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
|
import sys
from SimpleXMLRPCServer import SimpleXMLRPCServer
import pwd
import os
import stat
from os.path import isdir, dirname, abspath, join, isfile
import signal
from multiprocessing import Process, Queue
import subprocess
import re
# import json
# Local imports.
from settings import SERVER_TIMEOUT
MY_DIR = abspath(dirname(__file__))
# Raised when the code times-out.
# c.f. http://pguides.net/python/timeout-a-function
class TimeoutException(Exception):
pass
def timeout_handler(signum, frame):
"""A handler for the ALARM signal."""
raise TimeoutException('Code took too long to run.')
def create_signal_handler():
"""Add a new signal handler for the execution of this code."""
prev_handler = signal.signal(signal.SIGALRM, timeout_handler)
signal.alarm(SERVER_TIMEOUT)
return prev_handler
def set_original_signal_handler(old_handler=None):
"""Set back any original signal handler."""
if old_handler is not None:
signal.signal(signal.SIGALRM, old_handler)
return
else:
raise Exception("Signal Handler: object cannot be NoneType")
def delete_signal_handler():
signal.alarm(0)
return
class CodeEvaluator(object):
"""Tests the code obtained from Code Server"""
# def __init__(self, test_case_data, test, language, user_answer,
# ref_code_path=None, in_dir=None):
def __init__(self, in_dir, **kwargs):
msg = 'Code took more than %s seconds to run. You probably '\
'have an infinite loop in your code.' % SERVER_TIMEOUT
self.timeout_msg = msg
# self.test_case_data = test_case_data
# self.language = language.lower() #@@@remove
# self.user_answer = user_answer #@@@specific to check-code
# self.ref_code_path = ref_code_path #@@@specific to check-code
# self.test = test #@@@specific to check-code
self.in_dir = in_dir #@@@Common for all, no change
self.test_case_args = None #@@@no change
# Public Protocol ##########
# @classmethod
# def from_json(cls, language, json_data, in_dir):
# json_data = json.loads(json_data)
# # test_case_data = json_data.get("test_case_data")
# user_answer = json_data.get("user_answer")
# ref_code_path = json_data.get("ref_code_path")
# test = json_data.get("test")
# # instance = cls(test_case_data, test, language, user_answer, ref_code_path,
# # in_dir)
# instance = cls(test, language, user_answer, ref_code_path,
# in_dir)
# return instance
# def evaluate(self):
def evaluate(self, **kwargs):
"""Evaluates given code with the test cases based on
given arguments in test_case_data.
The ref_code_path is a path to the reference code.
The reference code will call the function submitted by the student.
The reference code will check for the expected output.
If the path's start with a "/" then we assume they are absolute paths.
If not, we assume they are relative paths w.r.t. the location of this
code_server script.
If the optional `in_dir` keyword argument is supplied it changes the
directory to that directory (it does not change it back to the original
when done).
Returns
-------
A tuple: (success, error message).
"""
self.setup()
# success, err = self.safe_evaluate(self.test_case_args)
success, err = self.safe_evaluate(**kwargs)
self.teardown()
result = {'success': success, 'error': err}
return result
# Private Protocol ##########
def setup(self):
self._change_dir(self.in_dir)
# def safe_evaluate(self, args):
def safe_evaluate(self, **kwargs):
# Add a new signal handler for the execution of this code.
prev_handler = create_signal_handler()
success = False
# args = args or []
# Do whatever testing needed.
try:
# success, err = self.check_code(*args)
success, err = self.check_code(**kwargs)
except TimeoutException:
err = self.timeout_msg
except:
_type, value = sys.exc_info()[:2]
err = "Error: {0}".format(repr(value))
finally:
# Set back any original signal handler.
set_original_signal_handler(prev_handler)
return success, err
def teardown(self):
# Cancel the signal
delete_signal_handler()
def check_code(self):
raise NotImplementedError("check_code method not implemented")
def create_submit_code_file(self, file_name):
""" Write the code (`answer`) to a file and set the file path"""
submit_f = open(file_name, 'w')
submit_f.write(self.user_answer.lstrip())
submit_f.close()
submit_path = abspath(submit_f.name)
return submit_path
def _set_file_as_executable(self, fname):
os.chmod(fname, stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR
| stat.S_IRGRP | stat.S_IWGRP | stat.S_IXGRP
| stat.S_IROTH | stat.S_IWOTH | stat.S_IXOTH)
def _set_test_code_file_path(self, ref_path=None, test_case_path=None):
if ref_path and not ref_path.startswith('/'):
ref_path = join(MY_DIR, ref_path)
if test_case_path and not test_case_path.startswith('/'):
test_case_path = join(MY_DIR, test_case_path)
return ref_path, test_case_path
def _run_command(self, cmd_args, *args, **kw):
"""Run a command in a subprocess while blocking, the process is killed
if it takes more than 2 seconds to run. Return the Popen object, the
stdout and stderr.
"""
try:
proc = subprocess.Popen(cmd_args, *args, **kw)
stdout, stderr = proc.communicate()
except TimeoutException:
# Runaway code, so kill it.
proc.kill()
# Re-raise exception.
raise
return proc, stdout, stderr
def _compile_command(self, cmd, *args, **kw):
"""Compiles C/C++/java code and returns errors if any.
Run a command in a subprocess while blocking, the process is killed
if it takes more than 2 seconds to run. Return the Popen object, the
stderr.
"""
try:
proc_compile = subprocess.Popen(cmd, shell=True, stdin=None,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc_compile.communicate()
except TimeoutException:
# Runaway code, so kill it.
proc_compile.kill()
# Re-raise exception.
raise
return proc_compile, err
def _change_dir(self, in_dir):
if in_dir is not None and isdir(in_dir):
os.chdir(in_dir)
def _remove_null_substitute_char(self, string):
"""Returns a string without any null and substitute characters"""
stripped = ""
for c in string:
if ord(c) is not 26 and ord(c) is not 0:
stripped = stripped + c
return ''.join(stripped)
|
