aboutsummaryrefslogtreecommitdiff
path: root/.venv/lib/python3.12/site-packages/uvicorn/protocols/websockets/wsproto_impl.py
blob: 85880a408d560190a2ec5fcc50e324c4d287e605 (about) (plain)
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
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
from __future__ import annotations

import asyncio
import logging
import typing
from typing import Literal
from urllib.parse import unquote

import wsproto
from wsproto import ConnectionType, events
from wsproto.connection import ConnectionState
from wsproto.extensions import Extension, PerMessageDeflate
from wsproto.utilities import LocalProtocolError, RemoteProtocolError

from uvicorn._types import (
    ASGISendEvent,
    WebSocketAcceptEvent,
    WebSocketCloseEvent,
    WebSocketEvent,
    WebSocketResponseBodyEvent,
    WebSocketResponseStartEvent,
    WebSocketScope,
    WebSocketSendEvent,
)
from uvicorn.config import Config
from uvicorn.logging import TRACE_LOG_LEVEL
from uvicorn.protocols.utils import (
    ClientDisconnected,
    get_local_addr,
    get_path_with_query_string,
    get_remote_addr,
    is_ssl,
)
from uvicorn.server import ServerState


class WSProtocol(asyncio.Protocol):
    def __init__(
        self,
        config: Config,
        server_state: ServerState,
        app_state: dict[str, typing.Any],
        _loop: asyncio.AbstractEventLoop | None = None,
    ) -> 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
        self.app_state = app_state

        # Shared server state
        self.connections = server_state.connections
        self.tasks = server_state.tasks
        self.default_headers = server_state.default_headers

        # Connection state
        self.transport: asyncio.Transport = None  # type: ignore[assignment]
        self.server: tuple[str, int] | None = None
        self.client: tuple[str, int] | None = None
        self.scheme: Literal["wss", "ws"] = None  # type: ignore[assignment]

        # WebSocket state
        self.queue: asyncio.Queue[WebSocketEvent] = asyncio.Queue()
        self.handshake_complete = False
        self.close_sent = False

        # Rejection state
        self.response_started = 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(  # type: ignore[override]
        self, transport: asyncio.Transport
    ) -> None:
        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 - " % self.client if self.client else ""
            self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection made", prefix)

    def connection_lost(self, exc: Exception | None) -> None:
        code = 1005 if self.handshake_complete else 1006
        self.queue.put_nowait({"type": "websocket.disconnect", "code": code})
        self.connections.remove(self)

        if self.logger.level <= TRACE_LOG_LEVEL:
            prefix = "%s:%d - " % self.client if self.client else ""
            self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection lost", prefix)

        self.handshake_complete = True
        if exc is None:
            self.transport.close()

    def eof_received(self) -> None:
        pass

    def data_received(self, data: bytes) -> None:
        try:
            self.conn.receive_data(data)
        except RemoteProtocolError as err:
            # TODO: Remove `type: ignore` when wsproto fixes the type annotation.
            self.transport.write(self.conn.send(err.event_hint))  # type: ignore[arg-type]  # noqa: E501
            self.transport.close()
        else:
            self.handle_events()

    def handle_events(self) -> None:
        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.CloseConnection):
                self.handle_close(event)
            elif isinstance(event, events.Ping):
                self.handle_ping(event)

    def pause_writing(self) -> None:
        """
        Called by the transport when the write buffer exceeds the high water mark.
        """
        self.writable.clear()

    def resume_writing(self) -> None:
        """
        Called by the transport when the write buffer drops below the low water mark.
        """
        self.writable.set()

    def shutdown(self) -> None:
        if self.handshake_complete:
            self.queue.put_nowait({"type": "websocket.disconnect", "code": 1012})
            output = self.conn.send(wsproto.events.CloseConnection(code=1012))
            self.transport.write(output)
        else:
            self.send_500_response()
        self.transport.close()

    def on_task_complete(self, task: asyncio.Task) -> None:
        self.tasks.discard(task)

