sanic/sanic/app.py
2018-03-12 20:21:59 +01:00

875 lines
34 KiB
Python

import os
import logging
import logging.config
import re
import warnings
from asyncio import get_event_loop, ensure_future, CancelledError
from collections import deque, defaultdict
from functools import partial
from inspect import getmodulename, isawaitable, signature, stack
from traceback import format_exc
from urllib.parse import urlencode, urlunparse
from ssl import create_default_context, Purpose
from sanic.config import Config
from sanic.constants import HTTP_METHODS
from sanic.exceptions import ServerError, URLBuildError, SanicException
from sanic.handlers import ErrorHandler
from sanic.log import logger, error_logger, LOGGING_CONFIG_DEFAULTS
from sanic.response import HTTPResponse, StreamingHTTPResponse
from sanic.router import Router
from sanic.server import serve, serve_multiple, HttpProtocol, Signal
from sanic.static import register as static_register
from sanic.testing import SanicTestClient
from sanic.views import CompositionView
from sanic.websocket import WebSocketProtocol, ConnectionClosed
import sanic.reloader_helpers as reloader_helpers
class Sanic:
def __init__(self, name=None, router=None, error_handler=None,
load_env=True, request_class=None,
strict_slashes=False, log_config=None,
configure_logging=True):
# Get name from previous stack frame
if name is None:
frame_records = stack()[1]
name = getmodulename(frame_records[1])
# logging
if configure_logging:
logging.config.dictConfig(log_config or LOGGING_CONFIG_DEFAULTS)
self.name = name
self.router = router or Router()
self.request_class = request_class
self.error_handler = error_handler or ErrorHandler()
self.config = Config(load_env=load_env)
self.request_middleware = deque()
self.response_middleware = deque()
self.blueprints = {}
self._blueprint_order = []
self.configure_logging = configure_logging
self.debug = None
self.sock = None
self.strict_slashes = strict_slashes
self.listeners = defaultdict(list)
self.is_running = False
self.is_request_stream = False
self.websocket_enabled = False
self.websocket_tasks = set()
# Register alternative method names
self.go_fast = self.run
@property
def loop(self):
"""Synonymous with asyncio.get_event_loop().
Only supported when using the `app.run` method.
"""
if not self.is_running:
raise SanicException(
'Loop can only be retrieved after the app has started '
'running. Not supported with `create_server` function')
return get_event_loop()
# -------------------------------------------------------------------- #
# Registration
# -------------------------------------------------------------------- #
def add_task(self, task):
"""Schedule a task to run later, after the loop has started.
Different from asyncio.ensure_future in that it does not
also return a future, and the actual ensure_future call
is delayed until before server start.
:param task: future, couroutine or awaitable
"""
try:
if callable(task):
try:
self.loop.create_task(task(self))
except TypeError:
self.loop.create_task(task())
else:
self.loop.create_task(task)
except SanicException:
@self.listener('before_server_start')
def run(app, loop):
if callable(task):
try:
loop.create_task(task(self))
except TypeError:
loop.create_task(task())
else:
loop.create_task(task)
# Decorator
def listener(self, event):
"""Create a listener from a decorated function.
:param event: event to listen to
"""
def decorator(listener):
self.listeners[event].append(listener)
return listener
return decorator
def register_listener(self, listener, event):
"""
Register the listener for a given event.
