build.main.Main._send_flow_mods_from_request() - Code Metrics - Inspection of "Add support for non-strict exclusion in the consis..." - kytos/flow_manager - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#117)

by Carlos

created 2021-04-28 14:37 UTC

build.main.Main._send_flow_mods_from_request() B

↳ Parent: build.main

Complexity

Conditions

Size

Total Lines	23
Code Lines	17

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	16
CRAP Score	7

Importance

Changes

Metric	Value
cc	7
eloc	17
nop	4
dl	0
loc	23
ccs	16
cts	16
cp	1
crap	7
rs	8
c	0
b	0
f	0

"""kytos/flow_manager NApp installs, lists and deletes switch flows."""
from collections import OrderedDict
from copy import deepcopy

from flask import jsonify, request
from pyof.v0x01.asynchronous.error_msg import BadActionCode
from pyof.v0x01.common.phy_port import PortConfig

from kytos.core import KytosEvent, KytosNApp, log, rest
from kytos.core.helpers import listen_to
from napps.kytos.flow_manager.match import match_flow
from napps.kytos.flow_manager.storehouse import StoreHouse
from napps.kytos.of_core.flow import FlowFactory

from .exceptions import InvalidCommandError
from .settings import CONSISTENCY_INTERVAL, FLOWS_DICT_MAX_SIZE


class Main(KytosNApp):
    """Main class to be used by Kytos controller."""

    def setup(self):
        """Replace the 'init' method for the KytosApp subclass.

        The setup method is automatically called by the run method.
        Users shouldn't call this method directly.
        """
        log.debug("flow-manager starting")
        self._flow_mods_sent = OrderedDict()
        self._flow_mods_sent_max_size = FLOWS_DICT_MAX_SIZE

        # Storehouse client to save and restore flow data:
        self.storehouse = StoreHouse(self.controller)

        # Format of stored flow data:
        # {'flow_persistence': {'dpid_str': {'flow_list': [
        #                                     {'command': '<add|delete>',
        #                                      'flow': {flow_dict}}]}}}
        self.stored_flows = {}
        self.resent_flows = set()
        if CONSISTENCY_INTERVAL > 0:
            self.execute_as_loop(CONSISTENCY_INTERVAL)

    def execute(self):
        """Run once on NApp 'start' or in a loop.

        The execute method is called by the run method of KytosNApp class.
        Users shouldn't call this method directly.
        """
        self._load_flows()

        if CONSISTENCY_INTERVAL > 0:
            self.consistency_check()

    def shutdown(self):
        """Shutdown routine of the NApp."""
        log.debug("flow-manager stopping")

    @listen_to('kytos/of_core.handshake.completed')
    def resend_stored_flows(self, event):
        """Resend stored Flows."""
        switch = event.content['switch']
        dpid = str(switch.dpid)
        # This can be a problem because this code is running a thread
        if dpid in self.resent_flows:
            log.debug(f'Flow already resent to the switch {dpid}')
            return
        if dpid in self.stored_flows:
            flow_list = self.stored_flows[dpid]['flow_list']
            for flow in flow_list:
                command = flow['command']
                flows_dict = {"flows": [flow['flow']]}
                self._install_flows(command, flows_dict, [switch])
            self.resent_flows.add(dpid)
            log.info(f'Flows resent to Switch {dpid}')

    def consistency_check(self):
        """Check the consistency of flows in each switch."""
        switches = self.controller.switches.values()

        for switch in switches:
            # Check if a dpid is a key in 'stored_flows' dictionary
            if switch.is_enabled():
                self.check_storehouse_consistency(switch)

                if switch.dpid in self.stored_flows:
                    self.check_switch_consistency(switch)

    def check_switch_consistency(self, switch):
        """Check consistency of installed flows for a specific switch."""
        dpid = switch.dpid

        # Flows stored in storehouse
        stored_flows = self.stored_flows[dpid]['flow_list']

        serializer = FlowFactory.get_class(switch)

        for stored_flow in stored_flows:
            command = stored_flow['command']
            stored_flow_obj = serializer.from_dict(stored_flow['flow'], switch)

            flow = {'flows': [stored_flow['flow']]}

            if stored_flow_obj not in switch.flows:
                if command == 'add':
                    log.info('A consistency problem was detected in '
                             f'switch {dpid}.')
                    self._install_flows(command, flow, [switch])
                    log.info(f'Flow forwarded to switch {dpid} to be '
                             'installed.')
            elif command == 'delete':
                log.info('A consistency problem was detected in '
                         f'switch {dpid}.')
                command = 'delete_strict'
                self._install_flows(command, flow, [switch])
                log.info(f'Flow forwarded to switch {dpid} to be deleted.')

