# Copyright 2014 Rackspace, Inc.
#
# 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.
from ironic_lib import metrics_utils
from oslo_log import log
from oslo_serialization import jsonutils
import requests
import retrying
from six.moves import http_client
from ironic.common import exception
from ironic.common.i18n import _
from ironic.conf import CONF
LOG = log.getLogger(__name__)
METRICS = metrics_utils.get_metrics_logger(__name__)
DEFAULT_IPA_PORTAL_PORT = 3260
[docs]class AgentClient(object):
"""Client for interacting with nodes via a REST API."""
@METRICS.timer('AgentClient.__init__')
def __init__(self):
self.session = requests.Session()
self.session.headers.update({'Content-Type': 'application/json'})
def _get_command_url(self, node):
"""Get URL endpoint for agent command request"""
agent_url = node.driver_internal_info.get('agent_url')
if not agent_url:
raise exception.IronicException(_('Agent driver requires '
'agent_url in '
'driver_internal_info'))
return ('%(agent_url)s/%(api_version)s/commands' %
{'agent_url': agent_url,
'api_version': CONF.agent.agent_api_version})
def _get_command_body(self, method, params):
"""Generate command body from method and params"""
return jsonutils.dumps({
'name': method,
'params': params,
})
@METRICS.timer('AgentClient._command')
@retrying.retry(
retry_on_exception=(
lambda e: isinstance(e, exception.AgentConnectionFailed)),
stop_max_attempt_number=CONF.agent.max_command_attempts)
def _command(self, node, method, params, wait=False,
command_timeout_factor=1):
"""Sends command to agent.
:param node: A Node object.
:param method: A string represents the command to be executed by
agent.
:param params: A dictionary containing params used to form the request
body.
:param wait: True to wait for the command to finish executing, False
otherwise.
:param command_timeout_factor: An integer, default 1, by which to
multiply the [agent]command_timeout
value. This is intended for use with
extremely long running commands to
the agent ramdisk where a general
timeout value should not be extended
in all cases.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command result from agent, see
get_commands_status for a sample.
"""
url = self._get_command_url(node)
body = self._get_command_body(method, params)
request_params = {
'wait': str(wait).lower()
}
LOG.debug('Executing agent command %(method)s for node %(node)s',
{'node': node.uuid, 'method': method})
try:
response = self.session.post(
url, params=request_params, data=body,
timeout=CONF.agent.command_timeout * command_timeout_factor)
except (requests.ConnectionError, requests.Timeout) as e:
msg = (_('Failed to connect to the agent running on node %(node)s '
'for invoking command %(method)s. Error: %(error)s') %
{'node': node.uuid, 'method': method, 'error': e})
LOG.error(msg)
raise exception.AgentConnectionFailed(reason=msg)
except requests.RequestException as e:
msg = (_('Error invoking agent command %(method)s for node '
'%(node)s. Error: %(error)s') %
{'method': method, 'node': node.uuid, 'error': e})
LOG.error(msg)
raise exception.IronicException(msg)
# TODO(russellhaering): real error handling
try:
result = response.json()
except ValueError:
msg = _(
'Unable to decode response as JSON.\n'
'Request URL: %(url)s\nRequest body: "%(body)s"\n'
'Response status code: %(code)s\n'
'Response: "%(response)s"'
) % ({'response': response.text, 'body': body, 'url': url,
'code': response.status_code})
LOG.error(msg)
raise exception.IronicException(msg)
LOG.debug('Agent command %(method)s for node %(node)s returned '
'result %(res)s, error %(error)s, HTTP status code %(code)d',
{'node': node.uuid, 'method': method,
'res': result.get('command_result'),
'error': result.get('command_error'),
'code': response.status_code})
if response.status_code >= http_client.BAD_REQUEST:
LOG.error('Agent command %(method)s for node %(node)s failed. '
'Expected 2xx HTTP status code, got %(code)d.',
{'method': method, 'node': node.uuid,
'code': response.status_code})
raise exception.AgentAPIError(node=node.uuid,
status=response.status_code,
error=result.get('faultstring'))
return result
[docs] @METRICS.timer('AgentClient.get_commands_status')
@retrying.retry(
retry_on_exception=(
lambda e: isinstance(e, exception.AgentConnectionFailed)),
stop_max_attempt_number=CONF.agent.max_command_attempts)
def get_commands_status(self, node):
"""Get command status from agent.
:param node: A Node object.
:return: A list of command results, each result is related to a
command been issued to agent. A typical result can be:
::
{
'command_name': <command name related to the result>,
'command_params': <params related with the command>,
'command_status': <current command status,
e.g. 'RUNNING', 'SUCCEEDED', 'FAILED'>,
'command_error': <error message if command execution
failed>,
'command_result': <command result if command execution
succeeded, the value is command specific,
e.g.:
* a dictionary containing keys clean_result
and clean_step for the command
clean.execute_clean_step;
* a string representing result message for
the command standby.cache_image;
* None for the command standby.sync.>
}
"""
url = self._get_command_url(node)
LOG.debug('Fetching status of agent commands for node %s', node.uuid)
try:
resp = self.session.get(url, timeout=CONF.agent.command_timeout)
except (requests.ConnectionError, requests.Timeout) as e:
msg = (_('Failed to connect to the agent running on node %(node)s '
'to collect commands status. '
'Error: %(error)s') %
{'node': node.uuid, 'error': e})
LOG.error(msg)
raise exception.AgentConnectionFailed(reason=msg)
result = resp.json()['commands']
status = '; '.join('%(cmd)s: result "%(res)s", error "%(err)s"' %
{'cmd': r.get('command_name'),
'res': r.get('command_result'),
'err': r.get('command_error')}
for r in result)
LOG.debug('Status of agent commands for node %(node)s: %(status)s',
{'node': node.uuid, 'status': status})
return result
[docs] @METRICS.timer('AgentClient.prepare_image')
def prepare_image(self, node, image_info, wait=False):
"""Call the `prepare_image` method on the node.
