Coverage for src/lib/python/isc/config/cfgmgr: 90%

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# Permission to use, copy, modify, and distribute this software for any

# purpose with or without fee is hereby granted, provided that the above

# copyright notice and this permission notice appear in all copies.

# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM

# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL

# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL

# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,

# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING

# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,

# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION

# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

"""This is the BIND 10 configuration manager, run by b10-cfgmgr.

It stores the system configuration, and sends updates of the

configuration to the modules that need them.

"""

import isc

import signal

import ast

import os

import copy

import tempfile

import json

import errno

from isc.cc import data

from isc.config import ccsession, config_data, module_spec

from isc.util.file import path_search

import bind10_config

import isc.log

from isc.log_messages.cfgmgr_messages import *

logger = isc.log.Logger("cfgmgr")

class ConfigManagerDataReadError(Exception):

"""This exception is thrown when there is an error while reading

the current configuration on startup."""

pass

class ConfigManagerDataEmpty(Exception):

"""This exception is thrown when the currently stored configuration

is not found, or appears empty."""

pass

class ConfigManagerData:

"""This class hold the actual configuration information, and

reads it from and writes it to persistent storage"""

def __init__(self, data_path, file_name):

"""Initialize the data for the configuration manager, and

set the version and path for the data store. Initializing

this does not yet read the database, a call to

read_from_file is needed for that.

In case the file_name is absolute, data_path is ignored

and the directory where the file_name lives is used instead.

"""

self.data = {}

self.data['version'] = config_data.BIND10_CONFIG_DATA_VERSION

if os.path.isabs(file_name):

self.db_filename = file_name

self.data_path = os.path.dirname(file_name)

else:

self.db_filename = data_path + os.sep + file_name

self.data_path = data_path

def read_from_file(data_path, file_name):

"""Read the current configuration found in the file file_name.

If file_name is absolute, data_path is ignored. Otherwise

we look for the file_name in data_path directory.

If the file does not exist, a ConfigManagerDataEmpty exception is

raised. If there is a parse error, or if the data in the file has

the wrong version, a ConfigManagerDataReadError is raised. In the

first case, it is probably safe to log and ignore. In the case of

the second exception, the best way is probably to report the error

and stop loading the system.

"""

config = ConfigManagerData(data_path, file_name)

file = None

try:

file = open(config.db_filename, 'r')

file_config = json.loads(file.read())

# handle different versions here

# If possible, we automatically convert to the new

# scheme and update the configuration

# If not, we raise an exception

106 if 'version' in file_config:

if file_config['version'] == config_data.BIND10_CONFIG_DATA_VERSION:

config.data = file_config

97 elif file_config['version'] == 1:

# only format change, no other changes necessary

file_config['version'] = 2

logger.info(CFGMGR_AUTOMATIC_CONFIG_DATABASE_UPDATE, 1, 2)

config.data = file_config

else:

104 if config_data.BIND10_CONFIG_DATA_VERSION > file_config['version']:

raise ConfigManagerDataReadError("Cannot load configuration file: version %d no longer supported" % file_config['version'])

else:

raise ConfigManagerDataReadError("Cannot load configuration file: version %d not yet supported" % file_config['version'])

else:

raise ConfigManagerDataReadError("No version information in configuration file " + config.db_filename)

except IOError as ioe:

# if IOError is 'no such file or directory', then continue

# (raise empty), otherwise fail (raise error)

113 if ioe.errno == errno.ENOENT:

raise ConfigManagerDataEmpty("No configuration file found")

else:

raise ConfigManagerDataReadError("Can't read configuration file: " + str(ioe))

except ValueError:

raise ConfigManagerDataReadError("Configuration file out of date or corrupt, please update or remove " + config.db_filename)

finally:

119 if file:

file.close();

return config

def write_to_file(self, output_file_name = None):

"""Writes the current configuration data to a file. If

output_file_name is not specified, the file used in

read_from_file is used."""

