def get_page(self):
self.application.http_client_factory.register_upstream(
'retry_non_idempotent_503', {'retry_policy': 'non_idempotent_503'},
[get_server(self, 'broken'),
get_server(self, 'normal')])
self.application.http_client_factory.register_upstream(
'do_not_retry_non_idempotent_503', {},
[get_server(self, 'broken'),
get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'retry_non_idempotent_503')
check_all_requests_done(self, 'do_not_retry_non_idempotent_503')
async_group = AsyncGroup(check_requests_cb)
def callback_post_without_retry(_, response):
if response.code != 503:
raise HTTPError(500)
def callback_post_with_retry(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = text
self.post_url('retry_non_idempotent_503',
self.request.path,
callback=async_group.add(callback_post_with_retry))
self.post_url('do_not_retry_non_idempotent_503',
self.request.path,
callback=async_group.add(callback_post_without_retry))
def get_page(self):
n = int(self.get_argument('n'))
self.add_header('Content-Type', media_types.TEXT_PLAIN)
if n < 2:
self.text = '1'
return
self.acc = 0
def intermediate_cb(text, response):
self.acc += int(text)
def final_cb():
self.text = str(self.acc)
grp = AsyncGroup(final_cb, name='acc')
self.get_url(self.request.host,
self.request.path,
data={'n': str(n - 1)},
callback=grp.add(intermediate_cb))
self.get_url(self.request.host,
self.request.path,
data={'n': str(n - 2)},
callback=grp.add(intermediate_cb))
def get_page(self):
self.application.http_client_factory.register_upstream(
'retry_connect', {},
[get_server(self, 'free'),
get_server(self, 'normal')])
self.text = ''
def check_requests_cb():
check_all_requests_done(self, 'retry_connect')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = self.text + text
self.post_url('retry_connect',
self.request.path,
callback=async_group.add(callback_post))
self.post_url('retry_connect',
self.request.path,
callback=async_group.add(callback_post))
self.post_url('retry_connect',
self.request.path,
callback=async_group.add(callback_post))
check_all_servers_occupied(self, 'retry_connect')
def test_callbacks(self):
data = []
def callback2():
data.append(2)
def finish_callback():
self.assertEqual(data, [1, 2])
data.append(3)
ag = AsyncGroup(finish_callback)
cb1 = ag.add(partial(data.append, 1))
cb2 = ag.add(callback2)
self.assertEqual(ag._finished, False)
ag.try_finish()
self.assertEqual(ag._finished, False)
cb1()
self.assertEqual(ag._finished, False)
cb2()
self.assertEqual(ag._finished, True)
self.assertEqual(data, [1, 2, 3])
def group(self, futures, callback=None, name=None):
group_future = Future()
results_holder = {}
def group_callback():
if callable(callback):
callback(results_holder)
group_future.set_result(results_holder)
def future_callback(name, future):
results_holder[name] = future.result()
async_group = AsyncGroup(self.finish_group.add(
self.check_finished(group_callback)),
name=name)
for name, future in futures.items():
if future.done():
future_callback(name, future)
else:
self.add_future(
future, async_group.add(partial(future_callback, name)))
async_group.try_finish_async()
return group_future
def get_page(self):
self.application.http_client_factory.register_upstream('retry_non_idempotent_503',
{'retry_policy': 'non_idempotent_503'},
[get_server(self, 'broken'), get_server(self, 'normal')])
self.application.http_client_factory.register_upstream('do_not_retry_non_idempotent_503', {},
[get_server(self, 'broken'), get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'retry_non_idempotent_503')
check_all_requests_done(self, 'do_not_retry_non_idempotent_503')
async_group = AsyncGroup(check_requests_cb)
def callback_post_without_retry(_, response):
if response.code != 503:
raise HTTPError(500)
def callback_post_with_retry(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = text
self.post_url('retry_non_idempotent_503', self.request.path,
callback=async_group.add(callback_post_with_retry))
self.post_url('do_not_retry_non_idempotent_503', self.request.path,
callback=async_group.add(callback_post_without_retry))
def test_finish(self):
f = Future()
ag = AsyncGroup(partial(f.set_result, True))
self.assertEqual(ag._finished, False)
ag.add_notification()
ag.finish()
self.assertEqual(ag._finished, True)
self.assertEqual(f.result(), True)
def test_exception_in_last(self):
def callback2():
raise Exception('callback1 error')
def finish_callback():
self.fail('finish_callback should not be called')
ag = AsyncGroup(finish_callback, name='test_group')
cb1 = ag.add(lambda: None)
cb2 = ag.add(callback2)
cb1()
with ExpectLog(async_logger, r'.*aborting AsyncGroup\(name=test_group, finished=False\)'):
self.assertRaises(Exception, cb2)
self.assertEqual(ag._finished, True)
def get_page(self):
self.application.http_client_factory.register_upstream('no_retry_error', {},
[get_server(self, 'broken'), get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'no_retry_error')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error and response.code == 500:
self.text = 'no retry error'
return
self.text = text
self.post_url('no_retry_error', self.request.path, callback=async_group.add(callback_post))
def test_exception_in_final(self):
def finish_callback():
raise Exception('callback1 error')
ag = AsyncGroup(finish_callback)
self.assertRaises(Exception, ag.try_finish)
self.assertEqual(ag._finished, True)
def get_page(self):
self.application.http_client_factory.register_upstream('retry_on_timeout', {},
