/
wsproto_impl.py
324 lines (281 loc) · 11.7 KB
/
wsproto_impl.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
import asyncio
import logging
from urllib.parse import unquote
import h11
import wsproto
from wsproto import ConnectionType, events
from wsproto.connection import ConnectionState
from wsproto.extensions import PerMessageDeflate
from wsproto.utilities import RemoteProtocolError
from uvicorn.logging import TRACE_LOG_LEVEL
from uvicorn.protocols.utils import (
get_local_addr,
get_path_with_query_string,
get_remote_addr,
is_ssl,
)
class WSProtocol(asyncio.Protocol):
def __init__(self, config, server_state, _loop=None):
if not config.loaded:
config.load()
self.config = config
self.app = config.loaded_app
self.loop = _loop or asyncio.get_event_loop()
self.logger = logging.getLogger("uvicorn.error")
self.root_path = config.root_path
# Shared server state
self.connections = server_state.connections
self.tasks = server_state.tasks
self.default_headers = server_state.default_headers
# Connection state
self.transport = None
self.server = None
self.client = None
self.scheme = None
# WebSocket state
self.connect_event = None
self.queue = asyncio.Queue()
self.handshake_complete = False
self.close_sent = False
self.conn = wsproto.WSConnection(connection_type=ConnectionType.SERVER)
self.read_paused = False
self.writable = asyncio.Event()
self.writable.set()
# Buffers
self.bytes = b""
self.text = ""
# Protocol interface
def connection_made(self, transport):
self.connections.add(self)
self.transport = transport
self.server = get_local_addr(transport)
self.client = get_remote_addr(transport)
self.scheme = "wss" if is_ssl(transport) else "ws"
if self.logger.level <= TRACE_LOG_LEVEL:
prefix = "%s:%d - " % tuple(self.client) if self.client else ""
self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection made", prefix)
def connection_lost(self, exc):
self.queue.put_nowait({"type": "websocket.disconnect"})
self.connections.remove(self)
if self.logger.level <= TRACE_LOG_LEVEL:
prefix = "%s:%d - " % tuple(self.client) if self.client else ""
self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection lost", prefix)
if exc is None:
self.transport.close()
def eof_received(self):
pass
def data_received(self, data):
try:
self.conn.receive_data(data)
except RemoteProtocolError as err:
self.transport.write(self.conn.send(err.event_hint))
self.transport.close()
else:
self.handle_events()
def handle_events(self):
for event in self.conn.events():
if isinstance(event, events.Request):
self.handle_connect(event)
elif isinstance(event, events.TextMessage):
self.handle_text(event)
elif isinstance(event, events.BytesMessage):
self.handle_bytes(event)
elif isinstance(event, events.RejectConnection):
self.handle_no_connect(event)
elif isinstance(event, events.RejectData):
self.handle_no_connect(event)
elif isinstance(event, events.CloseConnection):
self.handle_close(event)
elif isinstance(event, events.Ping):
self.handle_ping(event)
def pause_writing(self):
"""
Called by the transport when the write buffer exceeds the high water mark.
"""
self.writable.clear()
def resume_writing(self):
"""
Called by the transport when the write buffer drops below the low water mark.
"""
self.writable.set()
def shutdown(self):
self.queue.put_nowait({"type": "websocket.disconnect", "code": 1012})
output = self.conn.send(wsproto.events.CloseConnection(code=1012))
self.transport.write(output)
self.transport.close()
def on_task_complete(self, task):
self.tasks.discard(task)
# Event handlers
def handle_connect(self, event):
self.connect_event = event
headers = [(b"host", event.host.encode())]
headers += [(key.lower(), value) for key, value in event.extra_headers]
raw_path, _, query_string = event.target.partition("?")
