| #!/usr/bin/env python |
| """Support classes for automated testing. |
| |
| This module contains three parts: |
| |
| * `AsyncTestCase`/`AsyncHTTPTestCase`: Subclasses of unittest.TestCase |
| with additional support for testing asynchronous (IOLoop-based) code. |
| |
| * `LogTrapTestCase`: Subclass of unittest.TestCase that discards log output |
| from tests that pass and only produces output for failing tests. |
| |
| * `main()`: A simple test runner (wrapper around unittest.main()) with support |
| for the tornado.autoreload module to rerun the tests when code changes. |
| |
| These components may be used together or independently. In particular, |
| it is safe to combine AsyncTestCase and LogTrapTestCase via multiple |
| inheritance. See the docstrings for each class/function below for more |
| information. |
| """ |
| |
| from __future__ import absolute_import, division, with_statement |
| |
| from cStringIO import StringIO |
| try: |
| from tornado.httpclient import AsyncHTTPClient |
| from tornado.httpserver import HTTPServer |
| from tornado.ioloop import IOLoop |
| except ImportError: |
| # These modules are not importable on app engine. Parts of this module |
| # won't work, but e.g. LogTrapTestCase and main() will. |
| AsyncHTTPClient = None |
| HTTPServer = None |
| IOLoop = None |
| from tornado.stack_context import StackContext, NullContext |
| from tornado.util import raise_exc_info |
| import contextlib |
| import datetime |
| import logging |
| import signal |
| import sys |
| import unittest |
| |
| _next_port = 10000 |
| |
| |
| def get_unused_port(): |
| """Returns a (hopefully) unused port number.""" |
| global _next_port |
| port = _next_port |
| _next_port = _next_port + 1 |
| return port |
| |
| |
| class AsyncTestCase(unittest.TestCase): |
| """TestCase subclass for testing IOLoop-based asynchronous code. |
| |
| The unittest framework is synchronous, so the test must be complete |
| by the time the test method returns. This method provides the stop() |
| and wait() methods for this purpose. The test method itself must call |
| self.wait(), and asynchronous callbacks should call self.stop() to signal |
| completion. |
| |
| By default, a new IOLoop is constructed for each test and is available |
| as self.io_loop. This IOLoop should be used in the construction of |
| HTTP clients/servers, etc. If the code being tested requires a |
| global IOLoop, subclasses should override get_new_ioloop to return it. |
| |
| The IOLoop's start and stop methods should not be called directly. |
| Instead, use self.stop self.wait. Arguments passed to self.stop are |
| returned from self.wait. It is possible to have multiple |
| wait/stop cycles in the same test. |
| |
| Example:: |
| |
| # This test uses an asynchronous style similar to most async |
| # application code. |
| class MyTestCase(AsyncTestCase): |
| def test_http_fetch(self): |
| client = AsyncHTTPClient(self.io_loop) |
| client.fetch("http://www.tornadoweb.org/", self.handle_fetch) |
| self.wait() |
| |
| def handle_fetch(self, response): |
| # Test contents of response (failures and exceptions here |
| # will cause self.wait() to throw an exception and end the |
| # test). |
| # Exceptions thrown here are magically propagated to |
| # self.wait() in test_http_fetch() via stack_context. |
| self.assertIn("FriendFeed", response.body) |
| self.stop() |
| |
| # This test uses the argument passing between self.stop and self.wait |
| # for a simpler, more synchronous style. |
| # This style is recommended over the preceding example because it |
| # keeps the assertions in the test method itself, and is therefore |
| # less sensitive to the subtleties of stack_context. |
| class MyTestCase2(AsyncTestCase): |
| def test_http_fetch(self): |
| client = AsyncHTTPClient(self.io_loop) |
| client.fetch("http://www.tornadoweb.org/", self.stop) |
| response = self.wait() |
| # Test contents of response |
| self.assertIn("FriendFeed", response.body) |
| """ |
| def __init__(self, *args, **kwargs): |
| super(AsyncTestCase, self).__init__(*args, **kwargs) |
| self.__stopped = False |
| self.__running = False |
| self.__failure = None |
| self.__stop_args = None |
| self.__timeout = None |
| |
| def setUp(self): |
| super(AsyncTestCase, self).setUp() |
| self.io_loop = self.get_new_ioloop() |
| |
| def tearDown(self): |
| if (not IOLoop.initialized() or |
| self.io_loop is not IOLoop.instance()): |
| # Try to clean up any file descriptors left open in the ioloop. |
| # This avoids leaks, especially when tests are run repeatedly |
| # in the same process with autoreload (because curl does not |
| # set FD_CLOEXEC on its file descriptors) |
