# 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
+try:
+ from dispatcher import handler
+except ImportError:
+ def handler(f): return f # NOP for testing
+
+__ALL__ = ('DhcpHandler',)
+
+pickle_ext = '.pkl'
+pickle_vars = 'vars'
+pickle_hosts = 'hosts'
+
+config_filename = 'dhcpd.conf'
+
+template_dir = path.join(path.dirname(__file__), 'templates')
+
+class Error(RuntimeError):
+ r"""
+ Error(command) -> Error instance :: Base DhcpHandler exception class.
+
+ All exceptions raised by the DhcpHandler inherits from this one, so you can
+ easily catch any DhcpHandler exception.
+
+ 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
-from mako.template import Template
-from mako.runtime import Context
class Host:
+ 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.
+ ip - IP assigned to the hostname.
+ mac - MAC address to associate to the hostname.
+ """
+
def __init__(self, name, ip, mac):
+ r"Initialize Host object, see class documentation for details."
self.name = name
self.ip = ip
self.mac = mac
- def __repr__(self):
- return 'Host(name="%s", ip="%s", mac="%s")' % (
- self.name, self.ip, self.mac)
class HostHandler:
+ 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
+ administration.
+
+ hosts - A dictionary with string keys (hostnames) and Host instances values.
+ """
def __init__(self, hosts):
+ r"Initialize HostHandler object, see class documentation for details."
self.hosts = hosts
+ @handler
def add(self, name, ip, mac):
- #deberia indexar por hostname o por ip? o por mac? :)
- # Mejor por nada...
+ r"add(name, ip, mac) -> None :: Add a host to the hosts list."
+ if name in self.hosts:
+ raise HostAlreadyExistsError(name)
self.hosts[name] = Host(name, ip, mac)
+ @handler
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 HostNotFoundError(name)
if ip is not None:
self.hosts[name].ip = ip
if mac is not None:
self.hosts[name].mac = mac
+ @handler
def delete(self, name):
+ r"delete(name) -> None :: Delete a host of the hosts list."
+ if not name in self.hosts:
+ raise HostNotFoundError(name)
del self.hosts[name]
+ @handler
def list(self):
+ r"""list() -> CSV string :: List all the hostnames.
+
+ The list is returned as a single CSV line with all the hostnames.
+ """
return ','.join(self.hosts)
+ @handler
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)
class DhcpHandler:
- r"""class that handles DHCP service using dhcpd program"""
-
- def __init__(self):
- self.hosts = dict()
- self.vars = dict(
- domain_name = 'my_domain_name',
- dns_1 = 'my_ns1',
- dns_2 = 'my_ns2',
- net_address = '192.168.0.0',
- net_mask = '255.255.255.0',
- net_start = '192.168.0.100',
- net_end = '192.168.0.200',
- net_gateway = '192.168.0.1',
- )
+ r"""DhcpHandler([pickle_dir[, config_dir]]) -> DhcpHandler instance.
+
+ Handles DHCP service commands for the dhcpd program.
+
+ pickle_dir - Directory where to write the persistent configuration data.
+
+ config_dir - Directory where to store de generated configuration files.
+
+ 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(
+ domain_name = 'example.com',
+ dns_1 = 'ns1.example.com',
+ dns_2 = 'ns2.example.com',
+ net_address = '192.168.0.0',
+ net_mask = '255.255.255.0',
+ net_start = '192.168.0.100',
+ net_end = '192.168.0.200',
+ net_gateway = '192.168.0.1',
+ )
+ self._dump()
+ self._write_config()
self.host = HostHandler(self.hosts)
+ @handler
def set(self, param, value):
- if param in self.vars:
- self.vars[param] = value
- else:
- raise KeyError("Parameter " + param + " not found")
+ r"set(param, value) -> None :: Set a DHCP parameter."
+ if not param in self.vars:
+ raise ParameterNotFoundError(param)
+ self.vars[param] = value
+ @handler
def list(self):
+ r"""list() -> CSV string :: List all the parameter names.
+
+ The list is returned as a single CSV line with all the names.
+ """
return ','.join(self.vars)
+ @handler
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()))
+ @handler
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
+ @handler
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
+
+ @handler
+ 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
+ @handler
+ 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
+
+ @handler
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
- pickle.dump(self.vars, file('pickled/vars.pkl', 'wb'), 2)
- pickle.dump(self.hosts, file('pickled/hosts.pkl', 'wb'), 2)
- tpl = Template(filename='templates/dhcpd.conf')
- ctx = Context(file('generated/dhcpd.conf', 'w'),
- hosts=self.hosts.values(), **self.vars)
- tpl.render_context(ctx)
+ self._dump()
+ self._write_config()
+ self.reload()
+
+ @handler
+ 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
+ pkl_file = file(self._pickle_filename(name), 'wb')
+ pickle.dump(var, pkl_file, 2)
+ pkl_file.close()
+
+ 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)
+ out_file.close()
if __name__ == '__main__':
- config = DhcpHandler()
+ import os
+
+ dhcp_handler = DhcpHandler()
- config.host.add('my_name','192.168.0.102','00:12:ff:56')
+ def dump():
+ print '-' * 80
+ print 'Variables:', dhcp_handler.list()
+ print dhcp_handler.show()
+ print
+ print 'Hosts:', dhcp_handler.host.list()
+ print dhcp_handler.host.show()
+ print '-' * 80
- config.host.update('my_name','192.168.0.192','00:12:ff:56')
+ dump()
- config.host.add('nico','192.168.0.188','00:00:00:00')
+ dhcp_handler.host.add('my_name','192.168.0.102','00:12:ff:56')
- config.set('domain_name','baryon.com.ar')
+ dhcp_handler.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')
+
+ dhcp_handler.set('domain_name','baryon.com.ar')
try:
- config.set('sarasa','baryon.com.ar')
+ dhcp_handler.set('sarasa','baryon.com.ar')
except KeyError, e:
print 'Error:', e
- config.commit()
-
- print 'Variables:', config.list()
- print config.show()
+ dhcp_handler.commit()
- print 'Hosts:', config.host.list()
- print config.host.show()
+ dump()
- vars = pickle.load(file('pickled/vars.pkl'))
- hosts = pickle.load(file('pickled/hosts.pkl'))
- print 'Pickled vars:', vars
- print 'Pickled hosts:', hosts
+ for f in (pickle_vars + pickle_ext, pickle_hosts + pickle_ext,
+ config_filename):
+ os.unlink(f)
projects / software / pymin.git / blobdiff