summaryrefslogtreecommitdiffstats
path: root/Lib/test/test_timeout.py
blob: 3c75dcc6f922cc12b4dd58989355f272273d1749 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
"""Unit tests for socket timeout feature."""

import functools
import unittest
from test import support

# This requires the 'network' resource as given on the regrtest command line.
skip_expected = not support.is_resource_enabled('network')

import time
import errno
import socket


@functools.lru_cache()
def resolve_address(host, port):
    """Resolve an (host, port) to an address.

    We must perform name resolution before timeout tests, otherwise it will be
    performed by connect().
    """
    with support.transient_internet(host):
        return socket.getaddrinfo(host, port, socket.AF_INET,
                                  socket.SOCK_STREAM)[0][4]


class CreationTestCase(unittest.TestCase):
    """Test case for socket.gettimeout() and socket.settimeout()"""

    def setUp(self):
        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

    def tearDown(self):
        self.sock.close()

    def testObjectCreation(self):
        # Test Socket creation
        self.assertEqual(self.sock.gettimeout(), None,
                         "timeout not disabled by default")

    def testFloatReturnValue(self):
        # Test return value of gettimeout()
        self.sock.settimeout(7.345)
        self.assertEqual(self.sock.gettimeout(), 7.345)

        self.sock.settimeout(3)
        self.assertEqual(self.sock.gettimeout(), 3)

        self.sock.settimeout(None)
        self.assertEqual(self.sock.gettimeout(), None)

    def testReturnType(self):
        # Test return type of gettimeout()
        self.sock.settimeout(1)
        self.assertEqual(type(self.sock.gettimeout()), type(1.0))

        self.sock.settimeout(3.9)
        self.assertEqual(type(self.sock.gettimeout()), type(1.0))

    def testTypeCheck(self):
        # Test type checking by settimeout()
        self.sock.settimeout(0)
        self.sock.settimeout(0)
        self.sock.settimeout(0.0)
        self.sock.settimeout(None)
        self.assertRaises(TypeError, self.sock.settimeout, "")
        self.assertRaises(TypeError, self.sock.settimeout, "")
        self.assertRaises(TypeError, self.sock.settimeout, ())
        self.assertRaises(TypeError, self.sock.settimeout, [])
        self.assertRaises(TypeError, self.sock.settimeout, {})
        self.assertRaises(TypeError, self.sock.settimeout, 0j)

    def testRangeCheck(self):
        # Test range checking by settimeout()
        self.assertRaises(ValueError, self.sock.settimeout, -1)
        self.assertRaises(ValueError, self.sock.settimeout, -1)
        self.assertRaises(ValueError, self.sock.settimeout, -1.0)

    def testTimeoutThenBlocking(self):
        # Test settimeout() followed by setblocking()
        self.sock.settimeout(10)
        self.sock.setblocking(1)
        self.assertEqual(self.sock.gettimeout(), None)
        self.sock.setblocking(0)
        self.assertEqual(self.sock.gettimeout(), 0.0)

        self.sock.settimeout(10)
        self.sock.setblocking(0)
        self.assertEqual(self.sock.gettimeout(), 0.0)
        self.sock.setblocking(1)
        self.assertEqual(self.sock.gettimeout(), None)

    def testBlockingThenTimeout(self):
        # Test setblocking() followed by settimeout()
        self.sock.setblocking(0)
        self.sock.settimeout(1)
        self.assertEqual(self.sock.gettimeout(), 1)

        self.sock.setblocking(1)
        self.sock.settimeout(1)
        self.assertEqual(self.sock.gettimeout(), 1)


class TimeoutTestCase(unittest.TestCase):
    # There are a number of tests here trying to make sure that an operation
    # doesn't take too much longer than expected.  But competing machine
    # activity makes it inevitable that such tests will fail at times.
    # When fuzz was at 1.0, I (tim) routinely saw bogus failures on Win2K
    # and Win98SE.  Boosting it to 2.0 helped a lot, but isn't a real
    # solution.
    fuzz = 2.0

    localhost = support.HOST

    def setUp(self):
        raise NotImplementedError()

    tearDown = setUp

    def _sock_operation(self, count, timeout, method, *args):
        """
        Test the specified socket method.

        The method is run at most `count` times and must raise a socket.timeout
        within `timeout` + self.fuzz seconds.
        """
        self.sock.settimeout(timeout)
        method = getattr(self.sock, method)
        for i in range(count):
            t1 = time.time()
            try:
                method(*args)
            except socket.timeout as e:
                delta = time.time() - t1
                break
        else:
            self.fail('socket.timeout was not raised')
        # These checks should account for timing unprecision
        self.assertLess(delta, timeout + self.fuzz)
        self.assertGreater(delta, timeout - 1.0)


class TCPTimeoutTestCase(TimeoutTestCase):
    """TCP test case for socket.socket() timeout functions"""

    def setUp(self):
        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.addr_remote = resolve_address('www.python.org.', 80)

    def tearDown(self):
        self.sock.close()

    def testConnectTimeout(self):
        # Testing connect timeout is tricky: we need to have IP connectivity
        # to a host that silently drops our packets.  We can't simulate this
        # from Python because it's a function of the underlying TCP/IP stack.
        # So, the following Snakebite host has been defined:
        blackhole = resolve_address('blackhole.snakebite.net', 56666)

        # Blackhole has been configured to silently drop any incoming packets.
        # No RSTs (for TCP) or ICMP UNREACH (for UDP/ICMP) will be sent back
        # to hosts that attempt to connect to this address: which is exactly
        # what we need to confidently test connect timeout.