[get_server(self, 'broken'), get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'retry_on_timeout')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = text
self.delete_url('retry_on_timeout', self.request.path, callback=async_group.add(callback_post),
connect_timeout=0.1, request_timeout=0.3, max_timeout_tries=2)
def prepare(self):
self.active_limit = frontik.handler_active_limit.ActiveHandlersLimit(self.statsd_client)
self.debug_mode = DebugMode(self)
self.finish_group = AsyncGroup(lambda: None, name='finish')
self.json_producer = self.application.json.get_producer(self)
self.json = self.json_producer.json
self.xml_producer = self.application.xml.get_producer(self)
self.doc = self.xml_producer.doc
self._http_client = self.application.http_client_factory.get_http_client(
self.modify_http_client_request, self.debug_mode.enabled
) # type: HttpClient
self._handler_finished_notification = self.finish_group.add_notification()
super().prepare()
def test_exception_in_last(self):
def callback2():
raise Exception('callback1 error')
def finish_callback():
self.fail('finish_callback should not be called')
ag = AsyncGroup(finish_callback, name='test_group')
cb1 = ag.add(lambda: None)
cb2 = ag.add(callback2)
cb1()
with ExpectLog(
async_logger,
r'.*aborting AsyncGroup\(name=test_group, finished=False\)'):
self.assertRaises(Exception, cb2)
self.assertEqual(ag._finished, True)
def test_notifications(self):
f = Future()
ag = AsyncGroup(partial(f.set_result, True))
not1 = ag.add_notification()
not2 = ag.add_notification()
self.assertEqual(ag._finished, False)
not1()
self.assertEqual(ag._finished, False)
not2('params', are='ignored')
self.assertEqual(ag._finished, True)
self.assertEqual(f.result(), True)
with ExpectLog(async_logger, r'.*trying to finish already finished AsyncGroup\(name=None, finished=True\)'):
ag.finish()
def get_page(self):
self.application.http_client_factory.register_upstream('retry_connect', {},
[get_server(self, 'free'), get_server(self, 'normal')])
self.text = ''
def check_requests_cb():
check_all_requests_done(self, 'retry_connect')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = self.text + text
self.post_url('retry_connect', self.request.path, callback=async_group.add(callback_post))
self.post_url('retry_connect', self.request.path, callback=async_group.add(callback_post))
self.post_url('retry_connect', self.request.path, callback=async_group.add(callback_post))
check_all_servers_occupied(self, 'retry_connect')
def test_exception_in_first(self):
def callback1():
raise Exception('callback1 error')
def callback2():
self.fail('callback2 should not be called')
def finish_callback():
self.fail('finish_callback should not be called')
ag = AsyncGroup(finish_callback, name='test_group')
cb1 = ag.add(callback1)
cb2 = ag.add(callback2)
self.assertRaises(Exception, cb1)
self.assertEqual(ag._finished, True)
with ExpectLog(async_logger, r'.*ignoring executing callback in AsyncGroup\(name=test_group, finished=True\)'):
cb2()
self.assertEqual(ag._finished, True)
def get_page(self):
self.application.http_client_factory.register_upstream(
'no_retry_error', {},
[get_server(self, 'broken'),
get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'no_retry_error')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error and response.code == 500:
self.text = 'no retry error'
return
self.text = text
self.post_url('no_retry_error',
self.request.path,
callback=async_group.add(callback_post))
def test_callbacks(self):
data = []
def callback2():
data.append(2)
def finish_callback():
self.assertEqual(data, [1, 2])
data.append(3)
ag = AsyncGroup(finish_callback)
cb1 = ag.add(partial(data.append, 1))
cb2 = ag.add(callback2)
self.assertEqual(ag._finished, False)
ag.try_finish()
self.assertEqual(ag._finished, False)
cb1()
self.assertEqual(ag._finished, False)
cb2()
self.assertEqual(ag._finished, True)
self.assertEqual(data, [1, 2, 3])
def test_notifications(self):
f = Future()
ag = AsyncGroup(partial(f.set_result, True))
not1 = ag.add_notification()
not2 = ag.add_notification()
self.assertEqual(ag._finished, False)
not1()
self.assertEqual(ag._finished, False)
not2('params', are='ignored')
self.assertEqual(ag._finished, True)
self.assertEqual(f.result(), True)
with ExpectLog(
async_logger,
r'.*trying to finish already finished AsyncGroup\(name=None, finished=True\)'
):
ag.finish()
def get_page(self):
server = get_server(self, 'normal')
self.application.http_client_factory.register_upstream(
'no_available_backend', {}, [server])
server.is_active = False
def check_requests_cb():
check_all_requests_done(self, 'no_available_backend')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error and response.code == 502:
self.text = 'no backend available'
return
self.text = text
self.post_url('no_available_backend',
self.request.path,
callback=async_group.add(callback_post))
check_all_requests_done(self, 'no_available_backend')
def get_page(self):
self.application.http_client_factory.register_upstream(
'retry_on_timeout', {},
[get_server(self, 'broken'),
get_server(self, 'normal')])
def check_requests_cb():
check_all_requests_done(self, 'retry_on_timeout')
async_group = AsyncGroup(check_requests_cb)
def callback_post(text, response):
if response.error or text is None:
raise HTTPError(500)
self.text = text
self.delete_url('retry_on_timeout',
self.request.path,
callback=async_group.add(callback_post),
connect_timeout=0.1,
request_timeout=0.3,
max_timeout_tries=2)
def test_exception_in_first(self):
def callback1():
raise Exception('callback1 error')
def callback2():
self.fail('callback2 should not be called')
