root / pykota / trunk / pykota / accounters / stupid.py @ 995

# PyKota
#
# 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 1.2  2003/04/30 13:40:47  jalet
# Small fix
#
# Revision 1.1  2003/04/30 13:36:40  jalet
# Stupid accounting method was added.
#
#
#

import sys
import tempfile
from pykota.accounter import AccounterBase, PyKotaAccounterError

class Accounter(AccounterBase) :
    def doAccounting(self, printerid, userid) :
        """Does print accounting by stupidly counting the 'showpage' postscript instructions in the document.
        
           This method is essentially unreliable, but shows how to create a simple accounter.
        """
        # first we log a message because using this accounting method is not recommended.
        self.filter.logger.log_message(_("Using the 'stupid' accounting method is unreliable."), "warn")
        
        # get the job size    
        jobsize = self.getJobSize()
            
        # get last job information for this printer
        pgc = self.filter.storage.getPrinterPageCounter(printerid)    
        if pgc is None :
            # The printer hasn't been used yet, from PyKota's point of view
            counterbeforejob = 0
        else :    
            # get last job size and page counter from Quota Storage
            # Last lifetime page counter before actual job is 
            # last page counter + last job size
            counterbeforejob = (pgc["pagecounter"] or 0) + (pgc["jobsize"] or 0)
            
        # Is the current user allowed to print at all ?
        action = self.filter.warnUserPQuota(self.filter.username, self.filter.printername)
        
        # update the quota for the current user on this printer, if allowed to print
        if action == "DENY" :
            jobsize = 0
        else :    
            self.filter.storage.updateUserPQuota(userid, printerid, jobsize)
        
        # adds the current job to history    
        self.filter.storage.addJobToHistory(self.filter.jobid, self.filter.storage.getUserId(self.filter.username), printerid, counterbeforejob, action, jobsize)
            
        return action
        
    def getJobSize(self) :    
        """Computes the job size and return its value.
        
           THIS METHOD IS COMPLETELY UNRELIABLE BUT SERVES AS AN EXAMPLE.
        """
        temporary = None    
        if self.filter.inputfile is None :    
            infile = sys.stdin
            # we will have to duplicate our standard input
            temporary = tempfile.TemporaryFile()
        else :    
            infile = open(self.filter.inputfile, "rb")
            
        pagecount = 0
        for line in infile.xreadlines() :
            if line.startswith("showpage") :
                pagecount += 1
            if temporary is not None :    
                temporary.write(line)    
                
        if temporary is not None :    
            # this is a copy of our previous standard input
            # flush, then rewind
            temporary.flush()
            temporary.seek(0, 0)
            # our temporary file will be used later if the
            # job is allowed.
            self.filter.inputfile = temporary
        else :
            infile.close()
            
        return pagecount