    def check_storehouse_consistency(self, switch):
        """Check consistency of installed flows for a specific switch."""
        dpid = switch.dpid

        for installed_flow in switch.flows:
            if dpid not in self.stored_flows:
                log.info('A consistency problem was detected in '
                         f'switch {dpid}.')
                flow = {'flows': [installed_flow.as_dict()]}
                command = 'delete_strict'
                self._install_flows(command, flow, [switch])
                log.info(f'Flow forwarded to switch {dpid} to be deleted.')
            else:
                serializer = FlowFactory.get_class(switch)
                stored_flows = self.stored_flows[dpid]['flow_list']
                stored_flows_list = [serializer.from_dict(stored_flow['flow'],
                                                          switch)
                                     for stored_flow in stored_flows]

                if installed_flow not in stored_flows_list:
                    log.info('A consistency problem was detected in '
                             f'switch {dpid}.')
                    flow = {'flows': [installed_flow.as_dict()]}
                    command = 'delete_strict'
                    self._install_flows(command, flow, [switch])
                    log.info(f'Flow forwarded to switch {dpid} to be deleted.')

    # pylint: disable=attribute-defined-outside-init
    def _load_flows(self):
        """Load stored flows."""
        try:
            data = self.storehouse.get_data()['flow_persistence']
            if 'id' in data:
                del data['id']
            self.stored_flows = data
        except (KeyError, FileNotFoundError) as error:
            log.debug(f'There are no flows to load: {error}')
        else:
            log.info('Flows loaded.')

    def _store_changed_flows(self, command, flow, switch):
        """Store changed flows.

        Args:
            command: Flow command to be installed
            flow: Flows to be stored
            switch: Switch target
        """
        stored_flows_box = deepcopy(self.stored_flows)
        # if the flow has a destination dpid it can be stored.
        if not switch:
            log.info('The Flow cannot be stored, the destination switch '
                     f'have not been specified: {switch}')
            return
        installed_flow = {}
        flow_list = []
        installed_flow['command'] = command
        installed_flow['flow'] = flow
        deleted_flows = []

        serializer = FlowFactory.get_class(switch)
        installed_flow_obj = serializer.from_dict(flow, switch)

        if switch.id not in stored_flows_box:
            # Switch not stored, add to box.
            flow_list.append(installed_flow)
            stored_flows_box[switch.id] = {'flow_list': flow_list}
        else:
            stored_flows = stored_flows_box[switch.id].get('flow_list', [])
            # Check if flow already stored
            for stored_flow in stored_flows:
                stored_flow_obj = serializer.from_dict(stored_flow['flow'],
                                                       switch)

                version = switch.connection.protocol.version

                if installed_flow['command'] == 'delete':
                    # No strict match
                    if match_flow(flow, version, stored_flow['flow']):
                        deleted_flows.append(stored_flow)

                elif installed_flow_obj == stored_flow_obj:
                    if stored_flow['command'] == installed_flow['command']:
                        log.debug('Data already stored.')
                        return
                    # Flow with inconsistency in "command" fields : Remove the
                    # old instruction. This happens when there is a stored
                    # instruction to install the flow, but the new instruction
                    # is to remove it. In this case, the old instruction is
                    # removed and the new one is stored.
                    stored_flow['command'] = installed_flow.get('command')
                    deleted_flows.append(stored_flow)
                    break

            # if installed_flow['command'] != 'delete':
            stored_flows.append(installed_flow)
            for i in deleted_flows:
                stored_flows.remove(i)
            stored_flows_box[switch.id]['flow_list'] = stored_flows

        stored_flows_box['id'] = 'flow_persistence'
        self.storehouse.save_flow(stored_flows_box)
        del stored_flows_box['id']
        self.stored_flows = deepcopy(stored_flows_box)

    @rest('v2/flows')
    @rest('v2/flows/<dpid>')
    def list(self, dpid=None):
        """Retrieve all flows from a switch identified by dpid.