def finish_callback():
self.fail('finish_callback should not be called')
ag = AsyncGroup(finish_callback, name='test_group')
cb1 = ag.add(callback1)
cb2 = ag.add(callback2)
self.assertRaises(Exception, cb1)
self.assertEqual(ag._finished, True)
with ExpectLog(
async_logger,
r'.*ignoring executing callback in AsyncGroup\(name=test_group, finished=True\)'
):
cb2()
self.assertEqual(ag._finished, True)
def test_finish(self):
f = Future()
ag = AsyncGroup(partial(f.set_result, True))
self.assertEqual(ag._finished, False)
ag.add_notification()
ag.finish()
self.assertEqual(ag._finished, True)
self.assertEqual(f.result(), True)
def prepare(self):
self._http_client = self.application.http_client_factory.get_http_client(
self, self.modify_http_client_request
) # type: HttpClient
self.active_limit = frontik.handler_active_limit.ActiveHandlersLimit(self.statsd_client)
self.debug_mode = DebugMode(self)
self.finish_group = AsyncGroup(lambda: None, name='finish')
self._handler_finished_notification = self.finish_group.add_notification()
self.json_producer = self.application.json.get_producer(self)
self.json = self.json_producer.json
self.xml_producer = self.application.xml.get_producer(self)
self.doc = self.xml_producer.doc
super().prepare()
def get_page(self):
n = int(self.get_argument('n'))
self.add_header('Content-Type', media_types.TEXT_PLAIN)
if n < 2:
self.text = '1'
return
self.acc = 0
def intermediate_cb(text, response):
self.acc += int(text)
def final_cb():
self.text = str(self.acc)
grp = AsyncGroup(final_cb, name='acc')
self.get_url(self.request.host, self.request.path, data={'n': str(n - 1)}, callback=grp.add(intermediate_cb))
self.get_url(self.request.host, self.request.path, data={'n': str(n - 2)}, callback=grp.add(intermediate_cb))
class PageHandler(RequestHandler):
preprocessors = ()
def __init__(self, application, request, **kwargs):
self.name = self.__class__.__name__
self.request_id = request.request_id = request_context.get_request_id()
self.config = application.config
self.log = handler_logger
self.text = None
super().__init__(application, request, **kwargs)
self._preprocessor_futures = []
self._exception_hooks = []
for integration in application.available_integrations:
integration.initialize_handler(self)
self.stages_logger = StagesLogger(request, self.statsd_client)
self._debug_access = None
self._render_postprocessors = []
self._postprocessors = []
def __repr__(self):
return '.'.join([self.__module__, self.__class__.__name__])
def prepare(self):
self._http_client = self.application.http_client_factory.get_http_client(
self, self.modify_http_client_request
) # type: HttpClient
self.active_limit = frontik.handler_active_limit.ActiveHandlersLimit(self.statsd_client)
self.debug_mode = DebugMode(self)
self.finish_group = AsyncGroup(lambda: None, name='finish')
self._handler_finished_notification = self.finish_group.add_notification()
self.json_producer = self.application.json.get_producer(self)
self.json = self.json_producer.json
self.xml_producer = self.application.xml.get_producer(self)
self.doc = self.xml_producer.doc
super().prepare()
def require_debug_access(self, login=None, passwd=None):
if self._debug_access is None:
if options.debug:
debug_access = True
else:
check_login = login if login is not None else options.debug_login
check_passwd = passwd if passwd is not None else options.debug_password
frontik.auth.check_debug_auth(self, check_login, check_passwd)
debug_access = True
self._debug_access = debug_access
def set_default_headers(self):
self._headers = tornado.httputil.HTTPHeaders({
'Server': f'Frontik/{frontik_version}',
'X-Request-Id': self.request_id,
})
def decode_argument(self, value, name=None):
try:
return super().decode_argument(value, name)
except (UnicodeError, tornado.web.HTTPError):
self.log.warning('cannot decode utf-8 query parameter, trying other charsets')
try:
return frontik.util.decode_string_from_charset(value)
except UnicodeError:
self.log.exception('cannot decode argument, ignoring invalid chars')
return value.decode('utf-8', 'ignore')
def set_status(self, status_code, reason=None):
status_code = _fallback_status_code(status_code)
super().set_status(status_code, reason=reason)
def redirect(self, url, *args, **kwargs):
self.log.info('redirecting to: %s', url)
return super().redirect(url, *args, **kwargs)
def reverse_url(self, name, *args, **kwargs):
return self.application.reverse_url(name, *args, **kwargs)
@classmethod
def add_callback(cls, callback, *args, **kwargs):
IOLoop.current().add_callback(callback, *args, **kwargs)
@classmethod
def add_timeout(cls, deadline, callback, *args, **kwargs):
return IOLoop.current().add_timeout(deadline, callback, *args, **kwargs)
@staticmethod
def remove_timeout(timeout):
IOLoop.current().remove_timeout(timeout)
@classmethod
def add_future(cls, future, callback):
IOLoop.current().add_future(future, callback)
# Requests handling
def _execute(self, transforms, *args, **kwargs):
request_context.set_handler_name(repr(self))
with stack_context.ExceptionStackContext(self._stack_context_handle_exception):
return super()._execute(transforms, *args, **kwargs)
@gen.coroutine
def get(self, *args, **kwargs):
yield self._execute_page(self.get_page)
@gen.coroutine
def post(self, *args, **kwargs):
yield self._execute_page(self.post_page)
@gen.coroutine
def head(self, *args, **kwargs):
yield self._execute_page(self.get_page)
@gen.coroutine
def delete(self, *args, **kwargs):
yield self._execute_page(self.delete_page)
@gen.coroutine
def put(self, *args, **kwargs):
