
# Copyright 2017-present Open Networking Foundation
#
# 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.


"""
Flow expire test case.
Similar to Flow expire test case in the perl test harness.

"""

import logging

import unittest
import random

from oftest import config
import oftest.controller as controller
import ofp
import oftest.dataplane as dataplane
import oftest.parse as parse
import oftest.base_tests as base_tests

from oftest.testutils import *
from time import sleep

class FlowExpire(base_tests.SimpleDataPlane):
    """
    Verify flow expire messages are properly generated.

    Generate a packet
    Generate and install a matching flow with idle timeout = 1 sec
    Verify the flow expiration message is received
    """
    def runTest(self):
        # TODO: set from command-line parameter
        test_timeout = 60

        of_ports = config["port_map"].keys()
        of_ports.sort()
        self.assertTrue(len(of_ports) > 1, "Not enough ports for test")

        delete_all_flows(self.controller)

        pkt = simple_tcp_packet()
        match = packet_to_flow_match(self, pkt)
        match.wildcards &= ~ofp.OFPFW_IN_PORT
        self.assertTrue(match is not None, 
                        "Could not generate flow match from pkt")
        act = ofp.action.output()

        of_ports = config["port_map"].keys()
        of_ports.sort()
        self.assertTrue(len(of_ports) > 1, "Not enough ports for test")

        ingress_port = of_ports[0]
        egress_port  = of_ports[1]
        logging.info("Ingress " + str(ingress_port) + 
                       " to egress " + str(egress_port))
        
        match.in_port = ingress_port
        
        request = ofp.message.flow_add()
        request.match = match
        request.cookie = random.randint(0,9007199254740992)
        request.buffer_id = 0xffffffff
        request.idle_timeout = 1
        request.flags |= ofp.OFPFF_SEND_FLOW_REM
        act.port = egress_port
        request.actions.append(act)
        
        logging.info("Inserting flow")
        self.controller.message_send(request)
        do_barrier(self.controller)

        (response, pkt) = self.controller.poll(exp_msg=ofp.OFPT_FLOW_REMOVED,
                                               timeout=test_timeout)

        self.assertTrue(response is not None, 
                        'Did not receive flow removed message ')

        self.assertEqual(request.cookie, response.cookie,
                         'Cookies do not match')

        self.assertEqual(ofp.OFPRR_IDLE_TIMEOUT, response.reason,
                         'Flow table entry removal reason is not idle_timeout')

        self.assertEqual(match, response.match,
                         'Flow table entry does not match')
        
        sleep(1)