File: tcp_server.py

package info (click to toggle)
python-bumble 0.0.225-1
  • links: PTS, VCS
  • area: main
  • in suites:
  • size: 9,464 kB
  • sloc: python: 75,258; java: 3,782; javascript: 823; xml: 203; sh: 172; makefile: 8
file content (106 lines) | stat: -rw-r--r-- 3,755 bytes parent folder | download | duplicates (3)
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
# Copyright 2021-2022 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# -----------------------------------------------------------------------------
# Imports
# -----------------------------------------------------------------------------
from __future__ import annotations

import asyncio
import logging
import socket

from bumble.transport.common import StreamPacketSource, Transport

# -----------------------------------------------------------------------------
# Logging
# -----------------------------------------------------------------------------
logger = logging.getLogger(__name__)


# -----------------------------------------------------------------------------
async def open_tcp_server_transport(spec: str) -> Transport:
    '''
    Open a TCP server transport.
    The parameter string has this syntax:
    <local-host>:<local-port>
    Where <local-host> may be the address of a local network interface, or '_'
    to accept connections on all local network interfaces.

    Example: _:9001
    '''
    local_host, local_port = spec.rsplit(':', maxsplit=1)
    return await _open_tcp_server_transport_impl(
        host=local_host if local_host != '_' else None, port=int(local_port)
    )


async def open_tcp_server_transport_with_socket(
    sock: socket.socket,
) -> Transport:
    '''
    Open a TCP server transport with an existing socket.

    One reason to use this variant is to let python pick an unused port.
    '''
    return await _open_tcp_server_transport_impl(sock=sock)


async def _open_tcp_server_transport_impl(**kwargs) -> Transport:
    class TcpServerTransport(Transport):
        def __init__(self, source, sink, server):
            self.server = server
            super().__init__(source, sink)

    class TcpServerProtocol(asyncio.BaseProtocol):
        def __init__(self, packet_source, packet_sink):
            self.packet_source = packet_source
            self.packet_sink = packet_sink

        # Called when a new connection is established
        def connection_made(self, transport):
            peer_name = transport.get_extra_info('peer_name')
            logger.debug(f'connection from {peer_name}')
            self.packet_sink.transport = transport

        # Called when the client is disconnected
        def connection_lost(self, error):
            logger.debug(f'connection lost: {error}')
            self.packet_sink.transport = None

        def eof_received(self):
            logger.debug('connection end')
            self.packet_sink.transport = None

        # Called when data is received on the socket
        def data_received(self, data):
            self.packet_source.data_received(data)

    class TcpServerPacketSink:
        def __init__(self):
            self.transport = None

        def on_packet(self, packet):
            if self.transport:
                self.transport.write(packet)
            else:
                logger.debug('no client, dropping packet')

    packet_source = StreamPacketSource()
    packet_sink = TcpServerPacketSink()
    server = await asyncio.get_running_loop().create_server(
        lambda: TcpServerProtocol(packet_source, packet_sink), **kwargs
    )

    return TcpServerTransport(packet_source, packet_sink, server)