# vim: set encoding=utf-8 et sw=4 sts=4 :
-from mako.template import Template
-from mako.runtime import Context
from os import path
-try:
- import cPickle as pickle
-except ImportError:
- import pickle
-__ALL__ = ('DhcpHandler',)
+from seqtools import Sequence
+from dispatcher import Handler, handler, HandlerError
+from services.util import Restorable, ConfigWriter
+from services.util import InitdHandler, TransactionalHandler
-pickle_ext = '.pkl'
-pickle_vars = 'vars'
-pickle_hosts = 'hosts'
+__ALL__ = ('DhcpHandler', 'Error', 'HostError', 'HostAlreadyExistsError',
+ 'HostNotFoundError', 'ParameterError', 'ParameterNotFoundError')
-config_filename = 'dhcpd.conf'
+class Error(HandlerError):
+ r"""
+ Error(message) -> Error instance :: Base DhcpHandler exception class.
-template_dir = path.join(path.dirname(__file__), 'templates')
+ All exceptions raised by the DhcpHandler inherits from this one, so you can
+ easily catch any DhcpHandler exception.
-class Host:
+ message - A descriptive error message.
+ """
+
+ def __init__(self, message):
+ r"Initialize the Error object. See class documentation for more info."
+ self.message = message
+
+ def __str__(self):
+ return self.message
+
+class HostError(Error, KeyError):
+ r"""
+ HostError(hostname) -> HostError instance
+
+ This is the base exception for all host related errors.
+ """
+
+ def __init__(self, hostname):
+ r"Initialize the object. See class documentation for more info."
+ self.message = 'Host error: "%s"' % hostname
+
+class HostAlreadyExistsError(HostError):
+ r"""
+ HostAlreadyExistsError(hostname) -> HostAlreadyExistsError instance
+
+ This exception is raised when trying to add a hostname that already exists.
+ """
+
+ def __init__(self, hostname):
+ r"Initialize the object. See class documentation for more info."
+ self.message = 'Host already exists: "%s"' % hostname
+
+class HostNotFoundError(HostError):
+ r"""
+ HostNotFoundError(hostname) -> HostNotFoundError instance
+
+ This exception is raised when trying to operate on a hostname that doesn't
+ exists.
+ """
+
+ def __init__(self, hostname):
+ r"Initialize the object. See class documentation for more info."
+ self.message = 'Host not found: "%s"' % hostname
+
+class ParameterError(Error, KeyError):
+ r"""
+ ParameterError(paramname) -> ParameterError instance
+
+ This is the base exception for all DhcpHandler parameters related errors.
+ """
+
+ def __init__(self, paramname):
+ r"Initialize the object. See class documentation for more info."
+ self.message = 'Parameter error: "%s"' % paramname
+
+class ParameterNotFoundError(ParameterError):
+ r"""
+ ParameterNotFoundError(hostname) -> ParameterNotFoundError instance
+
+ This exception is raised when trying to operate on a parameter that doesn't
+ exists.
+ """
+
+ def __init__(self, paramname):
+ r"Initialize the object. See class documentation for more info."
+ self.message = 'Parameter not found: "%s"' % paramname
+
+
+class Host(Sequence):
r"""Host(name, ip, mac) -> Host instance :: Class representing a host.
name - Host name, should be a fully qualified name, but no checks are done.
self.ip = ip
self.mac = mac
-class HostHandler:
+ def as_tuple(self):
+ r"Return a tuple representing the host."
+ return (self.name, self.ip, self.mac)
+
+class HostHandler(Handler):
r"""HostHandler(hosts) -> HostHandler instance :: Handle a list of hosts.
This class is a helper for DhcpHandler to do all the work related to hosts
r"Initialize HostHandler object, see class documentation for details."
self.hosts = hosts
+ @handler(u'Add a new host.')
def add(self, name, ip, mac):
r"add(name, ip, mac) -> None :: Add a host to the hosts list."
- # XXX deberia indexar por hostname o por ip? o por mac? :)
- # o por nada... Puedo tener un nombre con muchas IPs? Una IP con muchos
- # nombres? Una MAC con muchas IP? una MAC con muchos nombre? Etc...