    # Event handlers

    def handle_connect(self, event: events.Request) -> None:
        headers = [(b"host", event.host.encode())]
        headers += [(key.lower(), value) for key, value in event.extra_headers]
        raw_path, _, query_string = event.target.partition("?")
        path = unquote(raw_path)
        full_path = self.root_path + path
        full_raw_path = self.root_path.encode("ascii") + raw_path.encode("ascii")
        self.scope: "WebSocketScope" = {
            "type": "websocket",
            "asgi": {"version": self.config.asgi_version, "spec_version": "2.4"},
            "http_version": "1.1",
            "scheme": self.scheme,
            "server": self.server,
            "client": self.client,
            "root_path": self.root_path,
            "path": full_path,
            "raw_path": full_raw_path,
            "query_string": query_string.encode("ascii"),
            "headers": headers,
            "subprotocols": event.subprotocols,
            "state": self.app_state.copy(),
            "extensions": {"websocket.http.response": {}},
        }
        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_text(self, event: events.TextMessage) -> None:
        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: events.BytesMessage) -> None:
        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: events.CloseConnection) -> None:
        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: events.Ping) -> None:
        self.transport.write(self.conn.send(event.response()))

    def send_500_response(self) -> None:
        if self.response_started or self.handshake_complete:
            return  # we cannot send responses anymore
        headers = [
            (b"content-type", b"text/plain; charset=utf-8"),
            (b"connection", b"close"),
        ]
        output = self.conn.send(
            wsproto.events.RejectConnection(
                status_code=500, headers=headers, has_body=True
            )
        )
        output += self.conn.send(
            wsproto.events.RejectData(data=b"Internal Server Error")
        )
        self.transport.write(output)

    async def run_asgi(self) -> None:
        try:
            result = await self.app(self.scope, self.receive, self.send)
        except ClientDisconnected:
            self.transport.close()
        except BaseException:
            self.logger.exception("Exception in ASGI application\n")
            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: ASGISendEvent) -> None:
        await self.writable.wait()

        message_type = message["type"]

        if not self.handshake_complete:
            if message_type == "websocket.accept":
                message = typing.cast(WebSocketAcceptEvent, message)
                self.logger.info(
                    '%s - "WebSocket %s" [accepted]',
                    self.scope["client"],
                    get_path_with_query_string(self.scope),
                )
                subprotocol = message.get("subprotocol")
                extra_headers = self.default_headers + list(message.get("headers", []))
                extensions: typing.List[Extension] = []
                if self.config.ws_per_message_deflate:
                    extensions.append(PerMessageDeflate())
                if not self.transport.is_closing():
                    self.handshake_complete = True
                    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": 1006})
                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
                event = events.RejectConnection(status_code=403, headers=[])
                output = self.conn.send(event)
                self.transport.write(output)
                self.transport.close()

            elif message_type == "websocket.http.response.start":
                message = typing.cast(WebSocketResponseStartEvent, message)
                # ensure status code is in the valid range
                if not (100 <= message["status"] < 600):
                    msg = "Invalid HTTP status code '%d' in response."
                    raise RuntimeError(msg % message["status"])
                self.logger.info(
                    '%s - "WebSocket %s" %d',
                    self.scope["client"],
                    get_path_with_query_string(self.scope),
                    message["status"],
                )
                self.handshake_complete = True
                event = events.RejectConnection(
                    status_code=message["status"],
                    headers=list(message["headers"]),
                    has_body=True,
                )
                output = self.conn.send(event)
                self.transport.write(output)
                self.response_started = True

            else:
                msg = (
                    "Expected ASGI message 'websocket.accept', 'websocket.close' "
                    "or 'websocket.http.response.start' "
                    "but got '%s'."
                )
                raise RuntimeError(msg % message_type)

        elif not self.close_sent and not self.response_started:
            try:
                if message_type == "websocket.send":
                    message = typing.cast(WebSocketSendEvent, message)
                    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))  # type: ignore
                    if not self.transport.is_closing():
                        self.transport.write(output)

                elif message_type == "websocket.close":
                    message = typing.cast(WebSocketCloseEvent, message)
                    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)
            except LocalProtocolError as exc:
                raise ClientDisconnected from exc
        elif self.response_started:
            if message_type == "websocket.http.response.body":
                message = typing.cast("WebSocketResponseBodyEvent", message)
                body_finished = not message.get("more_body", False)
                reject_data = events.RejectData(
                    data=message["body"], body_finished=body_finished
                )
                output = self.conn.send(reject_data)
                self.transport.write(output)

                if body_finished:
                    self.queue.put_nowait(
                        {"type": "websocket.disconnect", "code": 1006}
                    )
                    self.close_sent = True
                    self.transport.close()

            else:
                msg = (
                    "Expected ASGI message 'websocket.http.response.body' "
                    "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) -> WebSocketEvent:
        message = await self.queue.get()
        if self.read_paused and self.queue.empty():
            self.read_paused = False
            self.transport.resume_reading()
        return message