filename = None

try:

file = tempfile.NamedTemporaryFile(mode='w',

prefix="b10-config.db.",

dir=self.data_path,

delete=False)

filename = file.name

file.write(json.dumps(self.data))

file.write("\n")

file.close()

if output_file_name:

os.rename(filename, output_file_name)

else:

os.rename(filename, self.db_filename)

except IOError as ioe:

logger.error(CFGMGR_IOERROR_WHILE_WRITING_CONFIGURATION, ioe)

except OSError as ose:

logger.error(CFGMGR_OSERROR_WHILE_WRITING_CONFIGURATION, ose)

try:

146 if filename and os.path.exists(filename):

os.remove(filename)

except OSError:

# Ok if we really can't delete it anymore, leave it

pass

def rename_config_file(self, old_file_name=None, new_file_name=None):

"""Renames the given configuration file to the given new file name,

if it exists. If it does not exist, nothing happens.

If old_file_name is None (default), the file used in

read_from_file is used. If new_file_name is None (default), the

file old_file_name appended with .bak is used. If that file exists

already, .1 is appended. If that file exists, .2 is appended, etc.

"""

160 if old_file_name is None:

old_file_name = self.db_filename

if new_file_name is None:

new_file_name = old_file_name + ".bak"

if os.path.exists(new_file_name):

i = 1

while os.path.exists(new_file_name + "." + str(i)):

i += 1

new_file_name = new_file_name + "." + str(i)

if os.path.exists(old_file_name):

logger.info(CFGMGR_RENAMED_CONFIG_FILE, old_file_name, new_file_name)

os.rename(old_file_name, new_file_name)

def __eq__(self, other):

"""Returns True if the data contained is equal. data_path and

db_filename may be different."""

if type(other) != type(self):

return False

return self.data == other.data

class ConfigManager:

"""Creates a configuration manager. The data_path is the path

to the directory containing the configuraton file,

database_filename points to the configuration file.

If session is set, this will be used as the communication

channel session. If not, a new session will be created.

The ability to specify a custom session is for testing purposes

and should not be needed for normal usage."""

def __init__(self, data_path, database_filename, session=None,

clear_config=False):

"""Initialize the configuration manager. The data_path string

is the path to the directory where the configuration is

stored (in <data_path>/<database_filename> or in

<database_filename>, if it is absolute). The database_filename

is the config file to load. Session is an optional

cc-channel session. If this is not given, a new one is

created. If clear_config is True, the configuration file is

renamed and a new one is created."""

self.data_path = data_path

self.database_filename = database_filename

self.module_specs = {}

# Virtual modules are the ones which have no process running. The

# checking of validity is done by functions presented here instead

# of some other process

self.virtual_modules = {}

self.config = ConfigManagerData(data_path, database_filename)

206 if clear_config:

self.config.rename_config_file()

if session:

self.cc = session

else:

self.cc = isc.cc.Session()

self.cc.group_subscribe("ConfigManager")

self.cc.group_subscribe("Boss", "ConfigManager")

self.running = False

# As a core module, CfgMgr is different than other modules,

# as it does not use a ModuleCCSession, and hence needs

# to handle logging config on its own

self.log_config_data = config_data.ConfigData(

isc.config.module_spec_from_file(

path_search('logging.spec',

bind10_config.PLUGIN_PATHS)))

# store the logging 'module' name for easier reference

self.log_module_name = self.log_config_data.get_module_spec().get_module_name()

def check_logging_config(self, config):

226 if self.log_module_name in config:

ccsession.default_logconfig_handler(config[self.log_module_name],

self.log_config_data)

def notify_boss(self):

"""Notifies the Boss module that the Config Manager is running"""

self.cc.group_sendmsg({"running": "ConfigManager"}, "Boss")

def set_module_spec(self, spec):

"""Adds a ModuleSpec"""

self.module_specs[spec.get_module_name()] = spec

def set_virtual_module(self, spec, check_func):

"""Adds a virtual module with its spec and checking function."""

self.module_specs[spec.get_module_name()] = spec

self.virtual_modules[spec.get_module_name()] = check_func

def remove_module_spec(self, module_name):

"""Removes the full ModuleSpec for the given module_name.