        If no dpid is specified, return all flows from all switches.
        """
        if dpid is None:
            switches = self.controller.switches.values()
        else:
            switches = [self.controller.get_switch_by_dpid(dpid)]

        switch_flows = {}

        for switch in switches:
            flows_dict = [flow.as_dict() for flow in switch.flows]
            switch_flows[switch.dpid] = {'flows': flows_dict}

        return jsonify(switch_flows)

    @rest('v2/flows', methods=['POST'])
    @rest('v2/flows/<dpid>', methods=['POST'])
    def add(self, dpid=None):
        """Install new flows in the switch identified by dpid.

        If no dpid is specified, install flows in all switches.
        """
        return self._send_flow_mods_from_request(dpid, "add")

    @rest('v2/delete', methods=['POST'])
    @rest('v2/delete/<dpid>', methods=['POST'])
    @rest('v2/flows', methods=['DELETE'])
    @rest('v2/flows/<dpid>', methods=['DELETE'])
    def delete(self, dpid=None):
        """Delete existing flows in the switch identified by dpid.

        If no dpid is specified, delete flows from all switches.
        """
        return self._send_flow_mods_from_request(dpid, "delete")

    def _get_all_switches_enabled(self):
        """Get a list of all switches enabled."""
        switches = self.controller.switches.values()
        return [switch for switch in switches if switch.is_enabled()]

    def _send_flow_mods_from_request(self, dpid, command, flows_dict=None):
        """Install FlowsMods from request."""
        if flows_dict is None:
            flows_dict = request.get_json()
            if flows_dict is None:
                return jsonify({"response": 'flows dict is none.'}), 404

        if dpid:
            switch = self.controller.get_switch_by_dpid(dpid)
            if not switch:
                return jsonify({"response": 'dpid not found.'}), 404
            elif switch.is_enabled() is False:
                if command == "delete":
                    self._install_flows(command, flows_dict, [switch])
                else:
                    return jsonify({"response": 'switch is disabled.'}), 404
            else:
                self._install_flows(command, flows_dict, [switch])
        else:
            self._install_flows(command, flows_dict,
                                self._get_all_switches_enabled())

        return jsonify({"response": "FlowMod Messages Sent"})

    def _install_flows(self, command, flows_dict, switches=[]):
        """Execute all procedures to install flows in the switches.

        Args:
            command: Flow command to be installed
            flows_dict: Dictionary with flows to be installed in the switches.
            switches: A list of switches
        """
        for switch in switches:
            serializer = FlowFactory.get_class(switch)
            flows = flows_dict.get('flows', [])
            for flow_dict in flows:
                flow = serializer.from_dict(flow_dict, switch)
                if command == "delete":
                    flow_mod = flow.as_of_delete_flow_mod()
                elif command == "delete_strict":
                    flow_mod = flow.as_of_strict_delete_flow_mod()
                elif command == "add":
                    flow_mod = flow.as_of_add_flow_mod()
                else:
                    raise InvalidCommandError
                self._send_flow_mod(flow.switch, flow_mod)
                self._add_flow_mod_sent(flow_mod.header.xid, flow, command)

                self._send_napp_event(switch, flow, command)
                self._store_changed_flows(command, flow_dict, switch)

    def _add_flow_mod_sent(self, xid, flow, command):
        """Add the flow mod to the list of flow mods sent."""
        if len(self._flow_mods_sent) >= self._flow_mods_sent_max_size:
            self._flow_mods_sent.popitem(last=False)
        self._flow_mods_sent[xid] = (flow, command)

    def _send_flow_mod(self, switch, flow_mod):
        event_name = 'kytos/flow_manager.messages.out.ofpt_flow_mod'

        content = {'destination': switch.connection,
                   'message': flow_mod}

        event = KytosEvent(name=event_name, content=content)
        self.controller.buffers.msg_out.put(event)

    def _send_napp_event(self, switch, flow, command, **kwargs):
        """Send an Event to other apps informing about a FlowMod."""
        if command == 'add':
            name = 'kytos/flow_manager.flow.added'
        elif command in ('delete', 'delete_strict'):
            name = 'kytos/flow_manager.flow.removed'
        elif command == 'error':
            name = 'kytos/flow_manager.flow.error'
        else:
            raise InvalidCommandError
        content = {'datapath': switch,
                   'flow': flow}
        content.update(kwargs)
        event_app = KytosEvent(name, content)
        self.controller.buffers.app.put(event_app)

    @listen_to('.*.of_core.*.ofpt_error')
    def handle_errors(self, event):
        """Receive OpenFlow error and send a event.