+ if name in self.hosts:
+ raise HostAlreadyExistsError(name)
self.hosts[name] = Host(name, ip, mac)
+ @handler(u'Update a host.')
def update(self, name, ip=None, mac=None):
r"update(name[, ip[, mac]]) -> None :: Update a host of the hosts list."
if not name in self.hosts:
- raise KeyError('Host not found')
+ raise HostNotFoundError(name)
if ip is not None:
self.hosts[name].ip = ip
if mac is not None:
self.hosts[name].mac = mac
+ @handler(u'Delete a host.')
def delete(self, name):
r"delete(name) -> None :: Delete a host of the hosts list."
if not name in self.hosts:
- raise KeyError('Host not found')
+ raise HostNotFoundError(name)
del self.hosts[name]
- def list(self):
- r"""list() -> CSV string :: List all the hostnames.
+ @handler(u'Get information about a host.')
+ def get(self, name):
+ r"get(name) -> Host :: List all the information of a host."
+ if not name in self.hosts:
+ raise HostNotFoundError(name)
+ return self.hosts[name]
- The list is returned as a single CSV line with all the hostnames.
- """
- return ','.join(self.hosts)
+ @handler(u'List hosts.')
+ def list(self):
+ r"list() -> tuple :: List all the hostnames."
+ return self.hosts.keys()
+ @handler(u'Get information about all hosts.')
def show(self):
- r"""show() -> CSV string :: List all the complete hosts information.
-
- The hosts are returned as a CSV list with each host in a line, like:
- hostname,ip,mac
- """
- hosts = self.hosts.values()
- return '\n'.join('%s,%s,%s' % (h.name, h.ip, h.mac) for h in hosts)
+ r"show() -> list of Hosts :: List all the complete hosts information."
+ return self.hosts.values()
-class DhcpHandler:
+class DhcpHandler(Restorable, ConfigWriter, InitdHandler, TransactionalHandler):
r"""DhcpHandler([pickle_dir[, config_dir]]) -> DhcpHandler instance.
Handles DHCP service commands for the dhcpd program.
Both defaults to the current working directory.
"""
- def __init__(self, pickle_dir='.', config_dir='.'):
- r"Initialize DhcpHandler object, see class documentation for details."
- self.pickle_dir = pickle_dir
- self.config_dir = config_dir
- filename = path.join(template_dir, config_filename)
- self.template = Template(filename=filename)
- try:
- self._load()
- except IOError:
- # This is the first time the handler is used, create a basic
- # setup using some nice defaults
- self.hosts = dict()
- self.vars = dict(
+ _initd_name = 'dhcpd'
+
+ _persistent_vars = ('vars', 'hosts')
+
+ _restorable_defaults = dict(
+ hosts = dict(),
+ vars = dict(
domain_name = 'example.com',
dns_1 = 'ns1.example.com',
dns_2 = 'ns2.example.com',
net_start = '192.168.0.100',
net_end = '192.168.0.200',
net_gateway = '192.168.0.1',
- )
- self._dump()
- self._write_config()
+ ),
+ )
+
+ _config_writer_files = 'dhcpd.conf'
+ _config_writer_tpl_dir = path.join(path.dirname(__file__), 'templates')
+
+ def __init__(self, pickle_dir='.', config_dir='.'):
+ r"Initialize DhcpHandler object, see class documentation for details."
+ self._persistent_dir = pickle_dir
+ self._config_writer_cfg_dir = config_dir
+ self._config_build_templates()
+ self._restore()
self.host = HostHandler(self.hosts)
+ def _get_config_vars(self, config_file):
+ return dict(hosts=self.hosts.values(), **self.vars)
+
+ @handler(u'Set a DHCP parameter.')
def set(self, param, value):
r"set(param, value) -> None :: Set a DHCP parameter."
if not param in self.vars:
- raise KeyError('Parameter ' + param + ' not found')
+ raise ParameterNotFoundError(param)
self.vars[param] = value
- def list(self):
- r"""list() -> CSV string :: List all the parameter names.
+ @handler(u'Get a DHCP parameter.')
+ def get(self, param):
+ r"get(param) -> None :: Get a DHCP parameter."
+ if not param in self.vars:
+ raise ParameterNotFoundError(param)
+ return self.vars[param]
- The list is returned as a single CSV line with all the names.
- """
- return ','.join(self.vars)
+ @handler(u'List all available DHCP parameters.')
+ def list(self):
+ r"list() -> tuple :: List all the parameter names."
+ return self.vars.keys()
+ @handler(u'Get all DHCP parameters, with their values.')
def show(self):
- r"""show() -> CSV string :: List all the parameters (with their values).