yield self._execute_page(self.put_page)
def options(self, *args, **kwargs):
self.__return_405()
@gen.coroutine
def _execute_page(self, page_handler_method):
self.stages_logger.commit_stage('prepare')
preprocessors = _unwrap_preprocessors(self.preprocessors) + _get_preprocessors(page_handler_method.__func__)
preprocessors_completed = yield self._run_preprocessors(preprocessors)
if not preprocessors_completed:
self.log.info('page was already finished, skipping page method')
return
yield gen.coroutine(page_handler_method)()
self._handler_finished_notification()
yield self.finish_group.get_finish_future()
render_result = yield self._postprocess()
if render_result is not None:
self.write(render_result)
def get_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def post_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def put_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def delete_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def __return_405(self):
allowed_methods = [
name for name in ('get', 'post', 'put', 'delete') if f'{name}_page' in vars(self.__class__)
]
self.set_header('Allow', ', '.join(allowed_methods))
self.set_status(405)
self.finish()
def get_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def post_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def put_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def delete_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def __return_error(self, response_code):
self.send_error(response_code if 300 <= response_code < 500 else 502)
# Finish page
def is_finished(self):
return self._finished
def check_finished(self, callback):
@wraps(callback)
def wrapper(*args, **kwargs):
if self._finished:
self.log.warning('page was already finished, %s ignored', callback)
else:
return callback(*args, **kwargs)
return wrapper
def finish_with_postprocessors(self):
if not self.finish_group.get_finish_future().done():
self.finish_group.abort()
def _cb(future):
if future.result() is not None:
self.finish(future.result())
self.add_future(self._postprocess(), _cb)
@gen.coroutine
def _postprocess(self):
if self._finished:
self.log.info('page was already finished, skipping postprocessors')
return
postprocessors_completed = yield self._run_postprocessors(self._postprocessors)
self.stages_logger.commit_stage('page')
if not postprocessors_completed:
self.log.info('page was already finished, skipping page producer')
return
if self.text is not None:
renderer = self._generic_producer
elif not self.json.is_empty():
renderer = self.json_producer
else:
renderer = self.xml_producer
self.log.debug('using %s renderer', renderer)
rendered_result = yield renderer()
postprocessed_result = yield self._run_template_postprocessors(self._render_postprocessors, rendered_result)
return postprocessed_result
def on_connection_close(self):
self.finish_group.abort()
self.stages_logger.commit_stage('page')
self.stages_logger.flush_stages(408)
self.cleanup()
def on_finish(self):
self.stages_logger.commit_stage('flush')
self.stages_logger.flush_stages(self.get_status())
def register_exception_hook(self, exception_hook):
"""
Adds a function to the list of hooks, which are executed when `log_exception` is called.
`exception_hook` must have the same signature as `log_exception`
"""
self._exception_hooks.append(exception_hook)
def log_exception(self, typ, value, tb):
super().log_exception(typ, value, tb)
for exception_hook in self._exception_hooks:
exception_hook(typ, value, tb)
def _handle_request_exception(self, e):
if isinstance(e, AbortAsyncGroup):
self.log.info('page was aborted, skipping postprocessing')
elif isinstance(e, FinishWithPostprocessors):
if e.wait_finish_group:
self._handler_finished_notification()
self.add_future(self.finish_group.get_finish_future(), lambda _: self.finish_with_postprocessors())
else:
self.finish_with_postprocessors()
elif isinstance(e, FailFastError):
response = e.failed_request.response
request = e.failed_request.request
if self.log.isEnabledFor(logging.WARNING):
_max_uri_length = 24
request_name = request.get_host() + request.uri[:_max_uri_length]
if len(request.uri) > _max_uri_length:
request_name += '...'
if request.name:
request_name = f'{request_name} ({request.name})'
self.log.warning('FailFastError: request %s failed with %s code', request_name, response.code)
try:
error_method_name = f'{self.request.method.lower()}_page_fail_fast'
method = getattr(self, error_method_name, None)
if callable(method):
method(e.failed_request)
else:
self.__return_error(e.failed_request.response.code)
except Exception as exc:
super()._handle_request_exception(exc)
else:
super()._handle_request_exception(e)
def send_error(self, status_code=500, **kwargs):
"""`send_error` is adapted to support `write_error` that can call
`finish` asynchronously.
"""
self.stages_logger.commit_stage('page')
if self._headers_written:
super().send_error(status_code, **kwargs)
return
reason = kwargs.get('reason')
if 'exc_info' in kwargs:
exception = kwargs['exc_info'][1]
if isinstance(exception, tornado.web.HTTPError) and exception.reason:
reason = exception.reason
else:
exception = None
if not isinstance(exception, HTTPErrorWithPostprocessors):
self.clear()
self.set_status(status_code, reason=reason)
try:
self.write_error(status_code, **kwargs)
except Exception:
self.log.exception('Uncaught exception in write_error')
if not self._finished:
self.finish()
def write_error(self, status_code=500, **kwargs):
"""
`write_error` can call `finish` asynchronously if HTTPErrorWithPostprocessors is raised.
