root / pykota / trunk / bin / pykota @ 975

#! /usr/bin/env python

# PyKota accounting filter
#
# PyKota - Print Quotas for CUPS and LPRng
#
# (c) 2003 Jerome Alet <alet@librelogiciel.com>
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
#
# $Id$
#
# $Log$
# Revision 1.30  2003/04/29 22:03:38  jalet
# Better error handling.
#
# Revision 1.29  2003/04/29 18:37:54  jalet
# Pluggable accounting methods (actually doesn't support external scripts)
#
# Revision 1.28  2003/04/26 08:41:24  jalet
# Small code reorganisation (UNTESTED) to allow pluggable accounting
# methods in the future.
#
# Revision 1.27  2003/04/25 09:23:47  jalet
# Debug message passed through !
#
# Revision 1.26  2003/04/25 08:23:23  jalet
# Multiple tries to get the printer's internal page counter, waits for
# one minute maximum for the printer to warm up, actually.
#
# Revision 1.25  2003/04/24 11:53:48  jalet
# Default policy for unknown users/groups is to DENY printing instead
# of the previous default to ALLOW printing. This is to solve an accuracy
# problem. If you set the policy to ALLOW, jobs printed by in nexistant user
# (from PyKota's POV) will be charged to the next user who prints on the
# same printer.
#
# Revision 1.24  2003/04/23 22:13:56  jalet
# Preliminary support for LPRng added BUT STILL UNTESTED.
#
# Revision 1.23  2003/04/15 11:30:57  jalet
# More work done on money print charging.
# Minor bugs corrected.
# All tools now access to the storage as priviledged users, repykota excepted.
#
# Revision 1.22  2003/04/15 11:09:04  jalet
# Small bug was fixed when a printer was never used and its internal
# page counter is not accessible.
#
# Revision 1.21  2003/04/12 17:20:14  jalet
# Better formula for HP workaround
#
# Revision 1.20  2003/04/12 16:58:28  jalet
# The workaround for HP printers was not correct, and there's probably no
# correct way to workaround the problem because we can't save the internal
# page counter in real time. The last job's size is unconditionnally set to
# 5 pages in this case.
#
# Revision 1.19  2003/04/11 08:56:49  jalet
# Comment
#
# Revision 1.18  2003/04/11 08:50:39  jalet
# Workaround for the HP "feature" of saving the page counter to NVRAM
# only every time 10 new pages are printed...
# Workaround for printers with volatile page counters.
#
# Revision 1.17  2003/04/10 21:47:20  jalet
# Job history added. Upgrade script neutralized for now !
#
# Revision 1.16  2003/04/08 20:38:08  jalet
# The last job Id is saved now for each printer, this will probably
# allow other accounting methods in the future.
#
# Revision 1.15  2003/03/29 13:45:27  jalet
# GPL paragraphs were incorrectly (from memory) copied into the sources.
# Two README files were added.
# Upgrade script for PostgreSQL pre 1.01 schema was added.
#
# Revision 1.14  2003/03/07 22:16:57  jalet
# Algorithmically incorrect : last user quota wasn't updated if current
# user wasn't allowed to print.
#
# Revision 1.13  2003/02/27 23:59:28  jalet
# Stupid bug wrt exception handlingand value conversion
#
# Revision 1.12  2003/02/27 23:48:41  jalet
# Correctly maps PyKota's log levels to syslog log levels
#
# Revision 1.11  2003/02/27 22:55:20  jalet
# WARN log priority doesn't exist.
#
# Revision 1.10  2003/02/27 22:43:21  jalet
# Missing import
#
# Revision 1.9  2003/02/27 22:40:26  jalet
# Correctly handles cases where the printer is off.
#
# Revision 1.8  2003/02/09 12:56:53  jalet
# Internationalization begins...
#
# Revision 1.7  2003/02/07 10:23:48  jalet
# Avoid a possible future name clash
#
# Revision 1.6  2003/02/06 22:54:33  jalet
# warnpykota should be ok
#
# Revision 1.5  2003/02/05 22:45:25  jalet
# Forgotten import
#
# Revision 1.4  2003/02/05 22:42:51  jalet
# Typo
#
# Revision 1.3  2003/02/05 22:38:39  jalet
# Typo
#
# Revision 1.2  2003/02/05 22:16:20  jalet
# DEVICE_URI is undefined outside of CUPS, i.e. for normal command line tools
#
# Revision 1.1  2003/02/05 21:28:17  jalet
# Initial import into CVS
#
#
#

import sys
import os
import time

from pykota.tool import PyKotaTool, PyKotaToolError
from pykota.config import PyKotaConfigError
from pykota.storage import PyKotaStorageError
from pykota.accounter import openAccounter, PyKotaAccounterError

class PyKotaFilter(PyKotaTool) :    
    """Class for the PyKota filter."""
    def __init__(self) :
        PyKotaTool.__init__(self)
        (self.printingsystem, self.printerhostname, self.printername, self.username, self.jobid, self.inputfile) = self.extractInfoFromCupsOrLprng()
        self.accounter = openAccounter(self)
    
    def extractInfoFromCupsOrLprng(self) :    
        """Returns a tuple (printingsystem, printerhostname, printername, username, jobid, filename) depending on the printing system in use (as seen by the print filter).
        