| self.io_loop.close(all_fds=True) |
| super(AsyncTestCase, self).tearDown() |
| |
| def get_new_ioloop(self): |
| '''Creates a new IOLoop for this test. May be overridden in |
| subclasses for tests that require a specific IOLoop (usually |
| the singleton). |
| ''' |
| return IOLoop() |
| |
| @contextlib.contextmanager |
| def _stack_context(self): |
| try: |
| yield |
| except Exception: |
| self.__failure = sys.exc_info() |
| self.stop() |
| |
| def __rethrow(self): |
| if self.__failure is not None: |
| failure = self.__failure |
| self.__failure = None |
| raise_exc_info(failure) |
| |
| def run(self, result=None): |
| with StackContext(self._stack_context): |
| super(AsyncTestCase, self).run(result) |
| # In case an exception escaped super.run or the StackContext caught |
| # an exception when there wasn't a wait() to re-raise it, do so here. |
| self.__rethrow() |
| |
| def stop(self, _arg=None, **kwargs): |
| '''Stops the ioloop, causing one pending (or future) call to wait() |
| to return. |
| |
| Keyword arguments or a single positional argument passed to stop() are |
| saved and will be returned by wait(). |
| ''' |
| assert _arg is None or not kwargs |
| self.__stop_args = kwargs or _arg |
| if self.__running: |
| self.io_loop.stop() |
| self.__running = False |
| self.__stopped = True |
| |
| def wait(self, condition=None, timeout=5): |
| """Runs the IOLoop until stop is called or timeout has passed. |
| |
| In the event of a timeout, an exception will be thrown. |
| |
| If condition is not None, the IOLoop will be restarted after stop() |
| until condition() returns true. |
| """ |
| if not self.__stopped: |
| if timeout: |
| def timeout_func(): |
| try: |
| raise self.failureException( |
| 'Async operation timed out after %s seconds' % |
| timeout) |
| except Exception: |
| self.__failure = sys.exc_info() |
| self.stop() |
| if self.__timeout is not None: |
| self.io_loop.remove_timeout(self.__timeout) |
| self.__timeout = self.io_loop.add_timeout(datetime.timedelta(seconds=timeout), timeout_func) |
| while True: |
| self.__running = True |
| with NullContext(): |
| # Wipe out the StackContext that was established in |
| # self.run() so that all callbacks executed inside the |
| # IOLoop will re-run it. |
| self.io_loop.start() |
| if (self.__failure is not None or |
| condition is None or condition()): |
| break |
| assert self.__stopped |
| self.__stopped = False |
| self.__rethrow() |
| result = self.__stop_args |
| self.__stop_args = None |
| return result |
| |
| |
| class AsyncHTTPTestCase(AsyncTestCase): |
| '''A test case that starts up an HTTP server. |
| |
| Subclasses must override get_app(), which returns the |
| tornado.web.Application (or other HTTPServer callback) to be tested. |
| Tests will typically use the provided self.http_client to fetch |
| URLs from this server. |
| |
| Example:: |
| |
| class MyHTTPTest(AsyncHTTPTestCase): |
| def get_app(self): |
| return Application([('/', MyHandler)...]) |
| |
| def test_homepage(self): |
| # The following two lines are equivalent to |
| # response = self.fetch('/') |
| # but are shown in full here to demonstrate explicit use |
| # of self.stop and self.wait. |
| self.http_client.fetch(self.get_url('/'), self.stop) |
| response = self.wait() |
| # test contents of response |
| ''' |
| def setUp(self): |
| super(AsyncHTTPTestCase, self).setUp() |
| self.__port = None |
| |
| self.http_client = AsyncHTTPClient(io_loop=self.io_loop) |
| self._app = self.get_app() |
| self.http_server = HTTPServer(self._app, io_loop=self.io_loop, |
| **self.get_httpserver_options()) |
| self.http_server.listen(self.get_http_port(), address="localhost") |
| |
| def get_app(self): |
| """Should be overridden by subclasses to return a |
| tornado.web.Application or other HTTPServer callback. |
| """ |
| raise NotImplementedError() |
| |
| def fetch(self, path, **kwargs): |
| """Convenience method to synchronously fetch a url. |
| |
| The given path will be appended to the local server's host and port. |
| Any additional kwargs will be passed directly to |
| AsyncHTTPClient.fetch (and so could be used to pass method="POST", |
| body="...", etc). |
| """ |
| self.http_client.fetch(self.get_url(path), self.stop, **kwargs) |
| return self.wait() |
| |
| def get_httpserver_options(self): |
| """May be overridden by subclasses to return additional |
| keyword arguments for HTTPServer. |
| """ |
| return {} |
| |
| def get_http_port(self): |
| """Returns the port used by the HTTPServer. |
| |
| A new port is chosen for each test. |
| """ |
| if self.__port is None: |
| self.__port = get_unused_port() |