Also removes the virtual module check function if it

was present.

Does nothing if the module was not present."""

249 if module_name in self.module_specs:

del self.module_specs[module_name]

if module_name in self.virtual_modules:

del self.virtual_modules[module_name]

def get_module_spec(self, module_name = None):

"""Returns the full ModuleSpec for the module with the given

module_name. If no module name is given, a dict will

be returned with 'name': module_spec values. If the

module name is given, but does not exist, an empty dict

is returned"""

if module_name:

if module_name in self.module_specs:

return self.module_specs[module_name].get_full_spec()

else:

# TODO: log error?

return {}

else:

result = {}

for module in self.module_specs:

result[module] = self.module_specs[module].get_full_spec()

return result

def get_config_spec(self, name = None):

"""Returns a dict containing 'module_name': config_spec for

all modules. If name is specified, only that module will

be included"""

config_data = {}

if name:

281 if name in self.module_specs:

config_data[name] = self.module_specs[name].get_config_spec()

else:

for module_name in self.module_specs.keys():

config_data[module_name] = self.module_specs[module_name].get_config_spec()

return config_data

def get_commands_spec(self, name = None):

"""Returns a dict containing 'module_name': commands_spec for

all modules. If name is specified, only that module will

be included"""

commands = {}

if name:

294 if name in self.module_specs:

commands[name] = self.module_specs[name].get_commands_spec()

else:

for module_name in self.module_specs.keys():

commands[module_name] = self.module_specs[module_name].get_commands_spec()

return commands

def get_statistics_spec(self, name = None):

"""Returns a dict containing 'module_name': statistics_spec for

all modules. If name is specified, only that module will

be included"""

statistics = {}

if name:

307 if name in self.module_specs:

statistics[name] = self.module_specs[name].get_statistics_spec()

else:

for module_name in self.module_specs.keys():

statistics[module_name] = self.module_specs[module_name].get_statistics_spec()

return statistics

def read_config(self):

"""Read the current configuration from the file specificied at init()"""

try:

self.config = ConfigManagerData.read_from_file(self.data_path,

self.\

database_filename)

self.check_logging_config(self.config.data);

except ConfigManagerDataEmpty:

# ok, just start with an empty config

self.config = ConfigManagerData(self.data_path,

self.database_filename)

def write_config(self):

"""Write the current configuration to the file specificied at init()"""

self.config.write_to_file()

def __handle_get_module_spec(self, cmd):

"""Private function that handles the 'get_module_spec' command"""

answer = {}

if cmd != None:

if type(cmd) == dict:

if 'module_name' in cmd and cmd['module_name'] != '':

module_name = cmd['module_name']

spec = self.get_module_spec(cmd['module_name'])

336 if type(spec) != type({}):

# this is a ModuleSpec object. Extract the

# internal spec.

spec = spec.get_full_spec()

answer = ccsession.create_answer(0, spec)

else:

answer = ccsession.create_answer(1, "Bad module_name in get_module_spec command")

else:

answer = ccsession.create_answer(1, "Bad get_module_spec command, argument not a dict")

else:

answer = ccsession.create_answer(0, self.get_module_spec())

return answer

def __handle_get_config_dict(self, cmd):

"""Private function that handles the 'get_config' command

where the command has been checked to be a dict"""

if 'module_name' in cmd and cmd['module_name'] != '':

module_name = cmd['module_name']

try:

return ccsession.create_answer(0, data.find(self.config.data, module_name))

except data.DataNotFoundError as dnfe:

# no data is ok, that means we have nothing that

# deviates from default values

return ccsession.create_answer(0, { 'version': config_data.BIND10_CONFIG_DATA_VERSION })

else:

return ccsession.create_answer(1, "Bad module_name in get_config command")

def __handle_get_config(self, cmd):

