#! /usr/bin/python 
#
# analog: Remote logging manager for the Red Hat Installer
#
# Copyright (C) 2010
# Red Hat, Inc.  All rights reserved.
#
# 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, see <http://www.gnu.org/licenses/>.
#
# Author: Ales Kozumplik <akozumpl@redhat.com>
#

import getpass
import errno
import optparse
import os
import os.path
import signal
import sys

DEFAULT_PORT = 6080
DEFAULT_ANALOG_DIR = '.analog'
USAGE = "%prog [options] <log directory root>"
HINT = "/sbin/rsyslogd -c 4 -f %(conf)s -i %(pid)s"
PID_LOCATION = "/tmp/%(username)s/rsyslogd_%(port)s.pid"

RSYSLOG_TEMPLATE ="""
#### MODULES ####
# Provides TCP syslog reception
$ModLoad imtcp.so  
$InputTCPServerRun %(port)s

#### GLOBAL DIRECTIVES ####

# Use default timestamp format
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat

# File syncing capability is disabled by default. This feature is usually not required, 
# not useful and an extreme performance hit
#$ActionFileEnableSync on


#### RULES ####

$template anaconda_tty4, "%%timestamp:8:$:date-rfc3164%%,%%timestamp:1:3:date-subseconds%% %%syslogseverity-text:::uppercase%% %%programname%%:%%msg%%\\n"
$template anaconda_debug, "%%syslogfacility-text%%|%%hostname%%|%%syslogseverity-text%%|%%syslogtag%%|%%msg%%\\n"
$template anaconda_syslog, "%%timestamp:8:$:date-rfc3164%%,%%timestamp:1:3:date-subseconds%% %%syslogseverity-text:::uppercase%% %%programname%%:%%msg%%\\n"

$template path_syslog, "%(directory)s/%%FROMHOST-IP%%/syslog
$template path_anaconda, "%(directory)s/%%FROMHOST-IP%%/anaconda.log"
$template path_program, "%(directory)s/%%FROMHOST-IP%%/program.log"
$template path_storage, "%(directory)s/%%FROMHOST-IP%%/storage.log"
$template path_sysimage, "%(directory)s/%%FROMHOST-IP%%/install.log.syslog"

*.*                                                  %(directory)s/debug_all.log;anaconda_debug

kern.*;\\
daemon.*                                             ?path_syslog;anaconda_syslog

:programname, contains, "loader"                     ?path_anaconda;anaconda_syslog
:programname, contains, "anaconda"                   ?path_anaconda;anaconda_syslog
:programname, contains, "program"                    ?path_program;anaconda_syslog
:programname, contains, "storage"                    ?path_storage;anaconda_syslog
:hostname, contains, "sysimage"                      ?path_sysimage;anaconda_syslog

# discard those that we logged
:programname, contains, "rsyslogd"                   ~
:programname, contains, "loader"                     ~
:programname, contains, "anaconda"                   ~
:programname, contains, "program"                    ~
:programname, contains, "storage"                    ~
:hostname, contains, "sysimage"                      ~
kern.*                                               ~
daemon.*                                             ~
# dump the rest
*.*                                                  %(directory)s/debug_unknown_source.log;anaconda_debug

"""

# option parsing
class OptParserError(Exception):
    def __str__(self):
        return self.args[0]

    @property
    def parser(self):
        return self.args[1]
    
def get_opts():
    parser = optparse.OptionParser(usage=USAGE,
                                   add_help_option=False)
    parser.add_option ('-h', '--help', action="callback", callback=help_and_exit,
                       help="Display this help")
    parser.add_option ('-p', type="int", dest="port", 
                       default=DEFAULT_PORT, 
                       help="TCP port the rsyslog daemon will listen on")
    parser.add_option ('-o', type="string", dest="output", 
                       default=None, 
                       help="Output file")
    parser.add_option ('-s', action="store_true", dest="stdout",
                       default=False, 
                       help="Generate bash command to run rsyslogd on stdout (only valid when -o is also specified)")
    (options, args) = parser.parse_args()
    if len(args) < 1:
        raise OptParserError("no log root directory given", parser)
    if options.stdout and not options.output:
        raise OptParserError("-s only valid with -o", parser)
    options.log_root = args[0]
    args = args[1:]
    return (options, args)

def help_and_exit(option, opt, value, parser):
    parser.print_help()
    sys.exit(0)

def generate_rsyslog_config(port, directory):
    values = {
        "directory" : directory,
        "port"      : port
        }
    config = RSYSLOG_TEMPLATE % values
    return config

def pid_location(port):
    # find the target location
    name = getpass.getuser()
    values = {
        "username" : name,
        "port" : port
        }
    location = PID_LOCATION % values
    # now make sure the directory exists
    directory = os.path.dirname(location)
    if not os.path.exists(directory):
        os.mkdir(directory)
    return location

if __name__ == "__main__":
    try:
        (options, args) = get_opts()
    except OptParserError as exc:
        exc.parser.error(str(exc))
        sys.exit(1)
    directory = os.path.join(os.getcwd(), options.log_root)
    config = generate_rsyslog_config(options.port, directory)
    if options.output:
        with open(options.output, 'w') as file:
            file.write(config)
        if options.stdout:
            pid = pid_location(options.port)
            print HINT % {
                "conf" : options.output,
                "pid" : pid
                }
    else:
        print config