# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Test code for policies.
"""
from __future__ import division, absolute_import

from zope.interface import Interface, implementer, implementedBy

from twisted.python.compat import NativeStringIO, _PY3
from twisted.trial import unittest
from twisted.test.proto_helpers import StringTransport
from twisted.test.proto_helpers import StringTransportWithDisconnection

from twisted.internet import protocol, reactor, address, defer, task
from twisted.protocols import policies



class SimpleProtocol(protocol.Protocol):

connected = disconnected = 0
buffer = b""

def __init__(self):
self.dConnected = defer.Deferred()
self.dDisconnected = defer.Deferred()

def connectionMade(self):
self.connected = 1
self.dConnected.callback('')

def connectionLost(self, reason):
self.disconnected = 1
self.dDisconnected.callback('')

def dataReceived(self, data):
self.buffer += data



class SillyFactory(protocol.ClientFactory):

def __init__(self, p):
self.p = p

def buildProtocol(self, addr):
return self.p


class EchoProtocol(protocol.Protocol):
paused = False

def pauseProducing(self):
self.paused = True

def resumeProducing(self):
self.paused = False

def stopProducing(self):
pass

def dataReceived(self, data):
self.transport.write(data)



class Server(protocol.ServerFactory):
"""
A simple server factory using L{EchoProtocol}.
"""
protocol = EchoProtocol



class TestableThrottlingFactory(policies.ThrottlingFactory):
"""
L{policies.ThrottlingFactory} using a L{task.Clock} for tests.
"""

def __init__(self, clock, *args, **kwargs):
"""
@param clock: object providing a callLater method that can be used
for tests.
@type clock: C{task.Clock} or alike.
"""
policies.ThrottlingFactory.__init__(self, *args, **kwargs)
self.clock = clock


def callLater(self, period, func):
"""
Forward to the testable clock.
"""
return self.clock.callLater(period, func)



class TestableTimeoutFactory(policies.TimeoutFactory):
"""
L{policies.TimeoutFactory} using a L{task.Clock} for tests.
"""

def __init__(self, clock, *args, **kwargs):
"""
@param clock: object providing a callLater method that can be used
for tests.
@type clock: C{task.Clock} or alike.
"""
policies.TimeoutFactory.__init__(self, *args, **kwargs)
self.clock = clock


def callLater(self, period, func):
"""
Forward to the testable clock.
"""
return self.clock.callLater(period, func)



class WrapperTestCase(unittest.TestCase):
"""
Tests for L{WrappingFactory} and L{ProtocolWrapper}.
"""
def test_protocolFactoryAttribute(self):
"""
Make sure protocol.factory is the wrapped factory, not the wrapping
factory.
"""
f = Server()
wf = policies.WrappingFactory(f)
p = wf.buildProtocol(address.IPv4Address('TCP', '127.0.0.1', 35))
self.assertIdentical(p.wrappedProtocol.factory, f)


def test_transportInterfaces(self):
"""
The transport wrapper passed to the wrapped protocol's
C{makeConnection} provides the same interfaces as are provided by the
original transport.
"""
class IStubTransport(Interface):
pass

@implementer(IStubTransport)
class StubTransport:
pass

# Looking up what ProtocolWrapper implements also mutates the class.
# It adds __implemented__ and __providedBy__ attributes to it. These
# prevent __getattr__ from causing the IStubTransport.providedBy call
# below from returning True. If, by accident, nothing else causes
# these attributes to be added to ProtocolWrapper, the test will pass,
# but the interface will only be provided until something does trigger
# their addition. So we just trigger it right now to be sure.
implementedBy(policies.ProtocolWrapper)

proto = protocol.Protocol()
wrapper = policies.ProtocolWrapper(policies.WrappingFactory(None), proto)

wrapper.makeConnection(StubTransport())
self.assertTrue(IStubTransport.providedBy(proto.transport))


def test_factoryLogPrefix(self):
"""
L{WrappingFactory.logPrefix} is customized to mention both the original
factory and the wrapping factory.
"""
server = Server()
factory = policies.WrappingFactory(server)
self.assertEqual("Server (WrappingFactory)", factory.logPrefix())