Args:
listener: callable i.e. setup_db(app, loop)
event: when to register listener i.e. 'before_server_start'
Returns: listener
"""
return self.listener(event)(listener)
# Decorator
def route(self, uri, methods=frozenset({'GET'}), host=None,
strict_slashes=None, stream=False, version=None, name=None):
"""Decorate a function to be registered as a route
:param uri: path of the URL
:param methods: list or tuple of methods allowed
:param host:
:param strict_slashes:
:param stream:
:param version:
:param name: user defined route name for url_for
:return: decorated function
"""
# Fix case where the user did not prefix the URL with a /
# and will probably get confused as to why it's not working
if not uri.startswith('/'):
uri = '/' + uri
if stream:
self.is_request_stream = True
if strict_slashes is None:
strict_slashes = self.strict_slashes
def response(handler):
args = [key for key in signature(handler).parameters.keys()]
if args:
if stream:
handler.is_stream = stream
self.router.add(uri=uri, methods=methods, handler=handler,
host=host, strict_slashes=strict_slashes,
version=version, name=name)
return handler
else:
raise ValueError(
'Required parameter `request` missing'
'in the {0}() route?'.format(
handler.__name__))
return response
# Shorthand method decorators
def get(self, uri, host=None, strict_slashes=None, version=None,
name=None):
return self.route(uri, methods=frozenset({"GET"}), host=host,
strict_slashes=strict_slashes, version=version,
name=name)
def post(self, uri, host=None, strict_slashes=None, stream=False,
version=None, name=None):
return self.route(uri, methods=frozenset({"POST"}), host=host,
strict_slashes=strict_slashes, stream=stream,
version=version, name=name)
def put(self, uri, host=None, strict_slashes=None, stream=False,
version=None, name=None):
return self.route(uri, methods=frozenset({"PUT"}), host=host,
strict_slashes=strict_slashes, stream=stream,
version=version, name=name)
def head(self, uri, host=None, strict_slashes=None, version=None,
name=None):
return self.route(uri, methods=frozenset({"HEAD"}), host=host,
strict_slashes=strict_slashes, version=version,
name=name)
def options(self, uri, host=None, strict_slashes=None, version=None,
name=None):
return self.route(uri, methods=frozenset({"OPTIONS"}), host=host,
strict_slashes=strict_slashes, version=version,
name=name)
def patch(self, uri, host=None, strict_slashes=None, stream=False,
version=None, name=None):
return self.route(uri, methods=frozenset({"PATCH"}), host=host,
strict_slashes=strict_slashes, stream=stream,
version=version, name=name)
def delete(self, uri, host=None, strict_slashes=None, version=None,
name=None):
return self.route(uri, methods=frozenset({"DELETE"}), host=host,
strict_slashes=strict_slashes, version=version,
name=name)
def add_route(self, handler, uri, methods=frozenset({'GET'}), host=None,
strict_slashes=None, version=None, name=None, stream=False):
"""A helper method to register class instance or
functions as a handler to the application url
routes.
:param handler: function or class instance
:param uri: path of the URL
:param methods: list or tuple of methods allowed, these are overridden
if using a HTTPMethodView
:param host:
:param strict_slashes:
:param version:
:param name: user defined route name for url_for
:param stream: boolean specifying if the handler is a stream handler
:return: function or class instance
"""
# Handle HTTPMethodView differently
if hasattr(handler, 'view_class'):
methods = set()
for method in HTTP_METHODS:
_handler = getattr(handler.view_class, method.lower(), None)
if _handler:
methods.add(method)
if hasattr(_handler, 'is_stream'):
stream = True
# handle composition view differently
if isinstance(handler, CompositionView):
methods = handler.handlers.keys()
for _handler in handler.handlers.values():
if hasattr(_handler, 'is_stream'):
stream = True
break
if strict_slashes is None:
strict_slashes = self.strict_slashes
self.route(uri=uri, methods=methods, host=host,
strict_slashes=strict_slashes, stream=stream,
version=version, name=name)(handler)
return handler
# Decorator
def websocket(self, uri, host=None, strict_slashes=None,
subprotocols=None, name=None):
"""Decorate a function to be registered as a websocket route
:param uri: path of the URL
:param subprotocols: optional list of strings with the supported
subprotocols
:param host:
:return: decorated function
"""
self.enable_websocket()
# Fix case where the user did not prefix the URL with a /
# and will probably get confused as to why it's not working
if not uri.startswith('/'):
uri = '/' + uri
if strict_slashes is None:
strict_slashes = self.strict_slashes
def response(handler):
async def websocket_handler(request, *args, **kwargs):
request.app = self
try:
protocol = request.transport.get_protocol()
except AttributeError:
# On Python3.5 the Transport classes in asyncio do not
# have a get_protocol() method as in uvloop
protocol = request.transport._protocol
ws = await protocol.websocket_handshake(request, subprotocols)
# schedule the application handler
# its future is kept in self.websocket_tasks in case it
# needs to be cancelled due to the server being stopped
fut = ensure_future(handler(request, ws, *args, **kwargs))
self.websocket_tasks.add(fut)
try:
await fut
except (CancelledError, ConnectionClosed):
pass
self.websocket_tasks.remove(fut)
await ws.close()
self.router.add(uri=uri, handler=websocket_handler,
methods=frozenset({'GET'}), host=host,
strict_slashes=strict_slashes, name=name)
return handler
return response
def add_websocket_route(self, handler, uri, host=None,
strict_slashes=None, name=None):
"""A helper method to register a function as a websocket route."""