"""
if 'exc_info' in kwargs:
exception = kwargs['exc_info'][1]
else:
exception = None
if isinstance(exception, HTTPErrorWithPostprocessors):
self.finish_with_postprocessors()
return
self.set_header('Content-Type', media_types.TEXT_HTML)
return super().write_error(status_code, **kwargs)
def cleanup(self):
if hasattr(self, 'active_limit'):
self.active_limit.release()
def finish(self, chunk=None):
self.stages_logger.commit_stage('postprocess')
if self._status_code in (204, 304) or (100 <= self._status_code < 200):
self._write_buffer = []
chunk = None
super().finish(chunk)
self.cleanup()
# Preprocessors and postprocessors
def add_preprocessor_future(self, future):
if self._preprocessor_futures is None:
raise Exception(
'preprocessors chain is already finished, calling add_preprocessor_future at this time is incorrect'
)
self._preprocessor_futures.append(future)
return future
@gen.coroutine
def _run_preprocessors(self, preprocessors):
for p in preprocessors:
yield gen.coroutine(p)(self)
if self._finished:
self.log.info('page was already finished, breaking preprocessors chain')
return False
yield gen.multi(self._preprocessor_futures)
self._preprocessor_futures = None
if self._finished:
self.log.info('page was already finished, breaking preprocessors chain')
return False
return True
@gen.coroutine
def _run_postprocessors(self, postprocessors):
for p in postprocessors:
yield gen.coroutine(p)(self)
if self._finished:
self.log.warning('page was already finished, breaking postprocessors chain')
return False
return True
@gen.coroutine
def _run_template_postprocessors(self, postprocessors, rendered_template):
for p in postprocessors:
rendered_template = yield gen.coroutine(p)(self, rendered_template)
if self._finished:
self.log.warning('page was already finished, breaking postprocessors chain')
return None
return rendered_template
def add_render_postprocessor(self, postprocessor):
self._render_postprocessors.append(postprocessor)
def add_postprocessor(self, postprocessor):
self._postprocessors.append(postprocessor)
# Producers
async def _generic_producer(self):
self.log.debug('finishing plaintext')
if self._headers.get('Content-Type') is None:
self.set_header('Content-Type', media_types.TEXT_HTML)
return self.text
def xml_from_file(self, filename):
return self.xml_producer.xml_from_file(filename)
def set_xsl(self, filename):
return self.xml_producer.set_xsl(filename)
def set_template(self, filename):
return self.json_producer.set_template(filename)
# HTTP client methods
def modify_http_client_request(self, balanced_request):
pass
def group(self, futures, callback=None, name=None):
return self._http_client.group(futures, callback, name)
def get_url(self, host, uri, *, name=None, data=None, headers=None, follow_redirects=True,
connect_timeout=None, request_timeout=None, max_timeout_tries=None,
callback=None, add_to_finish_group=True, parse_response=True, parse_on_error=True, fail_fast=False):
return self._http_client.get_url(
host, uri, name=name, data=data, headers=headers, follow_redirects=follow_redirects,
connect_timeout=connect_timeout, request_timeout=request_timeout, max_timeout_tries=max_timeout_tries,
callback=callback, add_to_finish_group=add_to_finish_group, parse_response=parse_response,
parse_on_error=parse_on_error, fail_fast=fail_fast
)
def head_url(self, host, uri, *, name=None, data=None, headers=None, follow_redirects=True,
connect_timeout=None, request_timeout=None, max_timeout_tries=None,
callback=None, add_to_finish_group=True, fail_fast=False):
return self._http_client.head_url(
host, uri, data=data, name=name, headers=headers, follow_redirects=follow_redirects,
connect_timeout=connect_timeout, request_timeout=request_timeout, max_timeout_tries=max_timeout_tries,
callback=callback, add_to_finish_group=add_to_finish_group, fail_fast=fail_fast
)
def post_url(self, host, uri, *,
name=None, data='', headers=None, files=None, content_type=None, follow_redirects=True,
connect_timeout=None, request_timeout=None, max_timeout_tries=None, idempotent=False,
callback=None, add_to_finish_group=True, parse_response=True, parse_on_error=True,
fail_fast=False):
return self._http_client.post_url(
host, uri, data=data, name=name, headers=headers, files=files, content_type=content_type,
follow_redirects=follow_redirects, connect_timeout=connect_timeout, request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries, idempotent=idempotent, callback=callback,
add_to_finish_group=add_to_finish_group, parse_response=parse_response, parse_on_error=parse_on_error,
fail_fast=fail_fast
)
def put_url(self, host, uri, *, name=None, data='', headers=None, content_type=None,
connect_timeout=None, request_timeout=None, max_timeout_tries=None,
callback=None, add_to_finish_group=True, parse_response=True, parse_on_error=True, fail_fast=False):
return self._http_client.put_url(
host, uri, name=name, data=data, headers=headers, content_type=content_type,
connect_timeout=connect_timeout, request_timeout=request_timeout, max_timeout_tries=max_timeout_tries,
callback=callback, add_to_finish_group=add_to_finish_group, parse_response=parse_response,
parse_on_error=parse_on_error, fail_fast=fail_fast
)
def delete_url(self, host, uri, *, name=None, data=None, headers=None, content_type=None,
connect_timeout=None, request_timeout=None, max_timeout_tries=None,
callback=None, add_to_finish_group=True, parse_response=True, parse_on_error=True, fail_fast=False):
return self._http_client.delete_url(
host, uri, name=name, data=data, headers=headers, content_type=content_type,
connect_timeout=connect_timeout, request_timeout=request_timeout, max_timeout_tries=max_timeout_tries,
callback=callback, add_to_finish_group=add_to_finish_group, parse_response=parse_response,
parse_on_error=parse_on_error, fail_fast=fail_fast
)
class PageHandler(RequestHandler):
preprocessors = ()
def __init__(self, application, request, **kwargs):
self.name = self.__class__.__name__
self.request_id = request.request_id = request_context.get_request_id()
self.config = application.config
self.log = handler_logger
self.text = None
super().__init__(application, request, **kwargs)
self._preprocessor_futures = []
self._exception_hooks = []
for integration in application.available_integrations:
integration.initialize_handler(self)
self.stages_logger = StagesLogger(request, self.statsd_client)
self._debug_access = None
self._render_postprocessors = []
self._postprocessors = []
def __repr__(self):
return '.'.join([self.__module__, self.__class__.__name__])
def prepare(self):
self.active_limit = frontik.handler_active_limit.ActiveHandlersLimit(
self.statsd_client)
self.debug_mode = DebugMode(self)
self.finish_group = AsyncGroup(lambda: None, name='finish')
self.json_producer = self.application.json.get_producer(self)
self.json = self.json_producer.json
self.xml_producer = self.application.xml.get_producer(self)
self.doc = self.xml_producer.doc