"""Private function that handles the 'get_config' command"""

if cmd != None:

if type(cmd) == dict:

return self.__handle_get_config_dict(cmd)

else:

return ccsession.create_answer(1, "Bad get_config command, argument not a dict")

else:

return ccsession.create_answer(0, self.config.data)

def __handle_set_config_module(self, module_name, cmd):

# the answer comes (or does not come) from the relevant module

# so we need a variable to see if we got it

answer = None

# todo: use api (and check the data against the definition?)

old_data = copy.deepcopy(self.config.data)

conf_part = data.find_no_exc(self.config.data, module_name)

update_cmd = None

use_part = None

if conf_part:

data.merge(conf_part, cmd)

use_part = conf_part

else:

conf_part = data.set(self.config.data, module_name, {})

data.merge(conf_part[module_name], cmd)

use_part = conf_part[module_name]

# The command to send

update_cmd = ccsession.create_command(ccsession.COMMAND_CONFIG_UPDATE,

use_part)

# TODO: This design might need some revisiting. We might want some

# polymorphism instead of branching. But it just might turn out it

# will get solved by itself when we move everything to virtual modules

# (which is possible solution to the offline configuration problem)

# or when we solve the incorect behaviour here when a config is

# rejected (spying modules don't know it was rejected and some modules

# might have been commited already).

if module_name in self.virtual_modules:

# The module is virtual, so call it to get the answer

try:

error = self.virtual_modules[module_name](use_part)

if error is None:

answer = ccsession.create_answer(0)

# OK, it is successful, send the notify, but don't wait

# for answer

seq = self.cc.group_sendmsg(update_cmd, module_name)

else:

answer = ccsession.create_answer(1, error)

# Make sure just a validating plugin don't kill the whole manager

except Exception as excp:

# Provide answer

answer = ccsession.create_answer(1, "Exception: " + str(excp))

else:

# Real module, send it over the wire to it

# send out changed info and wait for answer

seq = self.cc.group_sendmsg(update_cmd, module_name)

try:

# replace 'our' answer with that of the module

answer, env = self.cc.group_recvmsg(False, seq)

except isc.cc.SessionTimeout:

answer = ccsession.create_answer(1, "Timeout waiting for answer from " + module_name)

except isc.cc.SessionError as se:

logger.error(CFGMGR_BAD_UPDATE_RESPONSE_FROM_MODULE, module_name, se)

answer = ccsession.create_answer(1, "Unable to parse response from " + module_name + ": " + str(se))

if answer:

rcode, val = ccsession.parse_answer(answer)

if rcode == 0:

self.write_config()

else:

self.config.data = old_data

return answer

def __handle_set_config_all(self, cmd):

old_data = copy.deepcopy(self.config.data)

got_error = False

err_list = []

# The format of the command is a dict with module->newconfig

# sets, so we simply call set_config_module for each of those

for module in cmd:

if module != "version":

answer = self.__handle_set_config_module(module, cmd[module])

443 if answer == None:

got_error = True

err_list.append("No answer message from " + module)

else:

rcode, val = ccsession.parse_answer(answer)

448 if rcode != 0:

got_error = True

err_list.append(val)

457 if not got_error:

# if Logging config is in there, update our config as well

self.check_logging_config(cmd);

self.write_config()

return ccsession.create_answer(0)

else:

# TODO rollback changes that did get through, should we re-send update?

self.config.data = old_data

return ccsession.create_answer(1, " ".join(err_list))

def __handle_set_config(self, cmd):

"""Private function that handles the 'set_config' command"""

answer = None

if cmd == None:

return ccsession.create_answer(1, "Wrong number of arguments")

if len(cmd) == 2:

answer = self.__handle_set_config_module(cmd[0], cmd[1])

elif len(cmd) == 1:

answer = self.__handle_set_config_all(cmd[0])

else:

answer = ccsession.create_answer(1, "Wrong number of arguments")

if not answer:

answer = ccsession.create_answer(1, "No answer message from " + cmd[0])

return answer

def __handle_module_spec(self, spec):