        The event is sent only if the error is related to a request made
        by flow_manager.
        """
        message = event.content["message"]

        connection = event.source
        switch = connection.switch

        xid = message.header.xid.value
        error_type = message.error_type
        error_code = message.code
        error_data = message.data.pack()

        # Get the packet responsible for the error
        error_packet = connection.protocol.unpack(error_data)

        if message.code == BadActionCode.OFPBAC_BAD_OUT_PORT:
            actions = []
            if hasattr(error_packet, 'actions'):
                # Get actions from the flow mod (OF 1.0)
                actions = error_packet.actions
            else:
                # Get actions from the list of flow mod instructions (OF 1.3)
                for instruction in error_packet.instructions:
                    actions.extend(instruction.actions)

            for action in actions:
                iface = switch.get_interface_by_port_no(action.port)

                # Set interface to drop packets forwarded to it
                if iface:
                    iface.config = PortConfig.OFPPC_NO_FWD

        try:
            flow, error_command = self._flow_mods_sent[xid]
        except KeyError:
            pass
        else:
            self._send_napp_event(flow.switch, flow, 'error',
                                  error_command=error_command,
                                  error_type=error_type, error_code=error_code)


1		"""kytos/flow_manager NApp installs, lists and deletes switch flows."""
2	1	from collections import OrderedDict
3	1	from copy import deepcopy
4
5	1	from flask import jsonify, request
6	1	from pyof.v0x01.asynchronous.error_msg import BadActionCode
7	1	from pyof.v0x01.common.phy_port import PortConfig
8
9	1	from kytos.core import KytosEvent, KytosNApp, log, rest
10	1	from kytos.core.helpers import listen_to
11	1	from napps.kytos.flow_manager.match import match_flow
12	1	from napps.kytos.flow_manager.storehouse import StoreHouse
13	1	from napps.kytos.of_core.flow import FlowFactory
14
15	1	from .exceptions import InvalidCommandError
16	1	from .settings import CONSISTENCY_INTERVAL, FLOWS_DICT_MAX_SIZE
17
18
19	1	class Main(KytosNApp):
20		"""Main class to be used by Kytos controller."""
21
22	1	def setup(self):
23		"""Replace the 'init' method for the KytosApp subclass.
24
25		The setup method is automatically called by the run method.
26		Users shouldn't call this method directly.
27		"""
28	1	log.debug("flow-manager starting")
29	1	self._flow_mods_sent = OrderedDict()
30	1	self._flow_mods_sent_max_size = FLOWS_DICT_MAX_SIZE
31
32		# Storehouse client to save and restore flow data:
33	1	self.storehouse = StoreHouse(self.controller)
34
35		# Format of stored flow data:
36		# {'flow_persistence': {'dpid_str': {'flow_list': [
37		# {'command': '<add\|delete>',
38		# 'flow': {flow_dict}}]}}}
39	1	self.stored_flows = {}
40	1	self.resent_flows = set()
41	1	if CONSISTENCY_INTERVAL > 0:
42	1	self.execute_as_loop(CONSISTENCY_INTERVAL)
43
44	1	def execute(self):
45		"""Run once on NApp 'start' or in a loop.
46
47		The execute method is called by the run method of KytosNApp class.
48		Users shouldn't call this method directly.
49		"""
50		self._load_flows()
51
52		if CONSISTENCY_INTERVAL > 0:
53		self.consistency_check()
54
55	1	def shutdown(self):
56		"""Shutdown routine of the NApp."""
57		log.debug("flow-manager stopping")
58
59	1	@listen_to('kytos/of_core.handshake.completed')
60		def resend_stored_flows(self, event):
61		"""Resend stored Flows."""
62	1	switch = event.content['switch']
63	1	dpid = str(switch.dpid)
64		# This can be a problem because this code is running a thread
65	1	if dpid in self.resent_flows:
66		log.debug(f'Flow already resent to the switch {dpid}')
67		return
68	1	if dpid in self.stored_flows:
69	1	flow_list = self.stored_flows[dpid]['flow_list']
