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
| | #! /usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0-or-later
#
# Copyright Red Hat
# Author: David Gibson <david@gibson.dropbear.id.au>
"""
Test A Simple Socket Transport
tasst/snh.py - Simulated network hosts for testing
"""
import contextlib
import subprocess
import sys
import exeter
STDOUT = 1
class SnhProcess(contextlib.AbstractContextManager):
"""
A background process running on a SimNetHost
"""
def __init__(self, snh, *cmd, check=True, context_timeout=1.0, **kwargs):
self.snh = snh
self.cmd = cmd
self.check = check
self.context_timeout = float(context_timeout)
self.kwargs = kwargs
def __enter__(self):
self.popen = subprocess.Popen(self.cmd, **self.kwargs)
return self
def run(self, **kwargs):
stdout, stderr = self.popen.communicate(**kwargs)
cp = subprocess.CompletedProcess(self.popen.args,
self.popen.returncode,
stdout, stderr)
if self.check:
cp.check_returncode()
return cp
def terminate(self):
self.popen.terminate()
def kill(self):
self.popen.kill()
def __exit__(self, *exc_details):
try:
self.popen.wait(timeout=self.context_timeout)
except subprocess.TimeoutExpired as e:
self.terminate()
try:
self.popen.wait(timeout=self.context_timeout)
except subprocess.TimeoutExpired:
self.kill()
raise e
class SimNetHost(contextlib.AbstractContextManager):
"""
A (usually virtual or simulated) location where we can execute
commands and configure networks.
"""
def __init__(self, name):
self.name = name # For debugging
def hostify(self, *cmd, **kwargs):
raise NotImplementedError
def __enter__(self):
return self
def __exit__(self, *exc_details):
pass
def output(self, *cmd, **kwargs):
proc = self.fg(*cmd, capture=STDOUT, **kwargs)
return proc.stdout
def fg(self, *cmd, timeout=None, **kwargs):
# We don't use subprocess.run() because it kills without
# attempting to terminate on timeout
with self.bg(*cmd, **kwargs) as proc:
res = proc.run(timeout=timeout)
return res
def bg(self, *cmd, capture=None, **kwargs):
if capture == STDOUT:
kwargs['stdout'] = subprocess.PIPE
hostcmd, kwargs = self.hostify(*cmd, **kwargs)
proc = SnhProcess(self, *hostcmd, **kwargs)
print(f"SimNetHost {self.name}: Started {cmd} => {proc}",
file=sys.stderr)
return proc
# Internal tests
def test_true(self):
with self as snh:
snh.fg('true')
def test_false(self):
with self as snh:
exeter.assert_raises(subprocess.CalledProcessError,
snh.fg, 'false')
def test_echo(self):
msg = 'Hello tasst'
with self as snh:
out = snh.output('echo', f'{msg}')
exeter.assert_eq(out, msg.encode('utf-8') + b'\n')
def test_timeout(self):
with self as snh:
exeter.assert_raises(subprocess.TimeoutExpired, snh.fg,
'sleep', 'infinity', timeout=0.1, check=False)
def test_bg_true(self):
with self as snh:
with snh.bg('true'):
pass
def test_bg_false(self):
with self as snh:
with snh.bg('false') as proc:
exeter.assert_raises(subprocess.CalledProcessError, proc.run)
def test_bg_echo(self):
msg = 'Hello tasst'
with self as snh:
with snh.bg('echo', f'{msg}', capture=STDOUT) as proc:
res = proc.run()
exeter.assert_eq(res.stdout, msg.encode('utf-8') + b'\n')
def test_bg_timeout(self):
with self as snh:
with snh.bg('sleep', 'infinity') as proc:
exeter.assert_raises(subprocess.TimeoutExpired,
proc.run, timeout=0.1)
proc.terminate()
def test_bg_context_timeout(self):
with self as snh:
def run_timeout():
with snh.bg('sleep', 'infinity', context_timeout=0.1):
pass
exeter.assert_raises(subprocess.TimeoutExpired, run_timeout)
SELFTESTS = [test_true, test_false, test_echo, test_timeout,
test_bg_true, test_bg_false, test_bg_echo, test_bg_timeout,
test_bg_context_timeout]
@classmethod
def selftest(cls, setup):
"Register standard snh tests for instance returned by setup"
for t in cls.SELFTESTS:
testid = f'{setup.__qualname__}|{t.__qualname__}'
exeter.register_pipe(testid, setup, t)
class RealHost(SimNetHost):
"""Represents the host on which the tests are running (as opposed
to some simulated host created by the tests)
"""
def __init__(self):
super().__init__('REAL_HOST')
def hostify(self, *cmd, capable=False, **kwargs):
assert not capable, \
"BUG: Shouldn't run commands with capabilities on host"
return cmd, kwargs
SimNetHost.selftest(RealHost)
|