def test_factoryLogPrefixFallback(self):
"""
If the wrapped factory doesn't have a L{logPrefix} method,
L{WrappingFactory.logPrefix} falls back to the factory class name.
"""
class NoFactory(object):
pass

server = NoFactory()
factory = policies.WrappingFactory(server)
self.assertEqual("NoFactory (WrappingFactory)", factory.logPrefix())


def test_protocolLogPrefix(self):
"""
L{ProtocolWrapper.logPrefix} is customized to mention both the original
protocol and the wrapper.
"""
server = Server()
factory = policies.WrappingFactory(server)
protocol = factory.buildProtocol(
address.IPv4Address('TCP', '127.0.0.1', 35))
self.assertEqual("EchoProtocol (ProtocolWrapper)",
protocol.logPrefix())


def test_protocolLogPrefixFallback(self):
"""
If the wrapped protocol doesn't have a L{logPrefix} method,
L{ProtocolWrapper.logPrefix} falls back to the protocol class name.
"""
class NoProtocol(object):
pass

server = Server()
server.protocol = NoProtocol
factory = policies.WrappingFactory(server)
protocol = factory.buildProtocol(
address.IPv4Address('TCP', '127.0.0.1', 35))
self.assertEqual("NoProtocol (ProtocolWrapper)",
protocol.logPrefix())


def _getWrapper(self):
"""
Return L{policies.ProtocolWrapper} that has been connected to a
L{StringTransport}.
"""
wrapper = policies.ProtocolWrapper(policies.WrappingFactory(Server()),
protocol.Protocol())
transport = StringTransport()
wrapper.makeConnection(transport)
return wrapper


def test_getHost(self):
"""
L{policies.ProtocolWrapper.getHost} calls C{getHost} on the underlying
transport.
"""
wrapper = self._getWrapper()
self.assertEqual(wrapper.getHost(), wrapper.transport.getHost())


def test_getPeer(self):
"""
L{policies.ProtocolWrapper.getPeer} calls C{getPeer} on the underlying
transport.
"""
wrapper = self._getWrapper()
self.assertEqual(wrapper.getPeer(), wrapper.transport.getPeer())


def test_registerProducer(self):
"""
L{policies.ProtocolWrapper.registerProducer} calls C{registerProducer}
on the underlying transport.
"""
wrapper = self._getWrapper()
producer = object()
wrapper.registerProducer(producer, True)
self.assertIdentical(wrapper.transport.producer, producer)
self.assertTrue(wrapper.transport.streaming)


def test_unregisterProducer(self):
"""
L{policies.ProtocolWrapper.unregisterProducer} calls
C{unregisterProducer} on the underlying transport.
"""
wrapper = self._getWrapper()
producer = object()
wrapper.registerProducer(producer, True)
wrapper.unregisterProducer()
self.assertIdentical(wrapper.transport.producer, None)
self.assertIdentical(wrapper.transport.streaming, None)


def test_stopConsuming(self):
"""
L{policies.ProtocolWrapper.stopConsuming} calls C{stopConsuming} on
the underlying transport.
"""
wrapper = self._getWrapper()
result = []
wrapper.transport.stopConsuming = lambda: result.append(True)
wrapper.stopConsuming()
self.assertEqual(result, [True])


def test_startedConnecting(self):
"""
L{policies.WrappingFactory.startedConnecting} calls
C{startedConnecting} on the underlying factory.
"""
result = []
class Factory(object):
def startedConnecting(self, connector):
result.append(connector)

wrapper = policies.WrappingFactory(Factory())
connector = object()
wrapper.startedConnecting(connector)
self.assertEqual(result, [connector])


def test_clientConnectionLost(self):
"""
L{policies.WrappingFactory.clientConnectionLost} calls
C{clientConnectionLost} on the underlying factory.
"""
result = []
class Factory(object):
def clientConnectionLost(self, connector, reason):
result.append((connector, reason))

