zenglobalconf

#!/usr/bin/env python
##############################################################################
# 
# Copyright (C) Zenoss, Inc. 2010, all rights reserved.
# 
# This content is made available according to terms specified in
# License.zenoss under the directory where your Zenoss product is installed.
# 
##############################################################################


import optparse
import os
import re
import sys
import tempfile


# Handles updating or removing settings from $ZENHOME/etc/global.conf. All
# updates are performed atomically using a temporary file to prevent losing
# configuration.

CONF_FILE = ''

SETTINGS_DELIM = re.compile(r'\s+')

def zenPath(*args):
    return os.path.abspath(os.path.join(os.environ['ZENHOME'], *args))

def parse_settings(conf_file):
    if not os.path.isfile(conf_file):
        return
    with open(conf_file) as global_conf:
        for line in global_conf:
            name = None
            value = None
            if line and not line.lstrip().startswith('#'):
                fields = re.split(SETTINGS_DELIM, line.rstrip(), 1)
                if len(fields) == 1:
                    name, value = fields[0],None
                elif len(fields) > 1:
                    name, value = fields
            yield (line, name, value)

def create_tmpfile(path):
    statinfo = os.stat(path)
    (tmpfd,tmpname) = tempfile.mkstemp(suffix='.conf',dir=os.path.dirname(path),text=True)
    # Clone permissions from original file
    os.chmod(tmpname, statinfo.st_mode)
    os.chown(tmpname, statinfo.st_uid, statinfo.st_gid)
    return tmpfd, tmpname

def print_setting(setting_name):
    filename = CONF_FILE
    for line, name, value in parse_settings(filename):
        if name == setting_name :
            if value is not None:
                print value
            break
    else:
        sys.exit(-1)

def remove_settings(settings_to_remove):
    filename = CONF_FILE
    (tmpfd,tmpname) = create_tmpfile(filename)
    output_file = os.fdopen(tmpfd, 'wb')
    found_settings = set()
    try:
        for line, name, value in parse_settings(filename):
            if name is None or name not in settings_to_remove:
                output_file.write(line)
            else:
                found_settings.add(name)
        output_file.close()
        if len(found_settings) > 0:
            os.rename(tmpname, filename)
    finally:
        try:
            os.remove(tmpname)
        except OSError:
            pass

def update_settings(settings_dict):
    filename = CONF_FILE
    (tmpfd,tmpname) = create_tmpfile(filename)
    output_file = os.fdopen(tmpfd, 'wb')
    found_settings = set()
    try:
        for line, name, value in parse_settings(filename):
            if name is None or not name in settings_dict:
                output_file.write(line)
            elif name not in found_settings:
                newval = settings_dict.get(name)
                output_file.write("%s %s\n" % (name, newval))
                found_settings.add(name)

        for name, val in settings_dict.iteritems():
            if not name in found_settings:
                output_file.write("%s %s\n" % (name, val))

        output_file.close()
        os.rename(tmpname, filename)
    finally:
        try:
            os.remove(tmpname)
        except OSError:
            pass

def main():
    if 'ZENHOME' not in os.environ:
        print >> sys.stderr, (
            "ZENHOME not set. You must run this script as the zenoss user.")
        sys.exit(1)

    parser = optparse.OptionParser(usage='%prog <-p|-r|-u> prop_name[=prop_val] [...]')
    parser.add_option('-p', '--print', dest='get', action="store_true", default=False,
                      help='Prints setting from the configuration file.')
    parser.add_option('-r', '--remove', dest='remove', action="store_true", default=False,
                      help='Removes settings from the configuration file.')
    parser.add_option('-u', '--update', dest='update', action="store_true", default=False,
                      help='Adds or updates settings in the configuration file.')
    parser.add_option('-s', '--sync-zope-conf', dest='synczope', action="store_true", default=False,
                      help='Syncs the ZODB db conf from global from to zodb_db_main.conf.')
    parser.add_option('-f', '--conffile', dest='conffile', default=zenPath('etc','global.conf'),
                      help='Zenoss conf file')
    
    (options, args) = parser.parse_args(args=sys.argv[1:])

    global CONF_FILE
    CONF_FILE = options.conffile

    numcmds = int(options.get) + int(options.remove) + int(options.update) + int(options.synczope)
    if not numcmds:
        parser.error("Must specify command (-p|-r|-u|-s)")
    if numcmds > 1:
        parser.error("Only one command can be specified (-p|-r|-u|-s)")

    if len(args) == 0 and not options.synczope:
        parser.error("required property names not provided")

    if options.synczope:
        if CONF_FILE != zenPath('etc', 'global.conf'):
            print "--sync-zope-conf only valid with global.conf"
            sys.exit(1)
        # load zcml for the product
        from Products.ZenUtils.zenpackload import load_zenpacks
        from Products.Five import zcml
        load_zenpacks()
        zcml.load_site()
        # look up the utility
        from zope.component import getUtility
        from Products.ZenUtils.ZodbFactory import IZodbFactoryLookup
        connectionFactory = getUtility(IZodbFactoryLookup).get()
        zodbConf = connectionFactory.getZopeZodbConf()
        zodbSessionConf = connectionFactory.getZopeZodbSessionConf()

        def write_zodb_conf(confname, contents):
            dirname = zenPath('etc')
            tconf = None
            try:
                tconf = tempfile.NamedTemporaryFile(prefix=confname,
                                                    dir=dirname,
                                                    delete=False)
                os.chmod(tconf.name, 0600)
                tconf.write(contents)
                tconf.close()
                os.rename(tconf.name, zenPath('etc', confname))
            finally:
                if tconf is not None and os.path.exists(tconf.name):
                    os.unlink(tconf.name)
        
        write_zodb_conf('zodb_db_main.conf', zodbConf)
        write_zodb_conf('zodb_db_session.conf', zodbSessionConf)
        sys.exit(0)
    elif options.get:
        if len(args) > 1:
            parser.error("Print option only takes one setting name")
        print_setting(args[0])
    elif options.remove:
        remove_settings(args)
    else:
        argsdict = {}
        for arg in args:
            splitargs = arg.split('=', 1) + ['',]
            name = splitargs[0].strip()
            value = splitargs[1].strip()
            if len(name) == 0:
                parser.error("invalid argument: %s" % arg)
            argsdict[name] = value
        update_settings(argsdict)

if __name__ == '__main__':
    main()