1
|
|
|
""" |
2
|
|
|
weitersager.http |
3
|
|
|
~~~~~~~~~~~~~~~~ |
4
|
|
|
|
5
|
|
|
HTTP server to receive messages |
6
|
|
|
|
7
|
|
|
:Copyright: 2007-2022 Jochen Kupperschmidt |
8
|
|
|
:License: MIT, see LICENSE for details. |
9
|
|
|
""" |
10
|
|
|
|
11
|
1 |
|
from __future__ import annotations |
12
|
1 |
|
from dataclasses import dataclass |
13
|
1 |
|
from http import HTTPStatus |
14
|
1 |
|
import logging |
15
|
1 |
|
import sys |
16
|
1 |
|
from typing import Optional |
17
|
1 |
|
from wsgiref.simple_server import make_server, ServerHandler, WSGIServer |
18
|
|
|
|
19
|
1 |
|
from werkzeug.exceptions import abort, HTTPException |
20
|
1 |
|
from werkzeug.routing import Map, Rule |
21
|
1 |
|
from werkzeug.wrappers import Request, Response |
22
|
|
|
|
23
|
1 |
|
from .config import HttpConfig |
24
|
1 |
|
from .signals import message_received |
25
|
1 |
|
from .util import start_thread |
26
|
|
|
|
27
|
|
|
|
28
|
1 |
|
logger = logging.getLogger(__name__) |
29
|
|
|
|
30
|
|
|
|
31
|
1 |
|
@dataclass(frozen=True) |
32
|
|
|
class Message: |
33
|
1 |
|
channel: str |
34
|
1 |
|
text: str |
35
|
|
|
|
36
|
|
|
|
37
|
1 |
|
def create_app(api_tokens: set[str]): |
38
|
1 |
|
return Application(api_tokens) |
39
|
|
|
|
40
|
|
|
|
41
|
1 |
|
class Application: |
42
|
1 |
|
def __init__(self, api_tokens: set[str]): |
43
|
1 |
|
self._api_tokens = api_tokens |
44
|
|
|
|
45
|
1 |
|
self._url_map = Map( |
46
|
|
|
[ |
47
|
|
|
Rule('/', endpoint='root'), |
48
|
|
|
] |
49
|
|
|
) |
50
|
|
|
|
51
|
1 |
|
def __call__(self, environ, start_response): |
52
|
1 |
|
return self.wsgi_app(environ, start_response) |
53
|
|
|
|
54
|
1 |
|
@Request.application |
55
|
|
|
def wsgi_app(self, request): |
56
|
1 |
|
adapter = self._url_map.bind_to_environ(request.environ) |
57
|
1 |
|
try: |
58
|
1 |
|
endpoint, values = adapter.match() |
59
|
1 |
|
handler = getattr(self, f'on_{endpoint}') |
60
|
1 |
|
return handler(request, **values) |
61
|
1 |
|
except HTTPException as exc: |
62
|
1 |
|
return exc |
63
|
|
|
|
64
|
1 |
|
def on_root(self, request): |
65
|
1 |
|
if self._api_tokens: |
66
|
1 |
|
api_token = _get_api_token(request.headers) |
67
|
1 |
|
if not api_token: |
68
|
1 |
|
abort(HTTPStatus.UNAUTHORIZED) |
69
|
|
|
|
70
|
1 |
|
if api_token not in self._api_tokens: |
71
|
1 |
|
abort(HTTPStatus.FORBIDDEN) |
72
|
|
|
|
73
|
1 |
|
if not request.is_json: |
74
|
|
|
abort(HTTPStatus.UNSUPPORTED_MEDIA_TYPE) |
75
|
|
|
|
76
|
1 |
|
try: |
77
|
1 |
|
message = _parse_json_message(request.json) |
78
|
1 |
|
except (KeyError, ValueError): |
79
|
1 |
|
logger.info( |
80
|
|
|
'Invalid message received from %s.', request.remote_addr |
81
|
|
|
) |
82
|
1 |
|
abort(HTTPStatus.BAD_REQUEST) |
83
|
|
|
|
84
|
1 |
|
message_received.send( |
85
|
|
|
channel_name=message.channel, |
86
|
|
|
text=message.text, |
87
|
|
|
source_ip_address=request.remote_addr, |
88
|
|
|
) |
89
|
|
|
|
90
|
1 |
|
return Response('', status=HTTPStatus.ACCEPTED) |
91
|
|
|
|
92
|
|
|
|
93
|
1 |
|
def _get_api_token(headers) -> Optional[str]: |
94
|
1 |
|
authorization_value = headers.get('Authorization') |
95
|
1 |
|
if not authorization_value: |
96
|
1 |
|
return None |
97
|
|
|
|
98
|
1 |
|
prefix = 'Token ' |
99
|
1 |
|
if not authorization_value.startswith(prefix): |
100
|
|
|
return None |
101
|
|
|
|
102
|
1 |
|
return authorization_value[len(prefix) :] |
103
|
|
|
|
104
|
|
|
|
105
|
1 |
|
def _parse_json_message(data: dict[str, str]) -> Message: |
106
|
|
|
"""Extract message from JSON.""" |
107
|
1 |
|
channel = data['channel'] |
108
|
1 |
|
text = data['text'] |
109
|
|
|
|
110
|
1 |
|
return Message(channel=channel, text=text) |
111
|
|
|
|
112
|
|
|
|
113
|
|
|
# Override value of `Server:` header sent by wsgiref. |
114
|
1 |
|
ServerHandler.server_software = 'Weitersager' |
115
|
|
|
|
116
|
|
|
|
117
|
1 |
|
def create_server(config: HttpConfig) -> WSGIServer: |
118
|
|
|
"""Create the HTTP server.""" |
119
|
1 |
|
app = create_app(config.api_tokens) |
120
|
|
|
|
121
|
1 |
|
return make_server(config.host, config.port, app) |
122
|
|
|
|
123
|
|
|
|
124
|
1 |
|
def start_receive_server(config: HttpConfig) -> None: |
125
|
|
|
"""Start in a separate thread.""" |
126
|
|
|
try: |
127
|
|
|
server = create_server(config) |
128
|
|
|
except OSError as e: |
129
|
|
|
sys.stderr.write(f'Error {e.errno:d}: {e.strerror}\n') |
130
|
|
|
sys.stderr.write( |
131
|
|
|
f'Probably no permission to open port {config.port}. ' |
132
|
|
|
'Try to specify a port number above 1,024 (or even ' |
133
|
|
|
'4,096) and up to 65,535.\n' |
134
|
|
|
) |
135
|
|
|
sys.exit(1) |
136
|
|
|
|
137
|
|
|
thread_name = server.__class__.__name__ |
138
|
|
|
start_thread(server.serve_forever, thread_name) |
139
|
|
|
logger.info('Listening for HTTP requests on %s:%d.', *server.server_address) |
140
|
|
|
|