| return self.__port |
| |
| def get_url(self, path): |
| """Returns an absolute url for the given path on the test server.""" |
| return 'http://localhost:%s%s' % (self.get_http_port(), path) |
| |
| def tearDown(self): |
| self.http_server.stop() |
| self.http_client.close() |
| super(AsyncHTTPTestCase, self).tearDown() |
| |
| |
| class LogTrapTestCase(unittest.TestCase): |
| """A test case that captures and discards all logging output |
| if the test passes. |
| |
| Some libraries can produce a lot of logging output even when |
| the test succeeds, so this class can be useful to minimize the noise. |
| Simply use it as a base class for your test case. It is safe to combine |
| with AsyncTestCase via multiple inheritance |
| ("class MyTestCase(AsyncHTTPTestCase, LogTrapTestCase):") |
| |
| This class assumes that only one log handler is configured and that |
| it is a StreamHandler. This is true for both logging.basicConfig |
| and the "pretty logging" configured by tornado.options. |
| """ |
| def run(self, result=None): |
| logger = logging.getLogger() |
| if len(logger.handlers) > 1: |
| # Multiple handlers have been defined. It gets messy to handle |
| # this, especially since the handlers may have different |
| # formatters. Just leave the logging alone in this case. |
| super(LogTrapTestCase, self).run(result) |
| return |
| if not logger.handlers: |
| logging.basicConfig() |
| self.assertEqual(len(logger.handlers), 1) |
| handler = logger.handlers[0] |
| assert isinstance(handler, logging.StreamHandler) |
| old_stream = handler.stream |
| try: |
| handler.stream = StringIO() |
| logging.info("RUNNING TEST: " + str(self)) |
| old_error_count = len(result.failures) + len(result.errors) |
| super(LogTrapTestCase, self).run(result) |
| new_error_count = len(result.failures) + len(result.errors) |
| if new_error_count != old_error_count: |
| old_stream.write(handler.stream.getvalue()) |
| finally: |
| handler.stream = old_stream |
| |
| |
| def main(): |
| """A simple test runner. |
| |
| This test runner is essentially equivalent to `unittest.main` from |
| the standard library, but adds support for tornado-style option |
| parsing and log formatting. |
| |
| The easiest way to run a test is via the command line:: |
| |
| python -m tornado.testing tornado.test.stack_context_test |
| |
| See the standard library unittest module for ways in which tests can |
| be specified. |
| |
| Projects with many tests may wish to define a test script like |
| tornado/test/runtests.py. This script should define a method all() |
| which returns a test suite and then call tornado.testing.main(). |
| Note that even when a test script is used, the all() test suite may |
| be overridden by naming a single test on the command line:: |
| |
| # Runs all tests |
| tornado/test/runtests.py |
| # Runs one test |
| tornado/test/runtests.py tornado.test.stack_context_test |
| |
| """ |
| from tornado.options import define, options, parse_command_line |
| |
| define('autoreload', type=bool, default=False, |
| help="DEPRECATED: use tornado.autoreload.main instead") |
| define('httpclient', type=str, default=None) |
| define('exception_on_interrupt', type=bool, default=True, |
| help=("If true (default), ctrl-c raises a KeyboardInterrupt " |
| "exception. This prints a stack trace but cannot interrupt " |
| "certain operations. If false, the process is more reliably " |
| "killed, but does not print a stack trace.")) |
| argv = [sys.argv[0]] + parse_command_line(sys.argv) |
| |
| if options.httpclient: |
| from tornado.httpclient import AsyncHTTPClient |
| AsyncHTTPClient.configure(options.httpclient) |
| |
| if not options.exception_on_interrupt: |
| signal.signal(signal.SIGINT, signal.SIG_DFL) |
| |
| if __name__ == '__main__' and len(argv) == 1: |
| print >> sys.stderr, "No tests specified" |
| sys.exit(1) |
| try: |
| # In order to be able to run tests by their fully-qualified name |
| # on the command line without importing all tests here, |
| # module must be set to None. Python 3.2's unittest.main ignores |
| # defaultTest if no module is given (it tries to do its own |
| # test discovery, which is incompatible with auto2to3), so don't |
| # set module if we're not asking for a specific test. |
| if len(argv) > 1: |
| unittest.main(module=None, argv=argv) |
| else: |
| unittest.main(defaultTest="all", argv=argv) |
| except SystemExit, e: |
| if e.code == 0: |
| logging.info('PASS') |
| else: |
| logging.error('FAIL') |
| if not options.autoreload: |
| raise |
| if options.autoreload: |
| import tornado.autoreload |
| tornado.autoreload.wait() |
| |
| if __name__ == '__main__': |
| main() |