self._http_client = self.application.http_client_factory.get_http_client(
self, self.modify_http_client_request) # type: HttpClient
self._handler_finished_notification = self.finish_group.add_notification(
)
super().prepare()
def require_debug_access(self, login=None, passwd=None):
if self._debug_access is None:
if options.debug:
debug_access = True
else:
check_login = login if login is not None else options.debug_login
check_passwd = passwd if passwd is not None else options.debug_password
frontik.auth.check_debug_auth(self, check_login, check_passwd)
debug_access = True
self._debug_access = debug_access
def set_default_headers(self):
self._headers = tornado.httputil.HTTPHeaders({
'Server':
f'Frontik/{frontik_version}',
'X-Request-Id':
self.request_id,
})
def decode_argument(self, value, name=None):
try:
return super().decode_argument(value, name)
except (UnicodeError, tornado.web.HTTPError):
self.log.warning(
'cannot decode utf-8 query parameter, trying other charsets')
try:
return frontik.util.decode_string_from_charset(value)
except UnicodeError:
self.log.exception(
'cannot decode argument, ignoring invalid chars')
return value.decode('utf-8', 'ignore')
def get_body_argument(self, name, default=_ARG_DEFAULT, strip=True):
if self._get_request_mime_type(
self.request) == media_types.APPLICATION_JSON:
if name not in self.json_body and default == _ARG_DEFAULT:
raise tornado.web.MissingArgumentError(name)
result = self.json_body.get(name, default)
if strip and isinstance(result, str):
return result.strip()
return result
if default == _ARG_DEFAULT:
return super().get_body_argument(name, strip=strip)
return super().get_body_argument(name, default, strip)
def _get_request_mime_type(self, request):
content_type = request.headers.get('Content-Type', '')
return re.split(MEDIA_TYPE_PARAMETERS_SEPARATOR_RE, content_type)[0]
def set_status(self, status_code, reason=None):
status_code = _fallback_status_code(status_code)
super().set_status(status_code, reason=reason)
def redirect(self, url, *args, **kwargs):
self.log.info('redirecting to: %s', url)
return super().redirect(url, *args, **kwargs)
def reverse_url(self, name, *args, **kwargs):
return self.application.reverse_url(name, *args, **kwargs)
@property
def json_body(self):
if not hasattr(self, '_json_body'):
self._json_body = self._get_json_body()
return self._json_body
def _get_json_body(self):
try:
return json.loads(self.request.body)
except json.JSONDecodeError as _:
raise JSONBodyParseError()
@classmethod
def add_callback(cls, callback, *args, **kwargs):
IOLoop.current().add_callback(callback, *args, **kwargs)
@classmethod
def add_timeout(cls, deadline, callback, *args, **kwargs):
return IOLoop.current().add_timeout(deadline, callback, *args,
**kwargs)
@staticmethod
def remove_timeout(timeout):
IOLoop.current().remove_timeout(timeout)
@classmethod
def add_future(cls, future, callback):
IOLoop.current().add_future(future, callback)
# Requests handling
def _execute(self, transforms, *args, **kwargs):
request_context.set_handler_name(repr(self))
with stack_context.ExceptionStackContext(
self._stack_context_handle_exception):
return super()._execute(transforms, *args, **kwargs)
@gen.coroutine
def get(self, *args, **kwargs):
yield self._execute_page(self.get_page)
@gen.coroutine
def post(self, *args, **kwargs):
yield self._execute_page(self.post_page)
@gen.coroutine
def head(self, *args, **kwargs):
yield self._execute_page(self.get_page)
@gen.coroutine
def delete(self, *args, **kwargs):
yield self._execute_page(self.delete_page)
@gen.coroutine
def put(self, *args, **kwargs):
yield self._execute_page(self.put_page)
def options(self, *args, **kwargs):
self.__return_405()
@gen.coroutine
def _execute_page(self, page_handler_method):
self.stages_logger.commit_stage('prepare')
preprocessors = _unwrap_preprocessors(
self.preprocessors) + _get_preprocessors(
page_handler_method.__func__)
preprocessors_completed = yield self._run_preprocessors(preprocessors)
if not preprocessors_completed:
self.log.info('page was already finished, skipping page method')
return
yield gen.coroutine(page_handler_method)()
self._handler_finished_notification()
yield self.finish_group.get_finish_future()
render_result = yield self._postprocess()
if render_result is not None:
self.write(render_result)
def get_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def post_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def put_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def delete_page(self):
""" This method can be implemented in the subclass """
self.__return_405()
def __return_405(self):
allowed_methods = [
name for name in ('get', 'post', 'put', 'delete')
if f'{name}_page' in vars(self.__class__)
]
self.set_header('Allow', ', '.join(allowed_methods))
self.set_status(405)
self.finish()
def get_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def post_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def put_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def delete_page_fail_fast(self, request_result: RequestResult):
self.__return_error(request_result.response.code)
def __return_error(self, response_code):
self.send_error(response_code if 300 <= response_code < 500 else 502)
# Finish page
def is_finished(self):
return self._finished
def check_finished(self, callback):
@wraps(callback)
def wrapper(*args, **kwargs):
if self.is_finished():
self.log.warning('page was already finished, %s ignored',
callback)
else:
return callback(*args, **kwargs)
return wrapper
def finish_with_postprocessors(self):
if not self.finish_group.get_finish_future().done():
self.finish_group.abort()
def _cb(future):
if future.result() is not None:
self.finish(future.result())
self.add_future(self._postprocess(), _cb)
@gen.coroutine
def _postprocess(self):
if self._finished:
self.log.info('page was already finished, skipping postprocessors')
return
postprocessors_completed = yield self._run_postprocessors(
self._postprocessors)
self.stages_logger.commit_stage('page')
if not postprocessors_completed:
self.log.info('page was already finished, skipping page producer')
return
if self.text is not None:
renderer = self._generic_producer
elif not self.json.is_empty():
renderer = self.json_producer
else:
renderer = self.xml_producer
self.log.debug('using %s renderer', renderer)
rendered_result = yield renderer()
postprocessed_result = yield self._run_template_postprocessors(
self._render_postprocessors, rendered_result)
return postprocessed_result
def on_connection_close(self):
super().on_connection_close()
self.finish_group.abort()
self.stages_logger.commit_stage('page')
self.stages_logger.flush_stages(408)
self.cleanup()
def on_finish(self):
self.stages_logger.commit_stage('flush')
self.stages_logger.flush_stages(self.get_status())
def register_exception_hook(self, exception_hook):
"""
Adds a function to the list of hooks, which are executed when `log_exception` is called.