wrapper = policies.WrappingFactory(Factory())
connector = object()
reason = object()
wrapper.clientConnectionLost(connector, reason)
self.assertEqual(result, [(connector, reason)])


def test_clientConnectionFailed(self):
"""
L{policies.WrappingFactory.clientConnectionFailed} calls
C{clientConnectionFailed} on the underlying factory.
"""
result = []
class Factory(object):
def clientConnectionFailed(self, connector, reason):
result.append((connector, reason))

wrapper = policies.WrappingFactory(Factory())
connector = object()
reason = object()
wrapper.clientConnectionFailed(connector, reason)
self.assertEqual(result, [(connector, reason)])



class WrappingFactory(policies.WrappingFactory):
protocol = lambda s, f, p: p

def startFactory(self):
policies.WrappingFactory.startFactory(self)
self.deferred.callback(None)



class ThrottlingTestCase(unittest.TestCase):
"""
Tests for L{policies.ThrottlingFactory}.
"""

def test_limit(self):
"""
Full test using a custom server limiting number of connections.
"""
server = Server()
c1, c2, c3, c4 = [SimpleProtocol() for i in range(4)]
tServer = policies.ThrottlingFactory(server, 2)
wrapTServer = WrappingFactory(tServer)
wrapTServer.deferred = defer.Deferred()

# Start listening
p = reactor.listenTCP(0, wrapTServer, interface="127.0.0.1")
n = p.getHost().port

def _connect123(results):
reactor.connectTCP("127.0.0.1", n, SillyFactory(c1))
c1.dConnected.addCallback(
lambda r: reactor.connectTCP("127.0.0.1", n, SillyFactory(c2)))
c2.dConnected.addCallback(
lambda r: reactor.connectTCP("127.0.0.1", n, SillyFactory(c3)))
return c3.dDisconnected

def _check123(results):
self.assertEqual([c.connected for c in (c1, c2, c3)], [1, 1, 1])
self.assertEqual([c.disconnected for c in (c1, c2, c3)], [0, 0, 1])
self.assertEqual(len(tServer.protocols.keys()), 2)
return results

def _lose1(results):
# disconnect one protocol and now another should be able to connect
c1.transport.loseConnection()
return c1.dDisconnected

def _connect4(results):
reactor.connectTCP("127.0.0.1", n, SillyFactory(c4))
return c4.dConnected

def _check4(results):
self.assertEqual(c4.connected, 1)
self.assertEqual(c4.disconnected, 0)
return results

def _cleanup(results):
for c in c2, c4:
c.transport.loseConnection()
return defer.DeferredList([
defer.maybeDeferred(p.stopListening),
c2.dDisconnected,
c4.dDisconnected])

wrapTServer.deferred.addCallback(_connect123)
wrapTServer.deferred.addCallback(_check123)
wrapTServer.deferred.addCallback(_lose1)
wrapTServer.deferred.addCallback(_connect4)
wrapTServer.deferred.addCallback(_check4)
wrapTServer.deferred.addCallback(_cleanup)
return wrapTServer.deferred


def test_writeLimit(self):
"""
Check the writeLimit parameter: write data, and check for the pause
status.
"""
server = Server()
tServer = TestableThrottlingFactory(task.Clock(), server, writeLimit=10)
port = tServer.buildProtocol(address.IPv4Address('TCP', '127.0.0.1', 0))
tr = StringTransportWithDisconnection()
tr.protocol = port
port.makeConnection(tr)
port.producer = port.wrappedProtocol

port.dataReceived(b"0123456789")
port.dataReceived(b"abcdefghij")
self.assertEqual(tr.value(), b"0123456789abcdefghij")
self.assertEqual(tServer.writtenThisSecond, 20)
self.assertFalse(port.wrappedProtocol.paused)

