twisted.test.test_tcp_internals.SelectReactorTests

Tests for select-specific failure conditions.

Method	setUp	Undocumented
Method	tearDown	Undocumented
Method	port	Create, start, and return a new `Port`, also tracking it so it can be stopped in the test tear down.
Method	test_tooManyFilesFromAccept	`accept(2)` can fail with `EMFILE` when there are too many open file descriptors in the process. Test that this doesn't negatively impact any other existing connections.
Method	test_noBufferSpaceFromAccept	Similar to `test_tooManyFilesFromAccept`, but test the case where `accept(2)` fails with `ENOBUFS`.
Method	test_connectionAbortedFromAccept	Similar to `test_tooManyFilesFromAccept`, but test the case where `accept(2)` fails with `ECONNABORTED`.
Method	test_noFilesFromAccept	Similar to `test_tooManyFilesFromAccept`, but test the case where `accept(2)` fails with `ENFILE`.
Method	test_noMemoryFromAccept	Similar to `test_tooManyFilesFromAccept`, but test the case where `accept(2)` fails with `ENOMEM`.
Method	test_acceptScaling	No summary
Method	test_permissionFailure	`accept(2)` returning `EPERM` is treated as a transient failure and the call retried no more than the maximum number of consecutive `accept(2)` calls.
Method	test_unknownSocketErrorRaise	A `socket.error` raised by `accept(2)` whose `errno` is unknown to the recovery logic is logged.
Method	_acceptFailureTest	Test behavior in the face of an exception from `accept(2)`.

Inherited from TestCase:

Instance Variable	timeout	A real number of seconds. If set, the test will raise an error if it takes longer than `timeout` seconds. If not set, util.DEFAULT_TIMEOUT_DURATION is used.
Method	__init__	Construct an asynchronous test case for `methodName`.
Method	assertFailure	Fail if `deferred` does not errback with one of `expectedFailures`. Returns the original Deferred with callbacks added. You will need to return this Deferred from your test case.
Method	__call__	Run the test. Should always do exactly the same thing as run().
Method	deferSetUp	Undocumented
Method	deferTestMethod	Undocumented
Method	deferTearDown	Undocumented
Method	deferRunCleanups	Run any scheduled cleanups and report errors (if any to the result object.
Method	addCleanup	Extend the base cleanup feature with support for cleanup functions which return Deferreds.
Method	getSuppress	Undocumented
Method	getTimeout	No summary
Method	_run	Run a single method, either a test method or fixture.
Method	_ebDeferSetUp	Undocumented
Method	_cbDeferTestMethod	Undocumented
Method	_ebDeferTestMethod	Undocumented
Method	_ebDeferTearDown	Undocumented
Method	_cbDeferRunCleanups	Undocumented
Method	_cleanUp	Undocumented
Method	_classCleanUp	Undocumented
Method	_makeReactorMethod	Create a method which wraps the reactor method `name`. The new method issues a deprecation warning and calls the original.
Method	_deprecateReactor	Deprecate `iterate`, `crash` and `stop` on `reactor`. That is, each method is wrapped in a function that issues a deprecation warning, then calls the original.
Method	_undeprecateReactor	Restore the deprecated reactor methods. Undoes what `_deprecateReactor` did.
Method	_runCleanups	Run the cleanups added with `addCleanup` in order.
Method	_runFixturesAndTest	Really run `setUp`, the test method, and `tearDown`. Any of these may return `defer.Deferred`s. After they complete, do some reactor cleanup.
Method	_wait	Take a Deferred that only ever callbacks. Block until it happens.

Inherited from SynchronousTestCase (via TestCase):

Instance Variable	failureException	An exception class, defaulting to `FailTest`. If the test method raises this exception, it will be reported as a failure, rather than an exception. All of the assertion methods raise this if the assertion fails.
Instance Variable	skip	`None` or a string explaining why this test is to be skipped. If defined, the test will not be run. Instead, it will be reported to the result object as 'skipped' (if the `TestResult` supports skipping).
Instance Variable	todo	`None`, a string or a tuple of `(errors, reason)` where `errors` is either an exception class or an iterable of exception classes, and `reason` is a string. See `Todo` or `makeTodo` for more information.
Instance Variable	suppress	`None` or a list of tuples of `(args, kwargs)` to be passed to `warnings.filterwarnings`. Use these to suppress warnings raised in a test. Useful for testing deprecated code. See also `util.suppress`.
Method	__eq__	No summary
Method	__ne__	Undocumented
Method	__hash__	Undocumented
Method	shortDescription	Undocumented
Method	getSkip	No summary
Method	getTodo	No summary
Method	runTest	If no `methodName` argument is passed to the constructor, `run` will treat this method as the thing with the actual test inside.
Method	run	Run the test case, storing the results in `result`.
Method	patch	Monkey patch an object for the duration of the test.
Method	flushLoggedErrors	Remove stored errors received from the log.
Method	flushWarnings	Remove stored warnings from the list of captured warnings and return them.
Method	callDeprecated	Call a function that should have been deprecated at a specific version and in favor of a specific alternative, and assert that it was thusly deprecated.
Method	mktemp	Create a new path name which can be used for a new file or directory.
Method	_getSuppress	No summary
Method	_getSkipReason	Return the reason to use for skipping a test method.
Method	_installObserver	Undocumented
Method	_removeObserver	Undocumented