:param node: A Node object.
:param image_info: A dictionary containing various image related
information.
:param wait: True to wait for the command to finish executing, False
otherwise.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command status from agent.
See :func:`get_commands_status` for a command result sample.
"""
LOG.debug('Preparing image %(image)s on node %(node)s.',
{'image': image_info.get('id'),
'node': node.uuid})
params = {'image_info': image_info}
# this should be an http(s) URL
configdrive = node.instance_info.get('configdrive')
if configdrive is not None:
params['configdrive'] = configdrive
return self._command(node=node,
method='standby.prepare_image',
params=params,
wait=wait)
[docs] @METRICS.timer('AgentClient.start_iscsi_target')
def start_iscsi_target(self, node, iqn,
portal_port=DEFAULT_IPA_PORTAL_PORT,
wipe_disk_metadata=False):
"""Expose the node's disk as an ISCSI target.
:param node: an Ironic node object
:param iqn: iSCSI target IQN
:param portal_port: iSCSI portal port
:param wipe_disk_metadata: True if the agent should wipe first the
disk magic strings like the partition
table, RAID or filesystem signature.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
params = {'iqn': iqn,
'portal_port': portal_port,
'wipe_disk_metadata': wipe_disk_metadata}
return self._command(node=node,
method='iscsi.start_iscsi_target',
params=params,
wait=True)
[docs] @METRICS.timer('AgentClient.install_bootloader')
def install_bootloader(self, node, root_uuid, efi_system_part_uuid=None,
prep_boot_part_uuid=None):
"""Install a boot loader on the image.
:param node: A node object.
:param root_uuid: The UUID of the root partition.
:param efi_system_part_uuid: The UUID of the efi system partition
where the bootloader will be installed to, only used for uefi
boot mode.
:param prep_boot_part_uuid: The UUID of the PReP Boot partition where
the bootloader will be installed to when local booting a
partition image on a ppc64* system.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
params = {'root_uuid': root_uuid,
'efi_system_part_uuid': efi_system_part_uuid,
'prep_boot_part_uuid': prep_boot_part_uuid}
# NOTE(TheJulia): This command explicitly sends a larger timeout
# factor to the _command call such that the agent ramdisk has enough
# time to perform its work.
# TODO(TheJulia): We should likely split install_bootloader into many
# commands at some point, even though that would not be backwards
# compatible. We could at least begin to delineate the commands apart
# over the next cycle or two so we don't need a command timeout
# extension factor.
return self._command(node=node,
method='image.install_bootloader',
params=params,
wait=True,
command_timeout_factor=2)
[docs] @METRICS.timer('AgentClient.get_clean_steps')
def get_clean_steps(self, node, ports):
"""Get clean steps from agent.
:param node: A node object.
:param ports: Ports associated with the node.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
The value of key command_result is in the form of:
::
{
'clean_steps': <a list of clean steps>,
'hardware_manager_version': <manager version>
}
"""
params = {
'node': node.as_dict(secure=True),
'ports': [port.as_dict() for port in ports]
}
return self._command(node=node,
method='clean.get_clean_steps',
params=params,
wait=True)
[docs] @METRICS.timer('AgentClient.execute_clean_step')
def execute_clean_step(self, step, node, ports):
"""Execute specified clean step.
:param step: A clean step dictionary to execute.
:param node: A Node object.
:param ports: Ports associated with the node.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
The value of key command_result is in the form of:
::
{
'clean_result': <the result of execution, step specific>,
'clean_step': <the clean step issued to agent>
}
"""
params = {
'step': step,
'node': node.as_dict(secure=True),
'ports': [port.as_dict() for port in ports],
'clean_version': node.driver_internal_info.get(
'hardware_manager_version')
}
return self._command(node=node,
method='clean.execute_clean_step',
params=params)
[docs] @METRICS.timer('AgentClient.power_off')
def power_off(self, node):
"""Soft powers off the bare metal node by shutting down ramdisk OS.
:param node: A Node object.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
return self._command(node=node,
method='standby.power_off',
params={})
[docs] @METRICS.timer('AgentClient.sync')
def sync(self, node):
"""Flush file system buffers forcing changed blocks to disk.
:param node: A Node object.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
return self._command(node=node,
method='standby.sync',
params={},
wait=True)
[docs] @METRICS.timer('AgentClient.collect_system_logs')
def collect_system_logs(self, node):
"""Collect and package diagnostic and support data from the ramdisk.
:param node: A Node object.
:raises: IronicException when failed to issue the request or there was
a malformed response from the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
return self._command(node=node,
method='log.collect_system_logs',
params={},
wait=True)
[docs] @METRICS.timer('AgentClient.finalize_rescue')
def finalize_rescue(self, node):
"""Instruct the ramdisk to finalize entering of rescue mode.
:param node: A Node object.
:raises: IronicException if rescue_password is missing, or when failed
to issue the request, or there was a malformed response from
the agent.
:raises: AgentAPIError when agent failed to execute specified command.
:returns: A dict containing command response from agent.
See :func:`get_commands_status` for a command result sample.
"""
rescue_pass = node.instance_info.get('rescue_password')
if not rescue_pass:
raise exception.IronicException(_('Agent rescue requires '
'rescue_password in '
'instance_info'))
params = {'rescue_password': rescue_pass}
return self._command(node=node,
method='rescue.finalize_rescue',
params=params)
