Lock with resources.py

import salabim as sim

left = -1
right = +1


def sidename(side):
    return 'l' if side == left else 'r'


class Shipgenerator(sim.Component):

    def process(self):
        while True:
            yield self.hold(sim.Exponential(iat).sample())
            ship = Ship(name=sidename(self.side) + 'ship.')
            ship.side = self.side
            ship.length = meanlength * sim.Uniform(2 / 3, 4 / 3).sample()
            if lock.mode() == 'Idle':
                lock.activate()


class Ship(sim.Component):
    def process(self):
        if lock.ispassive():
            lock.activate()
        yield self.request((lockmeters[self.side], self.length), key_in[self.side])
        self.enter(lockqueue)
        yield self.hold(intime)
        self.release(key_in[self.side])
        yield self.request(key_out)
        yield self.hold(outtime)
        self.leave(lockqueue)
        self.release(key_out)


class Lock(sim.Component):

    def process(self):
        yield self.request(key_in[left])
        yield self.request(key_in[right])
        yield self.request(key_out)

        while True:
            if len(key_in[self.side].requesters()) == 0:
                if len(key_in[-self.side].requesters()) == 0:
                    yield self.passivate()
            self.release(key_in[self.side])
            yield self.request((key_in[self.side], 1, 1000))
            lockmeters[self.side].release()
            yield self.hold(switchtime, mode='Switch')
            self.side = -self.side
            self.release(key_out)
            yield self.request((key_out, 1, 1000), mode=None)


env = sim.Environment(trace=True)

locklength = 60
switchtime = 10
intime = 2
outtime = 2
meanlength = 30
iat = 30

lockmeters = {}
key_in = {}
lockqueue = sim.Queue('lockqueue')
key_out = sim.Resource(name='key_out')

for side in (left, right):
    lockmeters[side] = sim.Resource(capacity=locklength, name=sidename(
        side) + ' lock meters', anonymous=True)
    key_in[side] = sim.Resource(name=sidename(side) + ' key in')
    shipgenerator = Shipgenerator(name=sidename(side) + 'Shipgenerator')
    shipgenerator.side = side

lock = Lock(name='lock')
lock.side = left

env.run(100)

for side in (left, right):
    lockmeters[side].print_statistics()