build.main.Main._send_flow_mod() - Code Metrics - Inspection of "Add consistency" - kytos/flow_manager - Measure and Improve Code Quality continuously with Scrutinizer

Test Failed

Pull Request — master (#96)

by Jose

created 2020-12-18 15:40 UTC

build.main.Main._send_flow_mod() A

↳ Parent: build.main

Complexity

Conditions

Size

Total Lines	8
Code Lines	6

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	0
CRAP Score	2

Importance

Changes

Metric	Value
cc	1
eloc	6
nop	3
dl	0
loc	8
rs	10
c	0
b	0
f	0
ccs	0
cts	0
cp	0
crap	2

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

from flask import jsonify, request

from kytos.core import KytosEvent, KytosNApp, log, rest
from kytos.core.helpers import listen_to
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:
            print("executou uma checagem de consistencia")
            self.consistency_check()

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

    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.dpid in self.stored_flows:
                print("iterando sobre os switches")
                self.check_switch_consistency(switch)
                # self.check_storehouse_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 not stored_flow_obj in switch.flows:
                log.info('A problem with consistency were dectected.')
                if command == 'add':
                    self._install_flows(command, flow, [switch])
                    log.info(f'Flow forwarded to switch {dpid} to be '
                             'installed.')
            elif command == 'delete':
                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

        serializer = FlowFactory.get_class(switch)
        stored_flow = self.stored_flows[dpid]['flow_list']
        stored_flows_list = [serializer.from_dict(stored_flow['flow'], switch)
                             for stored_flow in stored_flow]

        for installed_flow in switch.flows:
            if not installed_flow in stored_flows_list:
                log.info('A problem with consistency were dectected.')
                flow = {'flows': [installed_flow.as_dict()]}
                command = 'delete'
                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 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 = self.stored_flows.copy()
        # 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

        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)
                if 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')
                    stored_flows.remove(stored_flow)
                    break

            stored_flows.append(installed_flow)
            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 = stored_flows_box.copy()

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

kytos / flow_manager

Pull Request — master (#96)

build.main.Main._send_flow_mod() A

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