# at this point server should've written 20 bytes, 10 bytes
# above the limit so writing should be paused around 1 second
# from 'now', and resumed a second after that
tServer.clock.advance(1.05)
self.assertEqual(tServer.writtenThisSecond, 0)
self.assertTrue(port.wrappedProtocol.paused)

tServer.clock.advance(1.05)
self.assertEqual(tServer.writtenThisSecond, 0)
self.assertFalse(port.wrappedProtocol.paused)


def test_readLimit(self):
"""
Check the readLimit parameter: read data and check for the pause
status.
"""
server = Server()
tServer = TestableThrottlingFactory(task.Clock(), server, readLimit=10)
port = tServer.buildProtocol(address.IPv4Address('TCP', '127.0.0.1', 0))
tr = StringTransportWithDisconnection()
tr.protocol = port
port.makeConnection(tr)

port.dataReceived(b"0123456789")
port.dataReceived(b"abcdefghij")
self.assertEqual(tr.value(), b"0123456789abcdefghij")
self.assertEqual(tServer.readThisSecond, 20)

tServer.clock.advance(1.05)
self.assertEqual(tServer.readThisSecond, 0)
self.assertEqual(tr.producerState, 'paused')

tServer.clock.advance(1.05)
self.assertEqual(tServer.readThisSecond, 0)
self.assertEqual(tr.producerState, 'producing')

tr.clear()
port.dataReceived(b"0123456789")
port.dataReceived(b"abcdefghij")
self.assertEqual(tr.value(), b"0123456789abcdefghij")
self.assertEqual(tServer.readThisSecond, 20)

tServer.clock.advance(1.05)
self.assertEqual(tServer.readThisSecond, 0)
self.assertEqual(tr.producerState, 'paused')

tServer.clock.advance(1.05)
self.assertEqual(tServer.readThisSecond, 0)
self.assertEqual(tr.producerState, 'producing')



class TimeoutTestCase(unittest.TestCase):
"""
Tests for L{policies.TimeoutFactory}.
"""

def setUp(self):
"""
Create a testable, deterministic clock, and a set of
server factory/protocol/transport.
"""
self.clock = task.Clock()
wrappedFactory = protocol.ServerFactory()
wrappedFactory.protocol = SimpleProtocol
self.factory = TestableTimeoutFactory(self.clock, wrappedFactory, 3)
self.proto = self.factory.buildProtocol(
address.IPv4Address('TCP', '127.0.0.1', 12345))
self.transport = StringTransportWithDisconnection()
self.transport.protocol = self.proto
self.proto.makeConnection(self.transport)


def test_timeout(self):
"""
Make sure that when a TimeoutFactory accepts a connection, it will
time out that connection if no data is read or written within the
timeout period.
"""
# Let almost 3 time units pass
self.clock.pump([0.0, 0.5, 1.0, 1.0, 0.4])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Now let the timer elapse
self.clock.pump([0.0, 0.2])
self.failUnless(self.proto.wrappedProtocol.disconnected)


def test_sendAvoidsTimeout(self):
"""
Make sure that writing data to a transport from a protocol
constructed by a TimeoutFactory resets the timeout countdown.
"""
# Let half the countdown period elapse
self.clock.pump([0.0, 0.5, 1.0])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Send some data (self.proto is the /real/ proto's transport, so this
# is the write that gets called)
self.proto.write(b'bytes bytes bytes')

# More time passes, putting us past the original timeout
self.clock.pump([0.0, 1.0, 1.0])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Make sure writeSequence delays timeout as well
self.proto.writeSequence([b'bytes'] * 3)

# Tick tock
self.clock.pump([0.0, 1.0, 1.0])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Don't write anything more, just let the timeout expire
self.clock.pump([0.0, 2.0])
self.failUnless(self.proto.wrappedProtocol.disconnected)


def test_receiveAvoidsTimeout(self):
"""
Make sure that receiving data also resets the timeout countdown.
"""
# Let half the countdown period elapse
self.clock.pump([0.0, 1.0, 0.5])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Some bytes arrive, they should reset the counter
self.proto.dataReceived(b'bytes bytes bytes')

# We pass the original timeout
self.clock.pump([0.0, 1.0, 1.0])
self.failIf(self.proto.wrappedProtocol.disconnected)

# Nothing more arrives though, the new timeout deadline is passed,
# the connection should be dropped.
self.clock.pump([0.0, 1.0, 1.0])
self.failUnless(self.proto.wrappedProtocol.disconnected)



class TimeoutTester(protocol.Protocol, policies.TimeoutMixin):
"""
A testable protocol with timeout facility.

