# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""A simple JSON RPC client.
This client is compatible with any JSON RPC 2.0 implementation, including ours.
"""
import logging
from oslo_config import cfg
from oslo_utils import importutils
from oslo_utils import netutils
from oslo_utils import strutils
from oslo_utils import uuidutils
from ironic_lib.common.i18n import _
from ironic_lib import exception
from ironic_lib import json_rpc
from ironic_lib import keystone
CONF = cfg.CONF
LOG = logging.getLogger(__name__)
_SESSION = None
def _get_session():
global _SESSION
if _SESSION is None:
kwargs = {}
auth_strategy = json_rpc.auth_strategy()
if auth_strategy != 'keystone':
auth_type = 'none' if auth_strategy == 'noauth' else auth_strategy
CONF.set_default('auth_type', auth_type, group='json_rpc')
# Deprecated, remove in W
if auth_strategy == 'http_basic':
if CONF.json_rpc.http_basic_username:
kwargs['username'] = CONF.json_rpc.http_basic_username
if CONF.json_rpc.http_basic_password:
kwargs['password'] = CONF.json_rpc.http_basic_password
auth = keystone.get_auth('json_rpc', **kwargs)
session = keystone.get_session('json_rpc', auth=auth)
headers = {
'Content-Type': 'application/json'
}
# Adds options like connect_retries
_SESSION = keystone.get_adapter('json_rpc', session=session,
additional_headers=headers)
return _SESSION
[docs]
class Client(object):
"""JSON RPC client with ironic exception handling."""
allowed_exception_namespaces = [
"ironic_lib.exception.",
"ironic.common.exception.",
"ironic_inspector.utils.",
]
def __init__(self, serializer, version_cap=None):
self.serializer = serializer
self.version_cap = version_cap
[docs]
def can_send_version(self, version):
return _can_send_version(version, self.version_cap)
[docs]
def prepare(self, topic, version=None):
"""Prepare the client to transmit a request.
:param topic: Topic which is being addressed. Typically this
is the hostname of the remote json-rpc service.
:param version: The RPC API version to utilize.
"""
host = topic.split('.', 1)[1]
host, port = netutils.parse_host_port(host)
return _CallContext(
host, self.serializer, version=version,
version_cap=self.version_cap,
allowed_exception_namespaces=self.allowed_exception_namespaces,
port=port)
class _CallContext(object):
"""Wrapper object for compatibility with oslo.messaging API."""
def __init__(self, host, serializer, version=None, version_cap=None,
allowed_exception_namespaces=(), port=None):
if not port:
self.port = CONF.json_rpc.port
else:
self.port = int(port)
self.host = host
self.serializer = serializer
self.version = version
self.version_cap = version_cap
self.allowed_exception_namespaces = allowed_exception_namespaces
def _is_known_exception(self, class_name):
for ns in self.allowed_exception_namespaces:
if class_name.startswith(ns):
return True
return False
def _handle_error(self, error):
if not error:
return
message = error['message']
try:
cls = error['data']['class']
except KeyError:
LOG.error("Unexpected error from RPC: %s", error)
raise exception.IronicException(
_("Unexpected error raised by RPC"))
else:
if not self._is_known_exception(cls):
# NOTE(dtantsur): protect against arbitrary code execution
LOG.error("Unexpected error from RPC: %s", error)
raise exception.IronicException(
_("Unexpected error raised by RPC"))
raise importutils.import_object(cls, message,
code=error.get('code', 500))
def call(self, context, method, version=None, **kwargs):
"""Call conductor RPC.
Versioned objects are automatically serialized and deserialized.
:param context: Security context.
:param method: Method name.
:param version: RPC API version to use.
:param kwargs: Keyword arguments to pass.
:return: RPC result (if any).
"""
return self._request(context, method, cast=False, version=version,
**kwargs)
def cast(self, context, method, version=None, **kwargs):
"""Call conductor RPC asynchronously.
Versioned objects are automatically serialized and deserialized.
:param context: Security context.
:param method: Method name.
:param version: RPC API version to use.
:param kwargs: Keyword arguments to pass.
:return: None
"""
return self._request(context, method, cast=True, version=version,
**kwargs)
def _request(self, context, method, cast=False, version=None, **kwargs):
"""Call conductor RPC.
Versioned objects are automatically serialized and deserialized.
:param context: Security context.
:param method: Method name.
:param cast: If true, use a JSON RPC notification.
:param version: RPC API version to use.
:param kwargs: Keyword arguments to pass.
:return: RPC result (if any).
"""
params = {key: self.serializer.serialize_entity(context, value)
for key, value in kwargs.items()}
params['context'] = context.to_dict()
if version is None:
version = self.version
if version is not None:
_check_version(version, self.version_cap)
params['rpc.version'] = version
body = {
"jsonrpc": "2.0",
"method": method,
"params": params,
}
if not cast:
body['id'] = (getattr(context, 'request_id', None)
or uuidutils.generate_uuid())
scheme = 'http'
if CONF.json_rpc.use_ssl:
scheme = 'https'
url = '%s://%s:%d' % (scheme,
netutils.escape_ipv6(self.host),
self.port)
LOG.debug("RPC %s to %s with %s", method, url,
strutils.mask_dict_password(body))
try:
result = _get_session().post(url, json=body)
except Exception as exc:
LOG.debug('RPC %s to %s failed with %s', method, url, exc)
raise
LOG.debug('RPC %s to %s returned %s', method, url,
strutils.mask_password(result.text or '<None>'))
if not cast:
result = result.json()
self._handle_error(result.get('error'))
result = self.serializer.deserialize_entity(context,
result['result'])
return result
def _can_send_version(requested, version_cap):
if requested is None or version_cap is None:
return True
requested_parts = [int(item) for item in requested.split('.', 1)]
version_cap_parts = [int(item) for item in version_cap.split('.', 1)]
if requested_parts[0] != version_cap_parts[0]:
return False # major version mismatch
else:
return requested_parts[1] <= version_cap_parts[1]
def _check_version(requested, version_cap):
if not _can_send_version(requested, version_cap):
raise RuntimeError(_("Cannot send RPC request: requested version "
"%(requested)s, maximum allowed version is "
"%(version_cap)s") % {'requested': requested,
'version_cap': version_cap})