self.scope = {
"type": "websocket",
"asgi": {"version": self.config.asgi_version, "spec_version": "2.3"},
"http_version": "1.1",
"scheme": self.scheme,
"server": self.server,
"client": self.client,
"root_path": self.root_path,
"path": unquote(raw_path),
"raw_path": raw_path.encode("ascii"),
"query_string": query_string.encode("ascii"),
"headers": headers,
"subprotocols": event.subprotocols,
}
self.queue.put_nowait({"type": "websocket.connect"})
task = self.loop.create_task(self.run_asgi())
task.add_done_callback(self.on_task_complete)
self.tasks.add(task)
def handle_no_connect(self, event):
headers = [
(b"content-type", b"text/plain; charset=utf-8"),
(b"connection", b"close"),
]
msg = h11.Response(status_code=400, headers=headers, reason="Bad Request")
output = self.conn.send(msg)
msg = h11.Data(data=event.reason.encode("utf-8"))
output += self.conn.send(msg)
msg = h11.EndOfMessage()
output += self.conn.send(msg)
self.transport.write(output)
self.transport.close()
def handle_text(self, event):
self.text += event.data
if event.message_finished:
self.queue.put_nowait({"type": "websocket.receive", "text": self.text})
self.text = ""
if not self.read_paused:
self.read_paused = True
self.transport.pause_reading()
def handle_bytes(self, event):
self.bytes += event.data
# todo: we may want to guard the size of self.bytes and self.text
if event.message_finished:
self.queue.put_nowait({"type": "websocket.receive", "bytes": self.bytes})
self.bytes = b""
if not self.read_paused:
self.read_paused = True
self.transport.pause_reading()
def handle_close(self, event):
if self.conn.state == ConnectionState.REMOTE_CLOSING:
self.transport.write(self.conn.send(event.response()))
self.queue.put_nowait({"type": "websocket.disconnect", "code": event.code})
self.transport.close()
def handle_ping(self, event):
self.transport.write(self.conn.send(event.response()))
def send_500_response(self):
headers = [
(b"content-type", b"text/plain; charset=utf-8"),
(b"connection", b"close"),
]
if self.conn.connection is None:
output = self.conn.send(wsproto.events.RejectConnection(status_code=500))
else:
msg = h11.Response(
status_code=500, headers=headers, reason="Internal Server Error"
)
output = self.conn.send(msg)
msg = h11.Data(data=b"Internal Server Error")
output += self.conn.send(msg)
msg = h11.EndOfMessage()
output += self.conn.send(msg)
self.transport.write(output)
async def run_asgi(self):
try:
result = await self.app(self.scope, self.receive, self.send)
except BaseException as exc:
msg = "Exception in ASGI application\n"
self.logger.error(msg, exc_info=exc)
if not self.handshake_complete:
self.send_500_response()
self.transport.close()
else:
if not self.handshake_complete:
msg = "ASGI callable returned without completing handshake."
self.logger.error(msg)
self.send_500_response()
self.transport.close()
elif result is not None:
msg = "ASGI callable should return None, but returned '%s'."
self.logger.error(msg, result)
self.transport.close()
async def send(self, message):
await self.writable.wait()
message_type = message["type"]
if not self.handshake_complete:
if message_type == "websocket.accept":
self.logger.info(
'%s - "WebSocket %s" [accepted]',
self.scope["client"],
get_path_with_query_string(self.scope),
)
self.handshake_complete = True
subprotocol = message.get("subprotocol")
extra_headers = self.default_headers + list(message.get("headers", []))
extensions = []
if self.config.ws_per_message_deflate:
extensions.append(PerMessageDeflate())
output = self.conn.send(
wsproto.events.AcceptConnection(
subprotocol=subprotocol,
extensions=extensions,
extra_headers=extra_headers,
)
)
self.transport.write(output)
elif message_type == "websocket.close":
self.queue.put_nowait({"type": "websocket.disconnect", "code": None})
self.logger.info(
'%s - "WebSocket %s" 403',
self.scope["client"],
get_path_with_query_string(self.scope),
)
self.handshake_complete = True
self.close_sent = True
msg = events.RejectConnection(status_code=403, headers=[])
output = self.conn.send(msg)
self.transport.write(output)
self.transport.close()
else:
msg = (
"Expected ASGI message 'websocket.accept' or 'websocket.close', "
"but got '%s'."
)
raise RuntimeError(msg % message_type)
elif not self.close_sent:
if message_type == "websocket.send":
bytes_data = message.get("bytes")
text_data = message.get("text")
data = text_data if bytes_data is None else bytes_data
output = self.conn.send(wsproto.events.Message(data=data))
if not self.transport.is_closing():
self.transport.write(output)
elif message_type == "websocket.close":
self.close_sent = True
code = message.get("code", 1000)
reason = message.get("reason", "") or ""
self.queue.put_nowait({"type": "websocket.disconnect", "code": code})
output = self.conn.send(
wsproto.events.CloseConnection(code=code, reason=reason)
)
if not self.transport.is_closing():
self.transport.write(output)
self.transport.close()
else:
msg = (
"Expected ASGI message 'websocket.send' or 'websocket.close',"
" but got '%s'."
)
raise RuntimeError(msg % message_type)
else:
msg = "Unexpected ASGI message '%s', after sending 'websocket.close'."
raise RuntimeError(msg % message_type)
async def receive(self):
message = await self.queue.get()
if self.read_paused and self.queue.empty():
self.read_paused = False
self.transport.resume_reading()
return message