70	1	for flow in flow_list:
71	1	command = flow['command']
72	1	flows_dict = {"flows": [flow['flow']]}
73	1	self._install_flows(command, flows_dict, [switch])
74	1	self.resent_flows.add(dpid)
75	1	log.info(f'Flows resent to Switch {dpid}')
76
77	1	def consistency_check(self):
78		"""Check the consistency of flows in each switch."""
79		switches = self.controller.switches.values()
80
81		for switch in switches:
82		# Check if a dpid is a key in 'stored_flows' dictionary
83		if switch.is_enabled():
84		self.check_storehouse_consistency(switch)
85
86		if switch.dpid in self.stored_flows:
87		self.check_switch_consistency(switch)
88
89	1	def check_switch_consistency(self, switch):
90		"""Check consistency of installed flows for a specific switch."""
91	1	dpid = switch.dpid
92
93		# Flows stored in storehouse
94	1	stored_flows = self.stored_flows[dpid]['flow_list']
95
96	1	serializer = FlowFactory.get_class(switch)
97
98	1	for stored_flow in stored_flows:
99	1	command = stored_flow['command']
100	1	stored_flow_obj = serializer.from_dict(stored_flow['flow'], switch)
101
102	1	flow = {'flows': [stored_flow['flow']]}
103
104	1	if stored_flow_obj not in switch.flows:
105	1	if command == 'add':
106	1	log.info('A consistency problem was detected in '
107		f'switch {dpid}.')
108	1	self._install_flows(command, flow, [switch])
109	1	log.info(f'Flow forwarded to switch {dpid} to be '
110		'installed.')
111	1	elif command == 'delete':
112	1	log.info('A consistency problem was detected in '
113		f'switch {dpid}.')
114	1	command = 'delete_strict'
115	1	self._install_flows(command, flow, [switch])
116	1	log.info(f'Flow forwarded to switch {dpid} to be deleted.')
117
118	1	def check_storehouse_consistency(self, switch):
119		"""Check consistency of installed flows for a specific switch."""
120	1	dpid = switch.dpid
121
122	1	for installed_flow in switch.flows:
123	1	if dpid not in self.stored_flows:
124		log.info('A consistency problem was detected in '
125		f'switch {dpid}.')
126		flow = {'flows': [installed_flow.as_dict()]}
127		command = 'delete_strict'
128		self._install_flows(command, flow, [switch])
129		log.info(f'Flow forwarded to switch {dpid} to be deleted.')
130		else:
131	1	serializer = FlowFactory.get_class(switch)
132	1	stored_flows = self.stored_flows[dpid]['flow_list']
133	1	stored_flows_list = [serializer.from_dict(stored_flow['flow'],
134		switch)
135		for stored_flow in stored_flows]
136
137	1	if installed_flow not in stored_flows_list:
138	1	log.info('A consistency problem was detected in '
139		f'switch {dpid}.')
140	1	flow = {'flows': [installed_flow.as_dict()]}
141	1	command = 'delete_strict'
142	1	self._install_flows(command, flow, [switch])
143	1	log.info(f'Flow forwarded to switch {dpid} to be deleted.')
144
145		# pylint: disable=attribute-defined-outside-init
146	1	def _load_flows(self):
147		"""Load stored flows."""
148	1	try:
149	1	data = self.storehouse.get_data()['flow_persistence']
150	1	if 'id' in data:
151		del data['id']
152	1	self.stored_flows = data
153		except (KeyError, FileNotFoundError) as error:
154		log.debug(f'There are no flows to load: {error}')
155		else:
156	1	log.info('Flows loaded.')
157
158	1	def _store_changed_flows(self, command, flow, switch):
159		"""Store changed flows.
160
161		Args:
162		command: Flow command to be installed
163		flow: Flows to be stored
164		switch: Switch target
165		"""
166	1	stored_flows_box = deepcopy(self.stored_flows)
167		# if the flow has a destination dpid it can be stored.
168	1	if not switch:
169		log.info('The Flow cannot be stored, the destination switch '
170		f'have not been specified: {switch}')
171		return
172	1	installed_flow = {}
173	1	flow_list = []
174	1	installed_flow['command'] = command
175	1	installed_flow['flow'] = flow
176	1	deleted_flows = []
177
178	1	serializer = FlowFactory.get_class(switch)
179	1	installed_flow_obj = serializer.from_dict(flow, switch)
180
181	1	if switch.id not in stored_flows_box:
182		# Switch not stored, add to box.
183	1	flow_list.append(installed_flow)
184	1	stored_flows_box[switch.id] = {'flow_list': flow_list}
185		else:
186	1	stored_flows = stored_flows_box[switch.id].get('flow_list', [])
187		# Check if flow already stored
188	1	for stored_flow in stored_flows:
189	1	stored_flow_obj = serializer.from_dict(stored_flow['flow'],
190		switch)
191
192	1	version = switch.connection.protocol.version
193
194	1	if installed_flow['command'] == 'delete':
195		# No strict match
196	1	if match_flow(flow, version, stored_flow['flow']):
197	1	deleted_flows.append(stored_flow)
198
199	1	elif installed_flow_obj == stored_flow_obj:
200	1	if stored_flow['command'] == installed_flow['command']:
201		log.debug('Data already stored.')
202		return
203		# Flow with inconsistency in "command" fields : Remove the
204		# old instruction. This happens when there is a stored
205		# instruction to install the flow, but the new instruction
206		# is to remove it. In this case, the old instruction is
207		# removed and the new one is stored.
208	1	stored_flow['command'] = installed_flow.get('command')
209	1	deleted_flows.append(stored_flow)
210	1	break
211
212		# if installed_flow['command'] != 'delete':
213	1	stored_flows.append(installed_flow)
214	1	for i in deleted_flows:
215	1	stored_flows.remove(i)
216	1	stored_flows_box[switch.id]['flow_list'] = stored_flows
217
218	1	stored_flows_box['id'] = 'flow_persistence'
219	1	self.storehouse.save_flow(stored_flows_box)
220	1	del stored_flows_box['id']
221	1	self.stored_flows = deepcopy(stored_flows_box)
222
223	1	@rest('v2/flows')
224	1	@rest('v2/flows/<dpid>')
225	1	def list(self, dpid=None):
226		"""Retrieve all flows from a switch identified by dpid.
227
228		If no dpid is specified, return all flows from all switches.
229		"""
230	1	if dpid is None:
231	1	switches = self.controller.switches.values()
232		else:
233	1	switches = [self.controller.get_switch_by_dpid(dpid)]
234
235	1	switch_flows = {}
236
237	1	for switch in switches:
238	1	flows_dict = [flow.as_dict() for flow in switch.flows]
239	1	switch_flows[switch.dpid] = {'flows': flows_dict}
240
241	1	return jsonify(switch_flows)
242
243	1	@rest('v2/flows', methods=['POST'])
244	1	@rest('v2/flows/<dpid>', methods=['POST'])
245	1	def add(self, dpid=None):
246		"""Install new flows in the switch identified by dpid.
247
248		If no dpid is specified, install flows in all switches.
249		"""
250	1	return self._send_flow_mods_from_request(dpid, "add")
251
252	1	@rest('v2/delete', methods=['POST'])
253	1	@rest('v2/delete/<dpid>', methods=['POST'])
254	1	@rest('v2/flows', methods=['DELETE'])
255	1	@rest('v2/flows/<dpid>', methods=['DELETE'])
256	1	def delete(self, dpid=None):
257		"""Delete existing flows in the switch identified by dpid.
258
259		If no dpid is specified, delete flows from all switches.
260		"""
261	1	return self._send_flow_mods_from_request(dpid, "delete")
262
263	1	def _get_all_switches_enabled(self):
264		"""Get a list of all switches enabled."""
265	1	switches = self.controller.switches.values()
266	1	return [switch for switch in switches if switch.is_enabled()]
267
268	1	def _send_flow_mods_from_request(self, dpid, command, flows_dict=None):
269		"""Install FlowsMods from request."""
270	1	if flows_dict is None:
271	1	flows_dict = request.get_json()
272	1	if flows_dict is None:
273	1	return jsonify({"response": 'flows dict is none.'}), 404
274
275	1	if dpid:
276	1	switch = self.controller.get_switch_by_dpid(dpid)
277	1	if not switch:
278	1	return jsonify({"response": 'dpid not found.'}), 404
279	1	elif switch.is_enabled() is False:
280	1	if command == "delete":
281	1	self._install_flows(command, flows_dict, [switch])
282		else:
283	1	return jsonify({"response": 'switch is disabled.'}), 404
284		else:
285	1	self._install_flows(command, flows_dict, [switch])
286		else:
287	1	self._install_flows(command, flows_dict,
288		self._get_all_switches_enabled())
