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 http import HTTPStatus |
13
|
1 |
|
import logging |
14
|
1 |
|
import sys |
15
|
1 |
|
from typing import Optional |
16
|
1 |
|
from wsgiref.simple_server import make_server, ServerHandler, WSGIServer |
17
|
|
|
|
18
|
1 |
|
from werkzeug.datastructures import Headers |
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 |
|
def create_app( |
32
|
|
|
api_tokens: set[str], channel_tokens_to_channel_names: dict[str, str] |
33
|
|
|
) -> Application: |
34
|
1 |
|
return Application(api_tokens, channel_tokens_to_channel_names) |
35
|
|
|
|
36
|
|
|
|
37
|
1 |
|
class Application: |
38
|
1 |
|
def __init__( |
39
|
|
|
self, |
40
|
|
|
api_tokens: set[str], |
41
|
|
|
channel_tokens_to_channel_names: dict[str, str], |
42
|
|
|
) -> None: |
43
|
1 |
|
self._api_tokens = api_tokens |
44
|
1 |
|
self._channel_tokens_to_channel_names = channel_tokens_to_channel_names |
45
|
|
|
|
46
|
1 |
|
self._url_map = Map( |
47
|
|
|
[ |
48
|
|
|
Rule('/', endpoint='root'), |
49
|
|
|
Rule('/ct/<channel_token>', endpoint='channel_token'), |
50
|
|
|
] |
51
|
|
|
) |
52
|
|
|
|
53
|
1 |
|
def __call__(self, environ, start_response): |
54
|
1 |
|
return self.wsgi_app(environ, start_response) |
55
|
|
|
|
56
|
1 |
|
def wsgi_app(self, environ, start_response): |
57
|
1 |
|
request = Request(environ) |
58
|
1 |
|
response = self.dispatch_request(request) |
59
|
1 |
|
return response(environ, start_response) |
60
|
|
|
|
61
|
1 |
|
def dispatch_request(self, request: Request): |
62
|
1 |
|
adapter = self._url_map.bind_to_environ(request.environ) |
63
|
|
|
|
64
|
1 |
|
try: |
65
|
1 |
|
endpoint, values = adapter.match() |
66
|
1 |
|
handler = getattr(self, f'on_{endpoint}') |
67
|
1 |
|
return handler(request, **values) |
68
|
1 |
|
except HTTPException as exc: |
69
|
1 |
|
return exc |
70
|
|
|
|
71
|
1 |
|
def on_root(self, request: Request) -> Response: |
72
|
1 |
|
if self._api_tokens: |
73
|
1 |
|
api_token = _get_api_token(request.headers) |
74
|
1 |
|
if not api_token: |
75
|
1 |
|
abort(HTTPStatus.UNAUTHORIZED) |
76
|
|
|
|
77
|
1 |
|
if api_token not in self._api_tokens: |
78
|
1 |
|
abort(HTTPStatus.FORBIDDEN) |
79
|
|
|
|
80
|
1 |
|
data = _extract_payload(request, {'channel', 'text'}) |
81
|
|
|
|
82
|
1 |
|
message_received.send( |
83
|
|
|
channel_name=data['channel'], |
84
|
|
|
text=data['text'], |
85
|
|
|
source_ip_address=request.remote_addr, |
86
|
|
|
) |
87
|
|
|
|
88
|
1 |
|
return Response('', status=HTTPStatus.ACCEPTED) |
89
|
|
|
|
90
|
1 |
|
def on_channel_token( |
91
|
|
|
self, request: Request, channel_token: str |
92
|
|
|
) -> Response: |
93
|
|
|
channel_name = self._channel_tokens_to_channel_names.get(channel_token) |
94
|
|
|
if channel_name is None: |
95
|
|
|
abort(HTTPStatus.NOT_FOUND) |
96
|
|
|
|
97
|
|
|
data = _extract_payload(request, {'text'}) |
98
|
|
|
|
99
|
|
|
message_received.send( |
100
|
|
|
channel_name=channel_name, |
101
|
|
|
text=data['text'], |
102
|
|
|
source_ip_address=request.remote_addr, |
103
|
|
|
) |
104
|
|
|
|
105
|
|
|
return Response('', status=HTTPStatus.ACCEPTED) |
106
|
|
|
|
107
|
|
|
|
108
|
1 |
|
def _get_api_token(headers: Headers) -> Optional[str]: |
109
|
1 |
|
authorization_value = headers.get('Authorization') |
110
|
1 |
|
if not authorization_value: |
111
|
1 |
|
return None |
112
|
|
|
|
113
|
1 |
|
prefix = 'Token ' |
114
|
1 |
|
if not authorization_value.startswith(prefix): |
115
|
|
|
return None |
116
|
|
|
|
117
|
1 |
|
return authorization_value[len(prefix) :] |
118
|
|
|
|
119
|
|
|
|
120
|
1 |
|
def _extract_payload(request: Request, keys: set[str]) -> dict[str, str]: |
121
|
|
|
"""Extract values for given keys from JSON payload.""" |
122
|
1 |
|
if not request.is_json: |
123
|
|
|
abort(HTTPStatus.UNSUPPORTED_MEDIA_TYPE) |
124
|
|
|
|
125
|
1 |
|
payload = request.json |
126
|
1 |
|
if payload is None: |
127
|
|
|
abort(HTTPStatus.BAD_REQUEST) |
128
|
|
|
|
129
|
1 |
|
data = {} |
130
|
1 |
|
try: |
131
|
1 |
|
for key in keys: |
132
|
1 |
|
data[key] = payload[key] |
133
|
1 |
|
except KeyError: |
134
|
1 |
|
abort(HTTPStatus.BAD_REQUEST) |
135
|
|
|
|
136
|
1 |
|
return data |
137
|
|
|
|
138
|
|
|
|
139
|
|
|
# Override value of `Server:` header sent by wsgiref. |
140
|
1 |
|
ServerHandler.server_software = 'Weitersager' |
141
|
|
|
|
142
|
|
|
|
143
|
1 |
|
def create_server(config: HttpConfig) -> WSGIServer: |
144
|
|
|
"""Create the HTTP server.""" |
145
|
1 |
|
app = create_app(config.api_tokens, config.channel_tokens_to_channel_names) |
146
|
|
|
|
147
|
1 |
|
return make_server(config.host, config.port, app) |
148
|
|
|
|
149
|
|
|
|
150
|
1 |
|
def start_receive_server(config: HttpConfig) -> None: |
151
|
|
|
"""Start in a separate thread.""" |
152
|
|
|
try: |
153
|
|
|
server = create_server(config) |
154
|
|
|
except OSError as e: |
155
|
|
|
sys.stderr.write(f'Error {e.errno:d}: {e.strerror}\n') |
156
|
|
|
sys.stderr.write( |
157
|
|
|
f'Probably no permission to open port {config.port}. ' |
158
|
|
|
'Try to specify a port number above 1,024 (or even ' |
159
|
|
|
'4,096) and up to 65,535.\n' |
160
|
|
|
) |
161
|
|
|
sys.exit(1) |
162
|
|
|
|
163
|
|
|
thread_name = server.__class__.__name__ |
164
|
|
|
start_thread(server.serve_forever, thread_name) |
165
|
|
|
logger.info('Listening for HTTP requests on %s:%d.', *server.server_address) |
166
|
|
|
|