def test_success(self):
"""
L{ThreadedResolver.getHostByName} returns a L{Deferred} which fires
with the value returned by the call to L{socket.gethostbyname} in the
threadpool of the reactor passed to L{ThreadedResolver.__init__}.
"""
ip = "10.0.0.17"
name = "foo.bar.example.com"
timeout = 30
reactor = FakeReactor()
self.addCleanup(reactor._stop)
lookedUp = []
resolvedTo = []
def fakeGetHostByName(name):
lookedUp.append(name)
return ip
self.patch(socket, 'gethostbyname', fakeGetHostByName)
resolver = ThreadedResolver(reactor)
d = resolver.getHostByName(name, (timeout, ))
d.addCallback(resolvedTo.append)
reactor._runThreadCalls()
self.assertEqual(lookedUp, [name])
self.assertEqual(resolvedTo, [ip])
# Make sure that any timeout-related stuff gets cleaned up.
reactor._clock.advance(timeout + 1)
self.assertEqual(reactor._clock.calls, [])
def test_failure(self):
"""
L{ThreadedResolver.getHostByName} returns a L{Deferred} which fires a
L{Failure} if the call to L{socket.gethostbyname} raises an exception.
"""
timeout = 30
reactor = FakeReactor()
self.addCleanup(reactor._stop)
def fakeGetHostByName(name):
raise IOError("ENOBUFS (this is a funny joke)")
self.patch(socket, 'gethostbyname', fakeGetHostByName)
failedWith = []
resolver = ThreadedResolver(reactor)
d = resolver.getHostByName("some.name", (timeout, ))
self.assertFailure(d, DNSLookupError)
d.addCallback(failedWith.append)
reactor._runThreadCalls()
self.assertEqual(len(failedWith), 1)
# Make sure that any timeout-related stuff gets cleaned up.
reactor._clock.advance(timeout + 1)
self.assertEqual(reactor._clock.calls, [])
def test_timeout(self):
"""
If L{socket.gethostbyname} does not complete before the specified
timeout elapsed, the L{Deferred} returned by
L{ThreadedResolver.getHostByName} fails with L{DNSLookupError}.
"""
timeout = 10
reactor = FakeReactor()
self.addCleanup(reactor._stop)
result = Queue()
def fakeGetHostByName(name):
raise result.get()
self.patch(socket, 'gethostbyname', fakeGetHostByName)
failedWith = []
resolver = ThreadedResolver(reactor)
d = resolver.getHostByName("some.name", (timeout, ))
self.assertFailure(d, DNSLookupError)
d.addCallback(failedWith.append)
reactor._clock.advance(timeout - 1)
self.assertEqual(failedWith, [])
reactor._clock.advance(1)
self.assertEqual(len(failedWith), 1)
# Eventually the socket.gethostbyname does finish - in this case, with
# an exception. Nobody cares, though.
result.put(IOError("The I/O was errorful"))