@ivar timedOut: set to C{True} if a timeout has been detected.
@type timedOut: C{bool}
"""
timeOut = 3
timedOut = False

def __init__(self, clock):
"""
Initialize the protocol with a C{task.Clock} object.
"""
self.clock = clock


def connectionMade(self):
"""
Upon connection, set the timeout.
"""
self.setTimeout(self.timeOut)


def dataReceived(self, data):
"""
Reset the timeout on data.
"""
self.resetTimeout()
protocol.Protocol.dataReceived(self, data)


def connectionLost(self, reason=None):
"""
On connection lost, cancel all timeout operations.
"""
self.setTimeout(None)


def timeoutConnection(self):
"""
Flags the timedOut variable to indicate the timeout of the connection.
"""
self.timedOut = True


def callLater(self, timeout, func, *args, **kwargs):
"""
Override callLater to use the deterministic clock.
"""
return self.clock.callLater(timeout, func, *args, **kwargs)



class TestTimeout(unittest.TestCase):
"""
Tests for L{policies.TimeoutMixin}.
"""

def setUp(self):
"""
Create a testable, deterministic clock and a C{TimeoutTester} instance.
"""
self.clock = task.Clock()
self.proto = TimeoutTester(self.clock)


def test_overriddenCallLater(self):
"""
Test that the callLater of the clock is used instead of
C{reactor.callLater}.
"""
self.proto.setTimeout(10)
self.assertEqual(len(self.clock.calls), 1)


def test_timeout(self):
"""
Check that the protocol does timeout at the time specified by its
C{timeOut} attribute.
"""
self.proto.makeConnection(StringTransport())

# timeOut value is 3
self.clock.pump([0, 0.5, 1.0, 1.0])
self.failIf(self.proto.timedOut)
self.clock.pump([0, 1.0])
self.failUnless(self.proto.timedOut)


def test_noTimeout(self):
"""
Check that receiving data is delaying the timeout of the connection.
"""
self.proto.makeConnection(StringTransport())

self.clock.pump([0, 0.5, 1.0, 1.0])
self.failIf(self.proto.timedOut)
self.proto.dataReceived(b'hello there')
self.clock.pump([0, 1.0, 1.0, 0.5])
self.failIf(self.proto.timedOut)
self.clock.pump([0, 1.0])
self.failUnless(self.proto.timedOut)


def test_resetTimeout(self):
"""
Check that setting a new value for timeout cancel the previous value
and install a new timeout.
"""
self.proto.timeOut = None
self.proto.makeConnection(StringTransport())

self.proto.setTimeout(1)
self.assertEqual(self.proto.timeOut, 1)

self.clock.pump([0, 0.9])
self.failIf(self.proto.timedOut)
self.clock.pump([0, 0.2])
self.failUnless(self.proto.timedOut)


def test_cancelTimeout(self):
"""
Setting the timeout to C{None} cancel any timeout operations.
"""
self.proto.timeOut = 5
self.proto.makeConnection(StringTransport())

self.proto.setTimeout(None)
self.assertEqual(self.proto.timeOut, None)

self.clock.pump([0, 5, 5, 5])
self.failIf(self.proto.timedOut)


def test_return(self):
"""
setTimeout should return the value of the previous timeout.
"""
self.proto.timeOut = 5

self.assertEqual(self.proto.setTimeout(10), 5)
self.assertEqual(self.proto.setTimeout(None), 10)
self.assertEqual(self.proto.setTimeout(1), None)
self.assertEqual(self.proto.timeOut, 1)

# Clean up the DelayedCall
self.proto.setTimeout(None)



class LimitTotalConnectionsFactoryTestCase(unittest.TestCase):
"""Tests for policies.LimitTotalConnectionsFactory"""
def testConnectionCounting(self):
# Make a basic factory
factory = policies.LimitTotalConnectionsFactory()
factory.protocol = protocol.Protocol