if strict_slashes is None:
strict_slashes = self.strict_slashes
return self.websocket(uri, host=host, strict_slashes=strict_slashes,
name=name)(handler)
def enable_websocket(self, enable=True):
"""Enable or disable the support for websocket.
Websocket is enabled automatically if websocket routes are
added to the application.
"""
if not self.websocket_enabled:
# if the server is stopped, we want to cancel any ongoing
# websocket tasks, to allow the server to exit promptly
@self.listener('before_server_stop')
def cancel_websocket_tasks(app, loop):
for task in self.websocket_tasks:
task.cancel()
self.websocket_enabled = enable
def remove_route(self, uri, clean_cache=True, host=None):
self.router.remove(uri, clean_cache, host)
# Decorator
def exception(self, *exceptions):
"""Decorate a function to be registered as a handler for exceptions
:param exceptions: exceptions
:return: decorated function
"""
def response(handler):
for exception in exceptions:
if isinstance(exception, (tuple, list)):
for e in exception:
self.error_handler.add(e, handler)
else:
self.error_handler.add(exception, handler)
return handler
return response
def register_middleware(self, middleware, attach_to='request'):
if attach_to == 'request':
self.request_middleware.append(middleware)
if attach_to == 'response':
self.response_middleware.appendleft(middleware)
return middleware
# Decorator
def middleware(self, middleware_or_request):
"""Decorate and register middleware to be called before a request.
Can either be called as @app.middleware or @app.middleware('request')
"""
# Detect which way this was called, @middleware or @middleware('AT')
if callable(middleware_or_request):
return self.register_middleware(middleware_or_request)
else:
return partial(self.register_middleware,
attach_to=middleware_or_request)
# Static Files
def static(self, uri, file_or_directory, pattern=r'/?.+',
use_modified_since=True, use_content_range=False,
stream_large_files=False, name='static', host=None,
strict_slashes=None):
"""Register a root to serve files from. The input can either be a
file or a directory. See
"""
static_register(self, uri, file_or_directory, pattern,
use_modified_since, use_content_range,
stream_large_files, name, host, strict_slashes)
def blueprint(self, blueprint, **options):
"""Register a blueprint on the application.
:param blueprint: Blueprint object or (list, tuple) thereof
:param options: option dictionary with blueprint defaults
:return: Nothing
"""
if isinstance(blueprint, (list, tuple)):
for item in blueprint:
self.blueprint(item, **options)
return
if blueprint.name in self.blueprints:
assert self.blueprints[blueprint.name] is blueprint, \
'A blueprint with the name "%s" is already registered. ' \
'Blueprint names must be unique.' % \
(blueprint.name,)
else:
self.blueprints[blueprint.name] = blueprint
self._blueprint_order.append(blueprint)
blueprint.register(self, options)
def register_blueprint(self, *args, **kwargs):
# TODO: deprecate 1.0
if self.debug:
warnings.simplefilter('default')
warnings.warn("Use of register_blueprint will be deprecated in "
"version 1.0. Please use the blueprint method"
" instead",
DeprecationWarning)
return self.blueprint(*args, **kwargs)
def url_for(self, view_name: str, **kwargs):
"""Build a URL based on a view name and the values provided.
In order to build a URL, all request parameters must be supplied as
keyword arguments, and each parameter must pass the test for the
specified parameter type. If these conditions are not met, a
`URLBuildError` will be thrown.
Keyword arguments that are not request parameters will be included in
the output URL's query string.
