summaryrefslogtreecommitdiffstats
path: root/Lib/asyncio/subprocess.py
blob: c9506b158302b5e8027a636fdb7c9ca9c965b938 (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
__all__ = 'create_subprocess_exec', 'create_subprocess_shell'

import subprocess
import warnings

from . import events
from . import protocols
from . import streams
from . import tasks
from .log import logger


PIPE = subprocess.PIPE
STDOUT = subprocess.STDOUT
DEVNULL = subprocess.DEVNULL


class SubprocessStreamProtocol(streams.FlowControlMixin,
                               protocols.SubprocessProtocol):
    """Like StreamReaderProtocol, but for a subprocess."""

    def __init__(self, limit, loop):
        super().__init__(loop=loop)
        self._limit = limit
        self.stdin = self.stdout = self.stderr = None
        self._transport = None
        self._process_exited = False
        self._pipe_fds = []
        self._stdin_closed = self._loop.create_future()

    def __repr__(self):
        info = [self.__class__.__name__]
        if self.stdin is not None:
            info.append(f'stdin={self.stdin!r}')
        if self.stdout is not None:
            info.append(f'stdout={self.stdout!r}')
        if self.stderr is not None:
            info.append(f'stderr={self.stderr!r}')
        return '<{}>'.format(' '.join(info))

    def connection_made(self, transport):
        self._transport = transport

        stdout_transport = transport.get_pipe_transport(1)
        if stdout_transport is not None:
            self.stdout = streams.StreamReader(limit=self._limit,
                                               loop=self._loop)
            self.stdout.set_transport(stdout_transport)
            self._pipe_fds.append(1)

        stderr_transport = transport.get_pipe_transport(2)
        if stderr_transport is not None:
            self.stderr = streams.StreamReader(limit=self._limit,
                                               loop=self._loop)
            self.stderr.set_transport(stderr_transport)
            self._pipe_fds.append(2)

        stdin_transport = transport.get_pipe_transport(0)
        if stdin_transport is not None:
            self.stdin = streams.StreamWriter(stdin_transport,
                                              protocol=self,
                                              reader=None,
                                              loop=self._loop)

    def pipe_data_received(self, fd, data):
        if fd == 1:
            reader = self.stdout
        elif fd == 2:
            reader = self.stderr
        else:
            reader = None
        if reader is not None:
            reader.feed_data(data)

    def pipe_connection_lost(self, fd, exc):
        if fd == 0:
            pipe = self.stdin
            if pipe is not None:
                pipe.close()
            self.connection_lost(exc)
            if exc is None:
                self._stdin_closed.set_result(None)
            else:
                self._stdin_closed.set_exception(exc)
            return
        if fd == 1:
            reader = self.stdout
        elif fd == 2:
            reader = self.stderr
        else:
            reader = None
        if reader is not None:
            if exc is None:
                reader.feed_eof()
            else:
                reader.set_exception(exc)

        if fd in self._pipe_fds:
            self._pipe_fds.remove(fd)
        self._maybe_close_transport()

    def process_exited(self):
        self._process_exited = True
        self._maybe_close_transport()

    def _maybe_close_transport(self):
        if len(self._pipe_fds) == 0 and self._process_exited:
            self._transport.close()
            self._transport = None

    def _get_close_waiter(self, stream):
        if stream is self.stdin:
            return self._stdin_closed


class Process:
    def __init__(self, transport, protocol, loop):
        self._transport = transport
        self._protocol = protocol
        self._loop = loop
        self.stdin = protocol.stdin
        self.stdout = protocol.stdout
        self.stderr = protocol.stderr
        self.pid = transport.get_pid()

    def __repr__(self):
        return f'<{self.__class__.__name__} {self.pid}>'

    @property
    def returncode(self):
        return self._transport.get_returncode()

    async def wait(self):
        """Wait until the process exit and return the process return code."""
        return await self._transport._wait()

    def send_signal(self, signal):
        self._transport.send_signal(signal)

    def terminate(self):
        self._transport.terminate()

    def kill(self):
        self._transport.kill()

    async def _feed_stdin(self, input):
        debug = self._loop.get_debug()
        self.stdin.write(input)
        if debug:
            logger.debug(
                '%r communicate: feed stdin (%s bytes)', self, len(input))
        try:
            await self.stdin.drain()
        except (BrokenPipeError, ConnectionResetError) as exc:
            # communicate() ignores BrokenPipeError and ConnectionResetError
            if debug:
                logger.debug('%r communicate: stdin got %r', self, exc)

        if debug:
            logger.debug('%r communicate: close stdin', self)
        self.stdin.close()

    async def _noop(self):
        return None

    async def _read_stream(self, fd):
        transport = self._transport.get_pipe_transport(fd)
        if fd == 2:
            stream = self.stderr
        else:
            assert fd == 1
            stream = self.stdout
        if self._loop.get_debug():
            name = 'stdout' if fd == 1 else 'stderr'
            logger.debug('%r communicate: read %s', self, name)
        output = await stream.read()
        if self._loop.get_debug():
            name = 'stdout' if fd == 1 else 'stderr'
            logger.debug('%r communicate: close %s', self, name)
        transport.close()
        return output

    async def communicate(self, input=None):
        if input is not None:
            stdin = self._feed_stdin(input)
        else:
            stdin = self._noop()
        if self.stdout is not None:
            stdout = self._read_stream(1)
        else:
            stdout = self._noop()
        if self.stderr is not None:
            stderr = self._read_stream(2)
        else:
            stderr = self._noop()
        stdin, stdout, stderr = await tasks.gather(stdin, stdout, stderr,
                                                   loop=self._loop)
        await self.wait()
        return (stdout, stderr)


async def create_subprocess_shell(cmd, stdin=None, stdout=None, stderr=None,
                                  loop=None, limit=streams._DEFAULT_LIMIT,
                                  **kwds):
    if loop is None:
        loop = events.get_event_loop()
    else:
        warnings.warn("The loop argument is deprecated since Python 3.8 "
                      "and scheduled for removal in Python 3.10.",
                      DeprecationWarning,
                      stacklevel=2
        )

    protocol_factory = lambda: SubprocessStreamProtocol(limit=limit,
                                                        loop=loop)
    transport, protocol = await loop.subprocess_shell(
        protocol_factory,
        cmd, stdin=stdin, stdout=stdout,
        stderr=stderr, **kwds)
    return Process(transport, protocol, loop)


async def create_subprocess_exec(program, *args, stdin=None, stdout=None,
                                 stderr=None, loop=None,
                                 limit=streams._DEFAULT_LIMIT, **kwds):
    if loop is None:
        loop = events.get_event_loop()
    else:
        warnings.warn("The loop argument is deprecated since Python 3.8 "
                      "and scheduled for removal in Python 3.10.",
                      DeprecationWarning,
                      stacklevel=2
        )
    protocol_factory = lambda: SubprocessStreamProtocol(limit=limit,
                                                        loop=loop)
    transport, protocol = await loop.subprocess_exec(
        protocol_factory,
        program, *args,
        stdin=stdin, stdout=stdout,
        stderr=stderr, **kwds)
    return Process(transport, protocol, loop)