1 # Copyright 2015 Intel Corporation.
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
15 """Wrapper for an OVS bridge for convenient use of ``ovs-vsctl`` and
18 Much of this code is based on ``ovs-lib.py`` from Open Stack:
20 https://github.com/openstack/neutron/blob/6eac1dc99124ca024d6a69b3abfa3bc69c735667/neutron/agent/linux/ovs_lib.py
27 from tools import tasks
28 from conf import settings
30 _OVS_VSCTL_BIN = os.path.join(settings.getValue('OVS_DIR'), 'utilities',
32 _OVS_OFCTL_BIN = os.path.join(settings.getValue('OVS_DIR'), 'utilities',
35 _OVS_BRIDGE_NAME = settings.getValue('VSWITCH_BRIDGE_NAME')
37 _CACHE_FILE_NAME = '/tmp/vsperf_flows_cache'
40 """Add/remove/show datapaths using ``ovs-ofctl``.
42 def __init__(self, timeout=10):
45 :param timeout: Timeout to be used for each command
49 self.logger = logging.getLogger(__name__)
50 self.timeout = timeout
54 def run_vsctl(self, args, check_error=False):
55 """Run ``ovs-vsctl`` with supplied arguments.
57 :param args: Arguments to pass to ``ovs-vsctl``
58 :param check_error: Throw exception on error
62 cmd = ['sudo', _OVS_VSCTL_BIN, '--timeout', str(self.timeout)] + args
63 return tasks.run_task(
64 cmd, self.logger, 'Running ovs-vsctl...', check_error)
68 def add_br(self, br_name=_OVS_BRIDGE_NAME, params=None):
71 :param br_name: Name of bridge
73 :return: Instance of :class OFBridge:
78 self.logger.debug('add bridge')
79 self.run_vsctl(['add-br', br_name]+params)
81 return OFBridge(br_name, self.timeout)
83 def del_br(self, br_name=_OVS_BRIDGE_NAME):
86 :param br_name: Name of bridge
90 self.logger.debug('delete bridge')
91 self.run_vsctl(['del-br', br_name])
94 class OFBridge(OFBase):
95 """Control a bridge instance using ``ovs-vsctl`` and ``ovs-ofctl``.
97 def __init__(self, br_name=_OVS_BRIDGE_NAME, timeout=10):
100 :param br_name: Bridge name
101 :param timeout: Timeout to be used for each command
105 super(OFBridge, self).__init__(timeout)
106 self.br_name = br_name
108 self._cache_file = None
119 def __exit__(self, type_, value, traceback):
127 def run_ofctl(self, args, check_error=False, timeout=None):
128 """Run ``ovs-ofctl`` with supplied arguments.
130 :param args: Arguments to pass to ``ovs-ofctl``
131 :param check_error: Throw exception on error
135 tmp_timeout = self.timeout if timeout == None else timeout
136 cmd = ['sudo', _OVS_OFCTL_BIN, '-O', 'OpenFlow13', '--timeout',
137 str(tmp_timeout)] + args
138 return tasks.run_task(
139 cmd, self.logger, 'Running ovs-ofctl...', check_error)
141 def create(self, params=None):
147 self.logger.debug('create bridge')
148 self.add_br(self.br_name, params=params)
153 self.logger.debug('destroy bridge')
154 self.del_br(self.br_name)
159 self.logger.debug('reset bridge')
165 def add_port(self, port_name, params):
166 """Add port to bridge.
168 :param port_name: Name of port
169 :param params: Additional list of parameters to add-port
171 :return: OpenFlow port number for the port
173 self.logger.debug('add port')
174 self.run_vsctl(['add-port', self.br_name, port_name]+params)
176 # This is how port number allocation works currently
177 # This possibly will not work correctly if there are port deletions
179 of_port = len(self._ports) + 1
180 self._ports[port_name] = (of_port, params)
183 def del_port(self, port_name):
184 """Remove port from bridge.