:param view_name: string referencing the view name
:param \*\*kwargs: keys and values that are used to build request
parameters and query string arguments.
:return: the built URL
Raises:
URLBuildError
"""
# find the route by the supplied view name
kw = {}
# special static files url_for
if view_name == 'static':
kw.update(name=kwargs.pop('name', 'static'))
elif view_name.endswith('.static'): # blueprint.static
kwargs.pop('name', None)
kw.update(name=view_name)
uri, route = self.router.find_route_by_view_name(view_name, **kw)
if not (uri and route):
raise URLBuildError('Endpoint with name `{}` was not found'.format(
view_name))
if view_name == 'static' or view_name.endswith('.static'):
filename = kwargs.pop('filename', None)
# it's static folder
if '<file_uri:' in uri:
folder_ = uri.split('<file_uri:', 1)[0]
if folder_.endswith('/'):
folder_ = folder_[:-1]
if filename.startswith('/'):
filename = filename[1:]
uri = '{}/{}'.format(folder_, filename)
if uri != '/' and uri.endswith('/'):
uri = uri[:-1]
out = uri
# find all the parameters we will need to build in the URL
matched_params = re.findall(
self.router.parameter_pattern, uri)
# _method is only a placeholder now, don't know how to support it
kwargs.pop('_method', None)
anchor = kwargs.pop('_anchor', '')
# _external need SERVER_NAME in config or pass _server arg
external = kwargs.pop('_external', False)
scheme = kwargs.pop('_scheme', '')
if scheme and not external:
raise ValueError('When specifying _scheme, _external must be True')
netloc = kwargs.pop('_server', None)
if netloc is None and external:
netloc = self.config.get('SERVER_NAME', '')
if external:
if not scheme:
if ':' in netloc[:8]:
scheme = netloc[:8].split(':', 1)[0]
else:
scheme = 'http'
if '://' in netloc[:8]:
netloc = netloc.split('://', 1)[-1]
for match in matched_params:
name, _type, pattern = self.router.parse_parameter_string(
match)
# we only want to match against each individual parameter
specific_pattern = '^{}$'.format(pattern)
supplied_param = None
if name in kwargs:
supplied_param = kwargs.get(name)
del kwargs[name]
else:
raise URLBuildError(
'Required parameter `{}` was not passed to url_for'.format(
name))
supplied_param = str(supplied_param)
# determine if the parameter supplied by the caller passes the test
# in the URL
passes_pattern = re.match(specific_pattern, supplied_param)
if not passes_pattern:
if _type != str:
msg = (
'Value "{}" for parameter `{}` does not '
'match pattern for type `{}`: {}'.format(
supplied_param, name, _type.__name__, pattern))
else:
msg = (
'Value "{}" for parameter `{}` '
'does not satisfy pattern {}'.format(
supplied_param, name, pattern))
raise URLBuildError(msg)
# replace the parameter in the URL with the supplied value
replacement_regex = '(<{}.*?>)'.format(name)
out = re.sub(
replacement_regex, supplied_param, out)
# parse the remainder of the keyword arguments into a querystring
query_string = urlencode(kwargs, doseq=True) if kwargs else ''
# scheme://netloc/path;parameters?query#fragment
out = urlunparse((scheme, netloc, out, '', query_string, anchor))
return out
# -------------------------------------------------------------------- #
# Request Handling
# -------------------------------------------------------------------- #
def converted_response_type(self, response):
pass
async def handle_request(self, request, write_callback, stream_callback):
"""Take a request from the HTTP Server and return a response object
to be sent back The HTTP Server only expects a response object, so
exception handling must be done here
:param request: HTTP Request object
:param write_callback: Synchronous response function to be
called with the response as the only argument
:param stream_callback: Coroutine that handles streaming a
StreamingHTTPResponse if produced by the handler.