"""Private function that handles the 'module_spec' command"""

# todo: validate? (no direct access to spec as

# todo: use ModuleSpec class

# todo: error checking (like keyerrors)

answer = {}

self.set_module_spec(spec)

self._send_module_spec_to_cmdctl(spec.get_module_name(),

spec.get_full_spec())

return ccsession.create_answer(0)

def __handle_module_stopping(self, arg):

"""Private function that handles a 'stopping' command;

The argument is of the form { 'module_name': <name> }.

If the module is known, it is removed from the known list,

and a message is sent to the Cmdctl channel to remove it as well.

If it is unknown, the message is ignored."""

if arg['module_name'] in self.module_specs:

del self.module_specs[arg['module_name']]

self._send_module_spec_to_cmdctl(arg['module_name'], None)

# This command is not expected to be answered

return None

def _send_module_spec_to_cmdctl(self, module_name, spec):

"""Sends the given module spec for the given module name to Cmdctl.

Parameters:

module_name: A string with the name of the module

spec: dict containing full module specification, as returned by

ModuleSpec.get_full_spec(). This argument may also be None,

in which case it signals Cmdctl to remove said module from

its list.

No response from Cmdctl is expected."""

spec_update = ccsession.create_command(ccsession.COMMAND_MODULE_SPECIFICATION_UPDATE,

[ module_name, spec ])

self.cc.group_sendmsg(spec_update, "Cmdctl")

def handle_msg(self, msg):

"""Handle a command from the cc channel to the configuration manager"""

answer = {}

cmd, arg = ccsession.parse_command(msg)

if cmd:

if cmd == ccsession.COMMAND_GET_COMMANDS_SPEC:

answer = ccsession.create_answer(0, self.get_commands_spec())

elif cmd == ccsession.COMMAND_GET_STATISTICS_SPEC:

answer = ccsession.create_answer(0, self.get_statistics_spec())

elif cmd == ccsession.COMMAND_GET_MODULE_SPEC:

answer = self.__handle_get_module_spec(arg)

elif cmd == ccsession.COMMAND_GET_CONFIG:

answer = self.__handle_get_config(arg)

elif cmd == ccsession.COMMAND_SET_CONFIG:

answer = self.__handle_set_config(arg)

elif cmd == ccsession.COMMAND_MODULE_STOPPING:

answer = self.__handle_module_stopping(arg)

elif cmd == ccsession.COMMAND_SHUTDOWN:

self.running = False

answer = ccsession.create_answer(0)

elif cmd == ccsession.COMMAND_MODULE_SPEC:

try:

answer = self.__handle_module_spec(isc.config.ModuleSpec(arg))

except isc.config.ModuleSpecError as dde:

answer = ccsession.create_answer(1, "Error in data definition: " + str(dde))

else:

answer = ccsession.create_answer(1, "Unknown command: " + str(cmd))

else:

answer = ccsession.create_answer(1, "Unknown message format: " + str(msg))

return answer

def run(self):

"""Runs the configuration manager."""

self.running = True

while (self.running):

# we just wait eternally for any command here, so disable

# timeouts for this specific recv

self.cc.set_timeout(0)

msg, env = self.cc.group_recvmsg(False)

# and set it back to whatever we default to

self.cc.set_timeout(isc.cc.Session.MSGQ_DEFAULT_TIMEOUT)

# ignore 'None' value (even though they should not occur)

# and messages that are answers to questions we did

# not ask

547 if msg is not None and not 'result' in msg:

answer = self.handle_msg(msg);

# Only respond if there actually is something to respond with

if answer is not None:

self.cc.group_reply(env, answer)

Coverage for src/lib/python/isc/config/cfgmgr : 90%

311 statements 283 run 28 missing 0 excluded 18 partial