           Returns (None, None, None, None, None, None) if no printing system is recognized.
        """
        # Try to detect CUPS
        if os.environ.has_key("CUPS_SERVERROOT") and os.path.isdir(os.environ.get("CUPS_SERVERROOT", "")) :
            if len(sys.argv) == 7 :
                inputfile = sys.argv[6]
            else :    
                inputfile = None
                
            device_uri = os.environ.get("DEVICE_URI", "")
            # TODO : check this for more complex urls than ipp://myprinter.dot.com:631/printers/lp
            try :
                (backend, destination) = device_uri.split(":", 1) 
            except ValueError :    
                raise PyKotaToolError, "Invalid DEVICE_URI : %s\n" % device_uri
            while destination.startswith("/") :
                destination = destination[1:]
            printerhostname = destination.split("/")[0].split(":")[0]
            return ("CUPS", printerhostname, os.environ.get("PRINTER"), sys.argv[2].strip(), sys.argv[1].strip(), inputfile)
        else :    
            # Try to detect LPRng
            jseen = Jseen = Pseen = nseen = rseen = None
            for arg in sys.argv :
                if arg.startswith("-j") :
                    jseen = arg[2:].strip()
                elif arg.startswith("-J") :    
                    Jseen = arg[2:].strip()
                    if Jseen == "(STDIN)" :
                        Jseen = None
                elif arg.startswith("-n") :     
                    nseen = arg[2:].strip()
                elif arg.startswith("-P") :    
                    Pseen = arg[2:].strip()
                elif arg.startswith("-r") :    
                    rseen = arg[2:].strip()
            if jseen and Pseen and nseen and rseen :        
                return ("LPRNG", rseen, Pseen, nseen, jseen, Jseen)
        return (None, None, None, None, None, None)   # Unknown printing system          
        
    def filterInput(self, inputfile) :
        """Transparent filter."""
        mustclose = 0    
        if inputfile is not None :    
            infile = open(inputfile, "rb")
            mustclose = 1
        else :    
            infile = sys.stdin
        data = infile.read(256*1024)    
        while data :
            sys.stdout.write(data)
            data = infile.read(256*1024)
        if mustclose :    
            infile.close()
            
    def acceptJob(self) :        
        """Returns the exit code needed by the printing backend to accept the job and print it."""
        if self.printingsystem == "CUPS" :
            return 0
        elif self.printingsystem == "LPRNG" :    
            return 0
        else :    
            # UNKNOWN
            return -1
            
    def removeJob(self) :            
        """Returns the exit code needed by the printing backend to refuse the job and remove it."""
        if self.printingsystem == "CUPS" :
            return 1
        elif self.printingsystem == "LPRNG" :    
            return 3
        else :    
            # UNKNOWN
            return -1
            
def main() :    
    """Do it, and do it right !"""
    # Initializes the current tool
    kotafilter = PyKotaFilter()    
    
    #
    # If this is a CUPS filter, we should act and die like a CUPS filter when needed
    if kotafilter.printingsystem == "CUPS" :
        if len(sys.argv) not in (6, 7) :    
            sys.stderr.write("ERROR: %s job-id user title copies options [file]\n" % sys.argv[0])
            return kotafilter.removeJob()
    
    # Get the last page counter and last username from the Quota Storage backend
    printerid = kotafilter.storage.getPrinterId(kotafilter.printername)
    if printerid is None :
        # The printer is unknown from the Quota Storage perspective
        # we let the job pass through, but log a warning message
        kotafilter.logger.log_message(_("Printer %s not registered in the PyKota system") % kotafilter.printername, "warn")
    else :    
        userid = kotafilter.storage.getUserId(kotafilter.username)
        if userid is None :
            # The user is unknown from the Quota Storage perspective
            # Depending on the default policy for this printer, we
            # either let the job pass through or reject it, but we
            # log a message in any case.
            policy = kotafilter.config.getPrinterPolicy(kotafilter.printername)
            if policy == "ALLOW" :
                action = "POLICY_ALLOW"
            else :    
                action = "POLICY_DENY"
            kotafilter.logger.log_message(_("User %s not registered in the PyKota system, applying default policy (%s) for printer %s") % (kotafilter.username, action, kotafilter.printername), "warn")
            if action == "POLICY_DENY" :
                return kotafilter.removeJob()
        else :
            # Now does the accounting and act depending on the result
            action = kotafilter.accounter.doAccounting(printerid, userid)
            
            # if not allowed to print then die, else proceed.
            if action == "DENY" :
                # No, just die cleanly
                return kotafilter.removeJob()
        
    # pass the job untouched to the underlying layer
    kotafilter.filterInput(kotafilter.inputfile)      
    
    return kotafilter.acceptJob()

if __name__ == "__main__" :    
    try :
        retcode = main()
    except (PyKotaToolError, PyKotaConfigError, PyKotaStorageError, PyKotaAccounterError), msg :
        sys.stderr.write("ERROR : PyKota filter failed (%s)\n" % msg)
        sys.stderr.flush()
        retcode = -1
    sys.exit(retcode)