# connectionCount starts at zero
self.assertEqual(0, factory.connectionCount)

# connectionCount increments as connections are made
p1 = factory.buildProtocol(None)
self.assertEqual(1, factory.connectionCount)
p2 = factory.buildProtocol(None)
self.assertEqual(2, factory.connectionCount)

# and decrements as they are lost
p1.connectionLost(None)
self.assertEqual(1, factory.connectionCount)
p2.connectionLost(None)
self.assertEqual(0, factory.connectionCount)

def testConnectionLimiting(self):
# Make a basic factory with a connection limit of 1
factory = policies.LimitTotalConnectionsFactory()
factory.protocol = protocol.Protocol
factory.connectionLimit = 1

# Make a connection
p = factory.buildProtocol(None)
self.assertNotEqual(None, p)
self.assertEqual(1, factory.connectionCount)

# Try to make a second connection, which will exceed the connection
# limit. This should return None, because overflowProtocol is None.
self.assertEqual(None, factory.buildProtocol(None))
self.assertEqual(1, factory.connectionCount)

# Define an overflow protocol
class OverflowProtocol(protocol.Protocol):
def connectionMade(self):
factory.overflowed = True
factory.overflowProtocol = OverflowProtocol
factory.overflowed = False

# Try to make a second connection again, now that we have an overflow
# protocol. Note that overflow connections count towards the connection
# count.
op = factory.buildProtocol(None)
op.makeConnection(None) # to trigger connectionMade
self.assertEqual(True, factory.overflowed)
self.assertEqual(2, factory.connectionCount)

# Close the connections.
p.connectionLost(None)
self.assertEqual(1, factory.connectionCount)
op.connectionLost(None)
self.assertEqual(0, factory.connectionCount)


class WriteSequenceEchoProtocol(EchoProtocol):
def dataReceived(self, bytes):
if bytes.find(b'vector!') != -1:
self.transport.writeSequence([bytes])
else:
EchoProtocol.dataReceived(self, bytes)

class TestLoggingFactory(policies.TrafficLoggingFactory):
openFile = None
def open(self, name):
assert self.openFile is None, "open() called too many times"
self.openFile = NativeStringIO()
return self.openFile



class LoggingFactoryTestCase(unittest.TestCase):
"""
Tests for L{policies.TrafficLoggingFactory}.
"""

def test_thingsGetLogged(self):
"""
Check the output produced by L{policies.TrafficLoggingFactory}.
"""
wrappedFactory = Server()
wrappedFactory.protocol = WriteSequenceEchoProtocol
t = StringTransportWithDisconnection()
f = TestLoggingFactory(wrappedFactory, 'test')
p = f.buildProtocol(('1.2.3.4', 5678))
t.protocol = p
p.makeConnection(t)

v = f.openFile.getvalue()
self.assertIn('*', v)
self.failIf(t.value())

p.dataReceived(b'here are some bytes')

v = f.openFile.getvalue()
self.assertIn("C 1: %r" % (b'here are some bytes',), v)
self.assertIn("S 1: %r" % (b'here are some bytes',), v)
self.assertEqual(t.value(), b'here are some bytes')

t.clear()
p.dataReceived(b'prepare for vector! to the extreme')
v = f.openFile.getvalue()
self.assertIn("SV 1: %r" % ([b'prepare for vector! to the extreme'],), v)
self.assertEqual(t.value(), b'prepare for vector! to the extreme')

p.loseConnection()

v = f.openFile.getvalue()
self.assertIn('ConnectionDone', v)


def test_counter(self):
"""
Test counter management with the resetCounter method.
"""
wrappedFactory = Server()
f = TestLoggingFactory(wrappedFactory, 'test')
self.assertEqual(f._counter, 0)
f.buildProtocol(('1.2.3.4', 5678))
self.assertEqual(f._counter, 1)
# Reset log file
f.openFile = None
f.buildProtocol(('1.2.3.4', 5679))
self.assertEqual(f._counter, 2)

f.resetCounter()
self.assertEqual(f._counter, 0)