:return: Nothing
"""
try:
# -------------------------------------------- #
# Request Middleware
# -------------------------------------------- #
request.app = self
response = await self._run_request_middleware(request)
# No middleware results
if not response:
# -------------------------------------------- #
# Execute Handler
# -------------------------------------------- #
# Fetch handler from router
handler, args, kwargs, uri = self.router.get(request)
request.uri_template = uri
if handler is None:
raise ServerError(
("'None' was returned while requesting a "
"handler from the router"))
# Run response handler
response = handler(request, *args, **kwargs)
if isawaitable(response):
response = await response
except Exception as e:
# -------------------------------------------- #
# Response Generation Failed
# -------------------------------------------- #
try:
response = self.error_handler.response(request, e)
if isawaitable(response):
response = await response
except Exception as e:
if isinstance(e, SanicException):
response = self.error_handler.default(request=request,
exception=e)
elif self.debug:
response = HTTPResponse(
"Error while handling error: {}\nStack: {}".format(
e, format_exc()), status=500)
else:
response = HTTPResponse(
"An error occurred while handling an error",
status=500)
finally:
# -------------------------------------------- #
# Response Middleware
# -------------------------------------------- #
try:
response = await self._run_response_middleware(request,
response)
except BaseException:
error_logger.exception(
'Exception occurred in one of response middleware handlers'
)
# pass the response to the correct callback
if isinstance(response, StreamingHTTPResponse):
await stream_callback(response)
else:
write_callback(response)
# -------------------------------------------------------------------- #
# Testing
# -------------------------------------------------------------------- #
@property
def test_client(self):
return SanicTestClient(self)
# -------------------------------------------------------------------- #
# Execution
# -------------------------------------------------------------------- #
def run(self, host=None, port=None, debug=False, ssl=None,
sock=None, workers=1, protocol=None,
backlog=100, stop_event=None, register_sys_signals=True,
access_log=True, auto_reload=False):
"""Run the HTTP Server and listen until keyboard interrupt or term
signal. On termination, drain connections before closing.
:param host: Address to host on
:param port: Port to host on
:param debug: Enables debug output (slows server)
:param ssl: SSLContext, or location of certificate and key
for SSL encryption of worker(s)
:param sock: Socket for the server to accept connections from
:param workers: Number of processes
received before it is respected
:param backlog:
:param stop_event:
:param register_sys_signals:
:param protocol: Subclass of asyncio protocol class
:return: Nothing
"""
if sock is None:
host, port = host or "127.0.0.1", port or 8000
if protocol is None:
protocol = (WebSocketProtocol if self.websocket_enabled
else HttpProtocol)
if stop_event is not None:
if debug:
warnings.simplefilter('default')
warnings.warn("stop_event will be removed from future versions.",
DeprecationWarning)
server_settings = self._helper(
host=host, port=port, debug=debug, ssl=ssl, sock=sock,
workers=workers, protocol=protocol, backlog=backlog,
register_sys_signals=register_sys_signals,
access_log=access_log, auto_reload=auto_reload)
try:
self.is_running = True
if workers == 1:
if auto_reload and os.name != 'posix':
# This condition must be removed after implementing
# auto reloader for other operating systems.
raise NotImplementedError
if auto_reload and \
os.environ.get('SANIC_SERVER_RUNNING') != 'true':
reloader_helpers.watchdog(2)
else:
serve(**server_settings)
else:
serve_multiple(server_settings, workers)
except BaseException:
error_logger.exception(
'Experienced exception while trying to serve')
raise
finally:
self.is_running = False
logger.info("Server Stopped")
def stop(self):
"""This kills the Sanic"""
get_event_loop().stop()
def __call__(self):
"""gunicorn compatibility"""
return self
async def create_server(self, host=None, port=None, debug=False,
ssl=None, sock=None, protocol=None,
backlog=100, stop_event=None,
access_log=True):
"""Asynchronous version of `run`.
NOTE: This does not support multiprocessing and is not the preferred
way to run a Sanic application.