-
- The parameters are returned as a CSV list with each parameter in a
- line, like:
- name,value
- """
- return '\n'.join(('%s,%s' % (k, v) for (k, v) in self.vars.items()))
-
- def start(self):
- r"start() -> None :: Start the DHCP service."
- #esto seria para poner en una interfaz
- #y seria el hook para arrancar el servicio
- pass
-
- def stop(self):
- r"stop() -> None :: Stop the DHCP service."
- #esto seria para poner en una interfaz
- #y seria el hook para arrancar el servicio
- pass
-
- def restart(self):
- r"restart() -> None :: Restart the DHCP service."
- #esto seria para poner en una interfaz
- #y seria el hook para arrancar el servicio
- pass
-
- def reload(self):
- r"reload() -> None :: Reload the configuration of the DHCP service."
- #esto seria para poner en una interfaz
- #y seria el hook para arrancar el servicio
- pass
-
- def commit(self):
- r"commit() -> None :: Commit the changes and reload the DHCP service."
- #esto seria para poner en una interfaz
- #y seria que hace el pickle deberia llamarse
- #al hacerse un commit
- self._dump()
- self._write_config()
- self.reload()
-
- def rollback(self):
- r"rollback() -> None :: Discard the changes not yet commited."
- self._load()
-
- def _dump(self):
- r"_dump() -> None :: Dump all persistent data to pickle files."
- # XXX podría ir en una clase base
- self._dump_var(self.vars, pickle_vars)
- self._dump_var(self.hosts, pickle_hosts)
-
- def _load(self):
- r"_load() -> None :: Load all persistent data from pickle files."
- # XXX podría ir en una clase base
- self.vars = self._load_var(pickle_vars)
- self.hosts = self._load_var(pickle_hosts)
-
- def _pickle_filename(self, name):
- r"_pickle_filename() -> string :: Construct a pickle filename."
- # XXX podría ir en una clase base
- return path.join(self.pickle_dir, name) + pickle_ext
-
- def _dump_var(self, var, name):
- r"_dump_var() -> None :: Dump a especific variable to a pickle file."
- # XXX podría ir en una clase base
- pickle.dump(var, file(self._pickle_filename(name), 'wb'), 2)
-
- def _load_var(self, name):
- r"_load_var() -> object :: Load a especific pickle file."
- # XXX podría ir en una clase base
- return pickle.load(file(self._pickle_filename(name)))
-
- def _write_config(self):
- r"_write_config() -> None :: Generate all the configuration files."
- # XXX podría ir en una clase base, ver como generalizar variables a
- # reemplazar en la template
- out_file = file(path.join(self.config_dir, config_filename), 'w')
- ctx = Context(out_file, hosts=self.hosts.values(), **self.vars)
- self.template.render_context(ctx)
+ r"show() -> (key, value) tuples :: List all the parameters."
+ return self.vars.items()
if __name__ == '__main__':
import os
- dhcp_handler = DhcpHandler()
+ h = DhcpHandler()
def dump():
print '-' * 80
- print 'Variables:', dhcp_handler.list()
- print dhcp_handler.show()
+ print 'Variables:', h.list()
+ print h.show()
print
- print 'Hosts:', dhcp_handler.host.list()
- print dhcp_handler.host.show()
+ print 'Hosts:', h.host.list()
+ print h.host.show()
print '-' * 80
dump()
- dhcp_handler.host.add('my_name','192.168.0.102','00:12:ff:56')
+ h.host.add('my_name','192.168.0.102','00:12:ff:56')
- dhcp_handler.host.update('my_name','192.168.0.192','00:12:ff:56')
+ h.host.update('my_name','192.168.0.192','00:12:ff:56')
- dhcp_handler.host.add('nico','192.168.0.188','00:00:00:00')
+ h.host.add('nico','192.168.0.188','00:00:00:00')
- dhcp_handler.set('domain_name','baryon.com.ar')
+ h.set('domain_name','baryon.com.ar')
try:
- dhcp_handler.set('sarasa','baryon.com.ar')
+ h.set('sarasa','baryon.com.ar')
except KeyError, e:
print 'Error:', e
- dhcp_handler.commit()
+ h.commit()
dump()
- for f in (pickle_vars + pickle_ext, pickle_hosts + pickle_ext,
- config_filename):
- os.unlink(f)
+ os.system('rm -f *.pkl ' + ' '.join(h._config_writer_files))