`exception_hook` must have the same signature as `log_exception`
"""
self._exception_hooks.append(exception_hook)
def log_exception(self, typ, value, tb):
super().log_exception(typ, value, tb)
for exception_hook in self._exception_hooks:
exception_hook(typ, value, tb)
def _handle_request_exception(self, e):
if isinstance(e, AbortAsyncGroup):
self.log.info('page was aborted, skipping postprocessing')
elif isinstance(e, FinishWithPostprocessors):
if e.wait_finish_group:
self._handler_finished_notification()
self.add_future(self.finish_group.get_finish_future(),
lambda _: self.finish_with_postprocessors())
else:
self.finish_with_postprocessors()
elif isinstance(e, FailFastError):
response = e.failed_request.response
request = e.failed_request.request
if self.log.isEnabledFor(logging.WARNING):
_max_uri_length = 24
request_name = request.get_host(
) + request.uri[:_max_uri_length]
if len(request.uri) > _max_uri_length:
request_name += '...'
if request.name:
request_name = f'{request_name} ({request.name})'
self.log.warning(
'FailFastError: request %s failed with %s code',
request_name, response.code)
try:
error_method_name = f'{self.request.method.lower()}_page_fail_fast'
method = getattr(self, error_method_name, None)
if callable(method):
method(e.failed_request)
else:
self.__return_error(e.failed_request.response.code)
except Exception as exc:
super()._handle_request_exception(exc)
else:
super()._handle_request_exception(e)
def send_error(self, status_code=500, **kwargs):
"""`send_error` is adapted to support `write_error` that can call
`finish` asynchronously.
"""
self.stages_logger.commit_stage('page')
if self._headers_written:
super().send_error(status_code, **kwargs)
return
reason = kwargs.get('reason')
if 'exc_info' in kwargs:
exception = kwargs['exc_info'][1]
if isinstance(exception,
tornado.web.HTTPError) and exception.reason:
reason = exception.reason
else:
exception = None
if not isinstance(exception, HTTPErrorWithPostprocessors):
self.clear()
self.set_status(status_code, reason=reason)
try:
self.write_error(status_code, **kwargs)
except Exception:
self.log.exception('Uncaught exception in write_error')
if not self._finished:
self.finish()
def write_error(self, status_code=500, **kwargs):
"""
`write_error` can call `finish` asynchronously if HTTPErrorWithPostprocessors is raised.
"""
if 'exc_info' in kwargs:
exception = kwargs['exc_info'][1]
else:
exception = None
if isinstance(exception, HTTPErrorWithPostprocessors):
self.finish_with_postprocessors()
return
self.set_header('Content-Type', media_types.TEXT_HTML)
return super().write_error(status_code, **kwargs)
def cleanup(self):
if hasattr(self, 'active_limit'):
self.active_limit.release()
def finish(self, chunk=None):
self.stages_logger.commit_stage('postprocess')
if self._status_code in (204, 304) or (100 <= self._status_code < 200):
self._write_buffer = []
chunk = None
super().finish(chunk)
self.cleanup()
# Preprocessors and postprocessors
def add_preprocessor_future(self, future):
if self._preprocessor_futures is None:
raise Exception(
'preprocessors chain is already finished, calling add_preprocessor_future at this time is incorrect'
)
self._preprocessor_futures.append(future)
return future
@gen.coroutine
def _run_preprocessors(self, preprocessors):
for p in preprocessors:
yield gen.coroutine(p)(self)
if self._finished:
self.log.info(
'page was already finished, breaking preprocessors chain')
return False
yield gen.multi(self._preprocessor_futures)
self._preprocessor_futures = None
if self._finished:
self.log.info(
'page was already finished, breaking preprocessors chain')
return False
return True
@gen.coroutine
def _run_postprocessors(self, postprocessors):
for p in postprocessors:
yield gen.coroutine(p)(self)
if self._finished:
self.log.warning(
'page was already finished, breaking postprocessors chain')
return False
return True
@gen.coroutine
def _run_template_postprocessors(self, postprocessors, rendered_template):
for p in postprocessors:
rendered_template = yield gen.coroutine(p)(self, rendered_template)
if self._finished:
self.log.warning(
'page was already finished, breaking postprocessors chain')
return None
return rendered_template
def add_render_postprocessor(self, postprocessor):
self._render_postprocessors.append(postprocessor)
def add_postprocessor(self, postprocessor):
self._postprocessors.append(postprocessor)
# Producers
async def _generic_producer(self):
self.log.debug('finishing plaintext')
if self._headers.get('Content-Type') is None:
self.set_header('Content-Type', media_types.TEXT_HTML)
return self.text
def xml_from_file(self, filename):
return self.xml_producer.xml_from_file(filename)
def set_xsl(self, filename):
return self.xml_producer.set_xsl(filename)
def set_template(self, filename):
return self.json_producer.set_template(filename)
# HTTP client methods
def modify_http_client_request(self,
balanced_request: 'BalancedHttpRequest'):
if self.debug_mode.pass_debug:
balanced_request.headers[DEBUG_HEADER_NAME] = 'true'
# debug_timestamp is added to avoid caching of debug responses
balanced_request.uri = make_url(balanced_request.uri,