"""
if sock is None:
host, port = host or "127.0.0.1", port or 8000
if protocol is None:
protocol = (WebSocketProtocol if self.websocket_enabled
else HttpProtocol)
if stop_event is not None:
if debug:
warnings.simplefilter('default')
warnings.warn("stop_event will be removed from future versions.",
DeprecationWarning)
server_settings = self._helper(
host=host, port=port, debug=debug, ssl=ssl, sock=sock,
loop=get_event_loop(), protocol=protocol,
backlog=backlog, run_async=True,
access_log=access_log)
# Trigger before_start events
await self.trigger_events(
server_settings.get('before_start', []),
server_settings.get('loop')
)
return await serve(**server_settings)
async def trigger_events(self, events, loop):
"""Trigger events (functions or async)
:param events: one or more sync or async functions to execute
:param loop: event loop
"""
for event in events:
result = event(loop)
if isawaitable(result):
await result
async def _run_request_middleware(self, request):
# The if improves speed. I don't know why
if self.request_middleware:
for middleware in self.request_middleware:
response = middleware(request)
if isawaitable(response):
response = await response
if response:
return response
return None
async def _run_response_middleware(self, request, response):
if self.response_middleware:
for middleware in self.response_middleware:
_response = middleware(request, response)
if isawaitable(_response):
_response = await _response
if _response:
response = _response
break
return response
def _helper(self, host=None, port=None, debug=False,
ssl=None, sock=None, workers=1, loop=None,
protocol=HttpProtocol, backlog=100, stop_event=None,
register_sys_signals=True, run_async=False, access_log=True,
auto_reload=False):
"""Helper function used by `run` and `create_server`."""
if isinstance(ssl, dict):
# try common aliaseses
cert = ssl.get('cert') or ssl.get('certificate')
key = ssl.get('key') or ssl.get('keyfile')
if cert is None or key is None:
raise ValueError("SSLContext or certificate and key required.")
context = create_default_context(purpose=Purpose.CLIENT_AUTH)
context.load_cert_chain(cert, keyfile=key)
ssl = context
if stop_event is not None:
if debug:
warnings.simplefilter('default')
warnings.warn("stop_event will be removed from future versions.",
DeprecationWarning)
self.error_handler.debug = debug
self.debug = debug
server_settings = {
'protocol': protocol,
'request_class': self.request_class,
'is_request_stream': self.is_request_stream,
'router': self.router,
'host': host,
'port': port,
'sock': sock,
'ssl': ssl,
'signal': Signal(),
'debug': debug,
'request_handler': self.handle_request,
'error_handler': self.error_handler,
'request_timeout': self.config.REQUEST_TIMEOUT,
'response_timeout': self.config.RESPONSE_TIMEOUT,
'keep_alive_timeout': self.config.KEEP_ALIVE_TIMEOUT,
'request_max_size': self.config.REQUEST_MAX_SIZE,
'keep_alive': self.config.KEEP_ALIVE,
'loop': loop,
'register_sys_signals': register_sys_signals,
'backlog': backlog,
'access_log': access_log,
'websocket_max_size': self.config.WEBSOCKET_MAX_SIZE,
'websocket_max_queue': self.config.WEBSOCKET_MAX_QUEUE,
'websocket_read_limit': self.config.WEBSOCKET_READ_LIMIT,
'websocket_write_limit': self.config.WEBSOCKET_WRITE_LIMIT,
'graceful_shutdown_timeout': self.config.GRACEFUL_SHUTDOWN_TIMEOUT
}
# -------------------------------------------- #
# Register start/stop events
# -------------------------------------------- #
for event_name, settings_name, reverse in (
("before_server_start", "before_start", False),
("after_server_start", "after_start", False),
("before_server_stop", "before_stop", True),
("after_server_stop", "after_stop", True),
):
listeners = self.listeners[event_name].copy()
if reverse:
listeners.reverse()
# Prepend sanic to the arguments when listeners are triggered
listeners = [partial(listener, self) for listener in listeners]
server_settings[settings_name] = listeners
if self.configure_logging and debug:
logger.setLevel(logging.DEBUG)
if self.config.LOGO is not None and \
os.environ.get('SANIC_SERVER_RUNNING') != 'true':
logger.debug(self.config.LOGO)
if run_async:
server_settings['run_async'] = True
# Serve
if host and port and os.environ.get('SANIC_SERVER_RUNNING') != 'true':
proto = "http"
if ssl is not None:
proto = "https"
logger.info('Goin\' Fast @ {}://{}:{}'.format(proto, host, port))
return server_settings