186 :param port_name: Name of port
190 self.logger.debug('delete port')
191 self.run_vsctl(['del-port', self.br_name, port_name])
192 self._ports.pop(port_name)
194 def set_db_attribute(self, table_name, record, column, value):
195 """Set database attribute.
197 :param table_name: Name of table
198 :param record: Name of record
199 :param column: Name of column
200 :param value: Value to set
204 self.logger.debug('set attribute')
205 self.run_vsctl(['set', table_name, record, '%s=%s' % (column, value)])
208 """Get the ports of this bridge
210 Structure of the returned ports dictionary is
211 'portname': (openflow_port_number, extra_parameters)
216 (1, ['--', 'set', 'Interface', 'dpdkport0', 'type=dpdk']),
218 (2, ['--', 'set', 'Interface', 'dpdkvhostport0',
222 :return: Dictionary of ports
226 def clear_db_attribute(self, table_name, record, column):
227 """Clear database attribute.
229 :param table_name: Name of table
230 :param record: Name of record
231 :param column: Name of column
235 self.logger.debug('clear attribute')
236 self.run_vsctl(['clear', table_name, record, column])
240 def add_flow(self, flow, cache='off'):
241 """Add flow to bridge.
243 :param flow: Flow description as a dictionary
244 For flow dictionary structure, see function flow_key
248 # insert flows from cache into OVS if needed
250 if self._cache_file == None:
251 self.logger.error('flow cache flush called, but nothing is cached')
253 self.logger.debug('flows cached in %s will be added to the bridge', _CACHE_FILE_NAME)
254 self._cache_file.close()
255 self._cache_file = None
256 self.run_ofctl(['add-flows', self.br_name, _CACHE_FILE_NAME], timeout=600)
259 if not flow.get('actions'):
260 self.logger.error('add flow requires actions')
263 _flow_key = flow_key(flow)
264 self.logger.debug('key : %s', _flow_key)
266 # insert flow to the cache or OVS
268 # create and open cache file if needed
269 if self._cache_file == None:
270 self._cache_file = open(_CACHE_FILE_NAME, 'w')
271 self._cache_file.write(_flow_key + '\n')
273 self.run_ofctl(['add-flow', self.br_name, _flow_key])
275 def del_flow(self, flow):
276 """Delete flow from bridge.
278 :param flow: Flow description as a dictionary
279 For flow dictionary structure, see function flow_key
280 flow=None will delete all flows
284 self.logger.debug('delete flow')
285 _flow_key = flow_key(flow)
286 self.logger.debug('key : %s', _flow_key)
287 self.run_ofctl(['del-flows', self.br_name, _flow_key])
290 """Delete all flows from bridge.
292 self.logger.debug('delete flows')
293 self.run_ofctl(['del-flows', self.br_name])
295 def dump_flows(self):
296 """Dump all flows from bridge.
298 self.logger.debug('dump flows')
299 self.run_ofctl(['dump-flows', self.br_name], timeout=120)
306 """Model a flow key string for ``ovs-ofctl``.
308 Syntax taken from ``ovs-ofctl`` manpages:
309 http://openvswitch.org/cgi-bin/ovsman.cgi?page=utilities%2Fovs-ofctl.8
311 Example flow dictionary:
315 'actions': ['output:3']
318 :param flow: Flow description as a dictionary
323 _flow_add_key = string.Template('${fields},action=${actions}')
324 _flow_del_key = string.Template('${fields}')
328 user_params = (x for x in list(flow.items()) if x[0] != 'actions')
329 for (key, default) in user_params:
330 field_params.append('%(field)s=%(value)s' %
331 {'field': key, 'value': default})
333 field_params = ','.join(field_params)
336 'fields': field_params,
339 # no actions == delete key
340 if 'actions' in flow:
341 _flow_key_param['actions'] = ','.join(flow['actions'])
343 flow_str = _flow_add_key.substitute(_flow_key_param)
345 flow_str = _flow_del_key.substitute(_flow_key_param)