debug_timestamp=int(time.time()))
for header_name in ('Authorization', DEBUG_AUTH_HEADER_NAME):
authorization = self.request.headers.get(header_name)
if authorization is not None:
balanced_request.headers[header_name] = authorization
def group(self, futures, callback=None, name=None):
group_future = Future()
results_holder = {}
def group_callback():
if callable(callback):
callback(results_holder)
group_future.set_result(results_holder)
def future_callback(name, future):
results_holder[name] = future.result()
async_group = AsyncGroup(self.finish_group.add(
self.check_finished(group_callback)),
name=name)
for name, future in futures.items():
if future.done():
future_callback(name, future)
else:
self.add_future(
future, async_group.add(partial(future_callback, name)))
async_group.try_finish_async()
return group_future
def get_url(self,
host,
uri,
*,
name=None,
data=None,
headers=None,
follow_redirects=True,
connect_timeout=None,
request_timeout=None,
max_timeout_tries=None,
callback=None,
waited=True,
parse_response=True,
parse_on_error=True,
fail_fast=False):
fail_fast = _fail_fast_policy(fail_fast, waited, host, uri)
client_method = lambda callback: self._http_client.get_url(
host,
uri,
name=name,
data=data,
headers=headers,
follow_redirects=follow_redirects,
connect_timeout=connect_timeout,
request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries,
callback=callback,
parse_response=parse_response,
parse_on_error=parse_on_error,
fail_fast=fail_fast)
return self._execute_http_client_method(host, uri, client_method,
waited, callback)
def head_url(self,
host,
uri,
*,
name=None,
data=None,
headers=None,
follow_redirects=True,
connect_timeout=None,
request_timeout=None,
max_timeout_tries=None,
callback=None,
waited=True,
fail_fast=False):
fail_fast = _fail_fast_policy(fail_fast, waited, host, uri)
client_method = lambda callback: self._http_client.head_url(
host,
uri,
data=data,
name=name,
headers=headers,
follow_redirects=follow_redirects,
connect_timeout=connect_timeout,
request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries,
callback=callback,
fail_fast=fail_fast)
return self._execute_http_client_method(host, uri, client_method,
waited, callback)
def post_url(self,
host,
uri,
*,
name=None,
data='',
headers=None,
files=None,
content_type=None,
follow_redirects=True,
connect_timeout=None,
request_timeout=None,
max_timeout_tries=None,
idempotent=False,
callback=None,
waited=True,
parse_response=True,
parse_on_error=True,
fail_fast=False):
fail_fast = _fail_fast_policy(fail_fast, waited, host, uri)
client_method = lambda callback: self._http_client.post_url(
host,
uri,
data=data,
name=name,
headers=headers,
files=files,
content_type=content_type,
follow_redirects=follow_redirects,
connect_timeout=connect_timeout,
request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries,
idempotent=idempotent,
callback=callback,
parse_response=parse_response,
parse_on_error=parse_on_error,
fail_fast=fail_fast)
return self._execute_http_client_method(host, uri, client_method,
waited, callback)
def put_url(self,
host,
uri,
*,
name=None,
data='',
headers=None,
content_type=None,
connect_timeout=None,
request_timeout=None,
max_timeout_tries=None,
callback=None,
waited=True,
parse_response=True,
parse_on_error=True,
fail_fast=False):
fail_fast = _fail_fast_policy(fail_fast, waited, host, uri)
client_method = lambda callback: self._http_client.put_url(
host,
uri,
name=name,
data=data,
headers=headers,
content_type=content_type,
connect_timeout=connect_timeout,
request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries,
callback=callback,
parse_response=parse_response,
parse_on_error=parse_on_error,
fail_fast=fail_fast)
return self._execute_http_client_method(host, uri, client_method,
waited, callback)
def delete_url(self,
host,
uri,
*,
name=None,
data=None,
headers=None,
content_type=None,
connect_timeout=None,
request_timeout=None,
max_timeout_tries=None,
callback=None,
waited=True,
parse_response=True,
parse_on_error=True,
fail_fast=False):
fail_fast = _fail_fast_policy(fail_fast, waited, host, uri)
client_method = lambda callback: self._http_client.delete_url(
host,
uri,
name=name,
data=data,
headers=headers,
content_type=content_type,
connect_timeout=connect_timeout,
request_timeout=request_timeout,
max_timeout_tries=max_timeout_tries,
callback=callback,
parse_response=parse_response,
parse_on_error=parse_on_error,
fail_fast=fail_fast)
return self._execute_http_client_method(host, uri, client_method,
waited, callback)
def _execute_http_client_method(self, host, uri, client_method, waited,
callback):
if waited and (self.is_finished() or self.finish_group.is_finished()):
handler_logger.info(
'attempted to make waited http request to %s %s in finished handler, ignoring',
host, uri)
future = Future()
future.set_exception(AbortAsyncGroup())
return future
if waited and callable(callback):
callback = self.check_finished(callback)
future = client_method(callback)
if waited:
self.finish_group.add_future(future)
return future