Source code for ironic_lib.json_rpc.client

# 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})