attention to this file's permissions.
pykota.conf : this is the main configuration file for
PyKota. It contains database settings which
allow the PyKota 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 PyKota,
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 PyKota command line tools.
Either a PostgreSQL, MySQL or SQLite database, or an LDAP
Lightweight Directory Access Protocol
DIT
Directory Information Tree :
PyKota can store its datas into any of these. Support
for other database backends might be added in a future release.
A generic CUPS backend wrapper, named cupspykota :
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 PyKota's
configuration files.
Several command line tools to manage print quotas and accounting. All of these
commands accept the --version and --help
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.
pksetup : to install PyKota in a completely
interactive way, but currently only under Debian and Ubuntu.
pkturnkey : to help you do the initial
configuration and database initialization. This command almost transforms PyKota
into a turn-key solution, hence the name.
pkprinters : to manage printers and printers groups.
pkusers : to manage users and users groups.
edpykota : to manage users' and users groups' print quota entries.
pkbcodes : to manage billing codes.
repykota : to do some basic print quota reporting.
dumpykota : to dump the database's contents in a portable
way. This command can be used to export PyKota's
datas to third party software, like print log analyzers or spreadsheets, and
numerous output formats are supported, like csv and XML
autopykota : to automate the creation of user print accounts on
first print. This command is not meant to be used from the command line, but
instead from pykota.conf's policy directive.
pykosd : to display their remaining credits or
pages to end users. This is an OSD On Screen Display
application which works under the X Window system.
pykotme : to give detailed quotes to end users before they print, 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.
pkbanner : to generate dynamic banner pages when printing.
This command is
not meant to be used from the command line, but
instead from pykota.conf's startingbanner
and endingbanner directives. If you prefer you can use
your own generator of dynamic banner pages or even static banner pages.
warnpykota : to warn users over quota from time to time, for example
from crontab. Users are warned while printing in any case, so
this command is meant to be used as a periodic reminder.
pknotify : a client for the PyKotIcon cross-platform generic network dialog box manager. This
tools allow you to interact with end users at printing time.
pkinvoice : an invoice generator which can create personalized PDF invoices
for your users from their printing history.
pkrefund : a tool with which you can refund print jobs
when there was an accounting problem. It can generate printable receipts
in the PDF format.
Several CGI scripts which constitute PyKota's web interface.
All these scripts behave differently when they are protected with an username and password
compared to when they are not. See pykota/cgi-bin/README for
details.
printquota.cgi : to do basic print quota reports like repykota,
and also to examine the printing history, which is not possible with repykota for now.
dumpykota.cgi : identical to the dumpykota
command line tool, but works from within a web browser.
pykotme.cgi : identical to the pykotme
command line tool, but works from within a web browser.
Several helper scripts and contributed stuff to handle very specific configurations.
Please visit the subdirectories of the pykota/ source directory, and
you may find interesting things...