        # However, we want to prevent false positives.  It's not unreasonable
        # to expect certain hosts may not be able to reach the blackhole, due
        # to firewalling or general network configuration.  In order to improve
        # our confidence in testing the blackhole, a corresponding 'whitehole'
        # has also been set up using one port higher:
        whitehole = resolve_address('whitehole.snakebite.net', 56667)

        # This address has been configured to immediately drop any incoming
        # packets as well, but it does it respectfully with regards to the
        # incoming protocol.  RSTs are sent for TCP packets, and ICMP UNREACH
        # is sent for UDP/ICMP packets.  This means our attempts to connect to
        # it should be met immediately with ECONNREFUSED.  The test case has
        # been structured around this premise: if we get an ECONNREFUSED from
        # the whitehole, we proceed with testing connect timeout against the
        # blackhole.  If we don't, we skip the test (with a message about not
        # getting the required RST from the whitehole within the required
        # timeframe).

        # For the records, the whitehole/blackhole configuration has been set
        # up using the 'pf' firewall (available on BSDs), using the following:
        #
        #   ext_if="bge0"
        #
        #   blackhole_ip="35.8.247.6"
        #   whitehole_ip="35.8.247.6"
        #   blackhole_port="56666"
        #   whitehole_port="56667"
        #
        #   block return in log quick on $ext_if proto { tcp udp } \
        #       from any to $whitehole_ip port $whitehole_port
        #   block drop in log quick on $ext_if proto { tcp udp } \
        #       from any to $blackhole_ip port $blackhole_port
        #

        skip = True
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        # Use a timeout of 3 seconds.  Why 3?  Because it's more than 1, and
        # less than 5.  i.e. no particular reason.  Feel free to tweak it if
        # you feel a different value would be more appropriate.
        timeout = 3
        sock.settimeout(timeout)
        try:
            sock.connect((whitehole))
        except socket.timeout:
            pass
        except OSError as err:
            if err.errno == errno.ECONNREFUSED:
                skip = False
        finally:
            sock.close()
            del sock

        if skip:
            self.skipTest(
                "We didn't receive a connection reset (RST) packet from "
                "{}:{} within {} seconds, so we're unable to test connect "
                "timeout against the corresponding {}:{} (which is "
                "configured to silently drop packets)."
                    .format(
                        whitehole[0],
                        whitehole[1],
                        timeout,
                        blackhole[0],
                        blackhole[1],
                    )
            )

        # All that hard work just to test if connect times out in 0.001s ;-)
        self.addr_remote = blackhole
        with support.transient_internet(self.addr_remote[0]):
            self._sock_operation(1, 0.001, 'connect', self.addr_remote)

    def testRecvTimeout(self):
        # Test recv() timeout
        with support.transient_internet(self.addr_remote[0]):
            self.sock.connect(self.addr_remote)
            self._sock_operation(1, 1.5, 'recv', 1024)

    def testAcceptTimeout(self):
        # Test accept() timeout
        support.bind_port(self.sock, self.localhost)
        self.sock.listen()
        self._sock_operation(1, 1.5, 'accept')

    def testSend(self):
        # Test send() timeout
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as serv:
            support.bind_port(serv, self.localhost)
            serv.listen()
            self.sock.connect(serv.getsockname())
            # Send a lot of data in order to bypass buffering in the TCP stack.
            self._sock_operation(100, 1.5, 'send', b"X" * 200000)

    def testSendto(self):
        # Test sendto() timeout
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as serv:
            support.bind_port(serv, self.localhost)
            serv.listen()
            self.sock.connect(serv.getsockname())
            # The address argument is ignored since we already connected.
            self._sock_operation(100, 1.5, 'sendto', b"X" * 200000,
                                 serv.getsockname())

    def testSendall(self):
        # Test sendall() timeout
        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as serv:
            support.bind_port(serv, self.localhost)
            serv.listen()
            self.sock.connect(serv.getsockname())
            # Send a lot of data in order to bypass buffering in the TCP stack.
            self._sock_operation(100, 1.5, 'sendall', b"X" * 200000)


class UDPTimeoutTestCase(TimeoutTestCase):
    """UDP test case for socket.socket() timeout functions"""

    def setUp(self):
        self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

    def tearDown(self):
        self.sock.close()

    def testRecvfromTimeout(self):
        # Test recvfrom() timeout
        # Prevent "Address already in use" socket exceptions
        support.bind_port(self.sock, self.localhost)
        self._sock_operation(1, 1.5, 'recvfrom', 1024)


def test_main():
    support.requires('network')
    support.run_unittest(
        CreationTestCase,
        TCPTimeoutTestCase,
        UDPTimeoutTestCase,
    )

if __name__ == "__main__":
    test_main()