289
290	1	return jsonify({"response": "FlowMod Messages Sent"})
291
292	1	def _install_flows(self, command, flows_dict, switches=[]):
293		"""Execute all procedures to install flows in the switches.
294
295		Args:
296		command: Flow command to be installed
297		flows_dict: Dictionary with flows to be installed in the switches.
298		switches: A list of switches
299		"""
300	1	for switch in switches:
301	1	serializer = FlowFactory.get_class(switch)
302	1	flows = flows_dict.get('flows', [])
303	1	for flow_dict in flows:
304	1	flow = serializer.from_dict(flow_dict, switch)
305	1	if command == "delete":
306		flow_mod = flow.as_of_delete_flow_mod()
307	1	elif command == "delete_strict":
308	1	flow_mod = flow.as_of_strict_delete_flow_mod()
309	1	elif command == "add":
310	1	flow_mod = flow.as_of_add_flow_mod()
311		else:
312		raise InvalidCommandError
313	1	self._send_flow_mod(flow.switch, flow_mod)
314	1	self._add_flow_mod_sent(flow_mod.header.xid, flow, command)
315
316	1	self._send_napp_event(switch, flow, command)
317	1	self._store_changed_flows(command, flow_dict, switch)
318
319	1	def _add_flow_mod_sent(self, xid, flow, command):
320		"""Add the flow mod to the list of flow mods sent."""
321	1	if len(self._flow_mods_sent) >= self._flow_mods_sent_max_size:
322		self._flow_mods_sent.popitem(last=False)
323	1	self._flow_mods_sent[xid] = (flow, command)
324
325	1	def _send_flow_mod(self, switch, flow_mod):
326	1	event_name = 'kytos/flow_manager.messages.out.ofpt_flow_mod'
327
328	1	content = {'destination': switch.connection,
329		'message': flow_mod}
330
331	1	event = KytosEvent(name=event_name, content=content)
332	1	self.controller.buffers.msg_out.put(event)
333
334	1	def _send_napp_event(self, switch, flow, command, **kwargs):
335		"""Send an Event to other apps informing about a FlowMod."""
336	1	if command == 'add':
337	1	name = 'kytos/flow_manager.flow.added'
338	1	elif command in ('delete', 'delete_strict'):
339	1	name = 'kytos/flow_manager.flow.removed'
340	1	elif command == 'error':
341	1	name = 'kytos/flow_manager.flow.error'
342		else:
343		raise InvalidCommandError
344	1	content = {'datapath': switch,
345		'flow': flow}
346	1	content.update(kwargs)
347	1	event_app = KytosEvent(name, content)
348	1	self.controller.buffers.app.put(event_app)
349
350	1	@listen_to('..of_core..ofpt_error')
351		def handle_errors(self, event):
352		"""Receive OpenFlow error and send a event.
353
354		The event is sent only if the error is related to a request made
355		by flow_manager.
356		"""
357	1	message = event.content["message"]
358
359	1	connection = event.source
360	1	switch = connection.switch
361
362	1	xid = message.header.xid.value
363	1	error_type = message.error_type
364	1	error_code = message.code
365	1	error_data = message.data.pack()
366
367		# Get the packet responsible for the error
368	1	error_packet = connection.protocol.unpack(error_data)
369
370	1	if message.code == BadActionCode.OFPBAC_BAD_OUT_PORT:
371		actions = []
372		if hasattr(error_packet, 'actions'):
373		# Get actions from the flow mod (OF 1.0)
374		actions = error_packet.actions
375		else:
376		# Get actions from the list of flow mod instructions (OF 1.3)
377		for instruction in error_packet.instructions:
378		actions.extend(instruction.actions)
379
380		for action in actions:
381		iface = switch.get_interface_by_port_no(action.port)
382
383		# Set interface to drop packets forwarded to it
384		if iface:
385		iface.config = PortConfig.OFPPC_NO_FWD
386
387	1	try:
388	1	flow, error_command = self._flow_mods_sent[xid]
389		except KeyError:
390		pass
391		else:
392	1	self._send_napp_event(flow.switch, flow, 'error',
393		error_command=error_command,
394		error_type=error_type, error_code=error_code)
395

kytos / flow_manager

Pull Request — master (#117)

build.main.Main._send_flow_mods_from_request() B

Complexity

Size

Duplication

Code Coverage

Importance

Duplication Side-by-Side

Filter issues like