Inherited from _Assertions (via TestCase, SynchronousTestCase):

Method	fail	Absolutely fail the test. Do not pass go, do not collect $200.
Method	assertFalse	Fail the test if `condition` evaluates to True.
Method	assertTrue	Fail the test if `condition` evaluates to False.
Method	assertRaises	Fail the test unless calling the function `f` with the given `args` and `kwargs` raises `exception`. The failure will report the traceback and call stack of the unexpected exception.
Method	assertEqual	Fail the test if `first` and `second` are not equal.
Method	assertIs	Fail the test if `first` is not `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test.
Method	assertIsNot	Fail the test if `first` is `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test.
Method	assertNotEqual	Fail the test if `first` == `second`.
Method	assertIn	Fail the test if `containee` is not found in `container`.
Method	assertNotIn	Fail the test if `containee` is found in `container`.
Method	assertNotAlmostEqual	Fail if the two objects are equal as determined by their difference rounded to the given number of decimal places (default 7) and comparing to zero.
Method	assertAlmostEqual	Fail if the two objects are unequal as determined by their difference rounded to the given number of decimal places (default 7) and comparing to zero.
Method	assertApproximates	Fail if `first` - `second` > `tolerance`
Method	assertSubstring	Fail if `substring` does not exist within `astring`.
Method	assertNotSubstring	Fail if `astring` contains `substring`.
Method	assertWarns	Fail if the given function doesn't generate the specified warning when called. It calls the function, checks the warning, and forwards the result of the function if everything is fine.
Method	assertIsInstance	Fail if `instance` is not an instance of the given class or of one of the given classes.
Method	assertNotIsInstance	Fail if `instance` is an instance of the given class or of one of the given classes.
Method	successResultOf	Return the current success result of `deferred` or raise `self.failureException`.
Method	failureResultOf	Return the current failure result of `deferred` or raise `self.failureException`.
Method	assertNoResult	Assert that `deferred` does not have a result at this point.
Method	assertRegex	Fail the test if a `regexp` search of `text` fails.

def setUp(self):

Undocumented

def tearDown(self):

Undocumented

def port(self, portNumber, factory, interface):

Create, start, and return a new Port, also tracking it so it can be stopped in the test tear down.

def _acceptFailureTest(self, socketErrorNumber):

Test behavior in the face of an exception from accept(2).

On any exception which indicates the platform is unable or unwilling to allocate further resources to us, the existing port should remain listening, a message should be logged, and the exception should not propagate outward from doRead.

Parameters socketErrorNumber The errno to simulate from accept.

def test_tooManyFilesFromAccept(self):

accept(2) can fail with EMFILE when there are too many open file descriptors in the process. Test that this doesn't negatively impact any other existing connections.

EMFILE mainly occurs on Linux when the open file rlimit is encountered.

def test_noBufferSpaceFromAccept(self):

Similar to test_tooManyFilesFromAccept, but test the case where accept(2) fails with ENOBUFS.

This mainly occurs on Windows and FreeBSD, but may be possible on Linux and other platforms as well.

def test_connectionAbortedFromAccept(self):

Similar to test_tooManyFilesFromAccept, but test the case where accept(2) fails with ECONNABORTED.

It is not clear whether this is actually possible for TCP connections on modern versions of Linux.

def test_noFilesFromAccept(self):

Similar to test_tooManyFilesFromAccept, but test the case where accept(2) fails with ENFILE.

This can occur on Linux when the system has exhausted (!) its supply of inodes.

def test_noMemoryFromAccept(self):

Similar to test_tooManyFilesFromAccept, but test the case where accept(2) fails with ENOMEM.

On Linux at least, this can sensibly occur, even in a Python program (which eats memory like no ones business), when memory has become fragmented or low memory has been filled (d_alloc calls kmem_cache_alloc calls kmalloc - kmalloc only allocates out of low memory).

def test_acceptScaling(self):

tcp.Port.doRead increases the number of consecutive accept calls it performs if all of the previous accept calls succeed; otherwise, it reduces the number to the amount of successful calls.

def test_permissionFailure(self):

accept(2) returning EPERM is treated as a transient failure and the call retried no more than the maximum number of consecutive accept(2) calls.

def test_unknownSocketErrorRaise(self):

A socket.error raised by accept(2) whose errno is unknown to the recovery logic is logged.

API Documentation for twisted, generated by pydoctor at 2020-03-25 17:34:30.

twisted.test.test_tcp_internals.SelectReactorTests(TestCase) class documentation

`twisted.test.test_tcp_internals.SelectReactorTests(TestCase)` class documentation