|
1
|
|
|
"""Event loop implementation that uses the `asyncio` standard module. |
|
2
|
|
|
|
|
3
|
|
|
The `asyncio` module was added to python standard library on 3.4, and it |
|
4
|
|
|
provides a pure python implementation of an event loop library. It is used |
|
5
|
|
|
as a fallback in case pyuv is not available(on python implementations other |
|
6
|
|
|
than CPython). |
|
7
|
|
|
|
|
8
|
|
|
Earlier python versions are supported through the `trollius` package, which |
|
9
|
|
|
is a backport of `asyncio` that works on Python 2.6+. |
|
10
|
|
|
""" |
|
11
|
6 |
|
from __future__ import absolute_import |
|
12
|
|
|
|
|
13
|
6 |
|
import logging |
|
14
|
6 |
|
import os |
|
15
|
6 |
|
import sys |
|
16
|
6 |
|
from collections import deque |
|
17
|
|
|
|
|
18
|
6 |
|
try: |
|
19
|
|
|
# For python 3.4+, use the standard library module |
|
20
|
6 |
|
import asyncio |
|
21
|
2 |
|
except (ImportError, SyntaxError): |
|
22
|
|
|
# Fallback to trollius |
|
23
|
2 |
|
import trollius as asyncio |
|
24
|
|
|
|
|
25
|
6 |
|
from .base import BaseEventLoop |
|
26
|
|
|
|
|
27
|
6 |
|
logger = logging.getLogger(__name__) |
|
28
|
6 |
|
debug, info, warn = (logger.debug, logger.info, logger.warning,) |
|
29
|
|
|
|
|
30
|
6 |
|
loop_cls = asyncio.SelectorEventLoop |
|
31
|
6 |
|
if os.name == 'nt': |
|
32
|
|
|
from asyncio.windows_utils import PipeHandle |
|
33
|
6 |
|
import msvcrt |
|
34
|
|
|
|
|
35
|
|
|
# On windows use ProactorEventLoop which support pipes and is backed by the |
|
36
|
|
|
# more powerful IOCP facility |
|
37
|
|
|
# NOTE: we override in the stdio case, because it doesn't work. |
|
38
|
|
|
loop_cls = asyncio.ProactorEventLoop |
|
39
|
|
|
|
|
40
|
|
|
|
|
41
|
6 |
|
class AsyncioEventLoop(BaseEventLoop, asyncio.Protocol, |
|
42
|
|
|
asyncio.SubprocessProtocol): |
|
43
|
|
|
|
|
44
|
|
|
"""`BaseEventLoop` subclass that uses `asyncio` as a backend.""" |
|
45
|
|
|
|
|
46
|
6 |
|
def connection_made(self, transport): |
|
47
|
|
|
"""Used to signal `asyncio.Protocol` of a successful connection.""" |
|
48
|
6 |
|
self._transport = transport |
|
49
|
6 |
|
self._raw_transport = transport |
|
50
|
6 |
|
if isinstance(transport, asyncio.SubprocessTransport): |
|
51
|
6 |
|
self._transport = transport.get_pipe_transport(0) |
|
52
|
|
|
|
|
53
|
6 |
|
def connection_lost(self, exc): |
|
54
|
|
|
"""Used to signal `asyncio.Protocol` of a lost connection.""" |
|
55
|
|
|
self._on_error(exc.args[0] if exc else 'EOF') |
|
56
|
|
|
|
|
57
|
6 |
|
def data_received(self, data): |
|
58
|
|
|
"""Used to signal `asyncio.Protocol` of incoming data.""" |
|
59
|
|
|
if self._on_data: |
|
60
|
|
|
self._on_data(data) |
|
61
|
4 |
|
return |
|
62
|
4 |
|
self._queued_data.append(data) |
|
63
|
|
|
|
|
64
|
6 |
|
def pipe_connection_lost(self, fd, exc): |
|
65
|
|
|
"""Used to signal `asyncio.SubprocessProtocol` of a lost connection.""" |
|
66
|
6 |
|
self._on_error(exc.args[0] if exc else 'EOF') |
|
67
|
|
|
|
|
68
|
6 |
|
def pipe_data_received(self, fd, data): |
|
69
|
|
|
"""Used to signal `asyncio.SubprocessProtocol` of incoming data.""" |
|
70
|
6 |
|
if fd == 2: # stderr fd number |
|
71
|
|
|
self._on_stderr(data) |
|
72
|
6 |
|
elif self._on_data: |
|
73
|
6 |
|
self._on_data(data) |
|
74
|
|
|
else: |
|
75
|
|
|
self._queued_data.append(data) |
|
76
|
|
|
|
|
77
|
6 |
|
def process_exited(self): |
|
78
|
|
|
"""Used to signal `asyncio.SubprocessProtocol` when the child exits.""" |
|
79
|
|
|
self._on_error('EOF') |
|
80
|
|
|
|
|
81
|
6 |
|
def _init(self): |
|
82
|
6 |
|
self._loop = loop_cls() |
|
83
|
6 |
|
self._queued_data = deque() |
|
84
|
6 |
|
self._fact = lambda: self |
|
85
|
6 |
|
self._raw_transport = None |
|
86
|
|
|
|
|
87
|
6 |
|
def _connect_tcp(self, address, port): |
|
88
|
|
|
coroutine = self._loop.create_connection(self._fact, address, port) |
|
89
|
|
|
self._loop.run_until_complete(coroutine) |
|
90
|
|
|
|
|
91
|
6 |
|
def _connect_socket(self, path): |
|
92
|
|
|
if os.name == 'nt': |
|
93
|
2 |
|
coroutine = self._loop.create_pipe_connection(self._fact, path) |
|
94
|
|
|
else: |
|
95
|
|
|
coroutine = self._loop.create_unix_connection(self._fact, path) |
|
96
|
|
|
self._loop.run_until_complete(coroutine) |
|
97
|
|
|
|
|
98
|
6 |
|
def _connect_stdio(self): |
|
99
|
|
|
if os.name == 'nt': |
|
100
|
|
|
pipe = PipeHandle(msvcrt.get_osfhandle(sys.stdin.fileno())) |
|
|
|
|
|
|
101
|
|
|
else: |
|
102
|
|
|
pipe = sys.stdin |
|
103
|
2 |
|
coroutine = self._loop.connect_read_pipe(self._fact, pipe) |
|
104
|
|
|
self._loop.run_until_complete(coroutine) |
|
105
|
2 |
|
debug("native stdin connection successful") |
|
106
|
|
|
|
|
107
|
|
|
# Make sure subprocesses don't clobber stdout, |
|
108
|
|
|
# send the output to stderr instead. |
|
109
|
2 |
|
rename_stdout = os.dup(sys.stdout.fileno()) |
|
110
|
2 |
|
os.dup2(sys.stderr.fileno(), sys.stdout.fileno()) |
|
111
|
|
|
|
|
112
|
|
|
if os.name == 'nt': |
|
113
|
|
|
pipe = PipeHandle(msvcrt.get_osfhandle(rename_stdout)) |
|
114
|
|
|
else: |
|
115
|
|
|
pipe = os.fdopen(rename_stdout, 'wb') |
|
116
|
|
|
coroutine = self._loop.connect_write_pipe(self._fact, pipe) |
|
117
|
|
|
self._loop.run_until_complete(coroutine) |
|
118
|
|
|
debug("native stdout connection successful") |
|
119
|
|
|
|
|
120
|
6 |
|
def _connect_child(self, argv): |
|
121
|
6 |
|
if os.name != 'nt': |
|
122
|
6 |
|
self._child_watcher = asyncio.get_child_watcher() |
|
123
|
6 |
|
self._child_watcher.attach_loop(self._loop) |
|
124
|
6 |
|
coroutine = self._loop.subprocess_exec(self._fact, *argv) |
|
125
|
6 |
|
self._loop.run_until_complete(coroutine) |
|
126
|
|
|
|
|
127
|
6 |
|
def _start_reading(self): |
|
128
|
6 |
|
pass |
|
129
|
|
|
|
|
130
|
6 |
|
def _send(self, data): |
|
131
|
6 |
|
self._transport.write(data) |
|
132
|
|
|
|
|
133
|
6 |
|
def _run(self): |
|
134
|
6 |
|
while self._queued_data: |
|
135
|
|
|
self._on_data(self._queued_data.popleft()) |
|
136
|
6 |
|
self._loop.run_forever() |
|
137
|
|
|
|
|
138
|
6 |
|
def _stop(self): |
|
139
|
6 |
|
self._loop.stop() |
|
140
|
|
|
|
|
141
|
6 |
|
def _close(self): |
|
142
|
|
|
if self._raw_transport is not None: |
|
143
|
|
|
self._raw_transport.close() |
|
144
|
|
|
self._loop.close() |
|
145
|
|
|
|
|
146
|
6 |
|
def _threadsafe_call(self, fn): |
|
147
|
6 |
|
self._loop.call_soon_threadsafe(fn) |
|
148
|
|
|
|
|
149
|
6 |
|
def _setup_signals(self, signals): |
|
150
|
6 |
|
if os.name == 'nt': |
|
151
|
|
|
# add_signal_handler is not supported in win32 |
|
152
|
|
|
self._signals = [] |
|
153
|
|
|
return |
|
154
|
|
|
|
|
155
|
6 |
|
self._signals = list(signals) |
|
156
|
6 |
|
for signum in self._signals: |
|
157
|
6 |
|
self._loop.add_signal_handler(signum, self._on_signal, signum) |
|
158
|
|
|
|
|
159
|
6 |
|
def _teardown_signals(self): |
|
160
|
6 |
|
for signum in self._signals: |
|
161
|
|
|
self._loop.remove_signal_handler(signum) |
|
162
|
|
|
|