terrain.py 14.5 KB
Newer Older
Jelte Jansen's avatar
Jelte Jansen committed
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
# Copyright (C) 2011  Internet Systems Consortium.
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM
# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

16
17
18
19
20
21
22
23
24
#
# This is the 'terrain' in which the lettuce lives. By convention, this is
# where global setup and teardown is defined.
#
# We declare some attributes of the global 'world' variables here, so the
# tests can safely assume they are present.
#
# We also use it to provide scenario invariants, such as resetting data.
#
Jelte Jansen's avatar
Jelte Jansen committed
25

26
27
28
29
from lettuce import *
import subprocess
import os.path
import shutil
30
31
import re
import time
32

33
34
35
36
37
38
39
40
# In order to make sure we start all tests with a 'clean' environment,
# We perform a number of initialization steps, like restoring configuration
# files, and removing generated data files.

# This approach may not scale; if so we should probably provide specific
# initialization steps for scenarios. But until that is shown to be a problem,
# It will keep the scenarios cleaner.

41
42
43
44
45
46
47
# This is a list of files that are freshly copied before each scenario
# The first element is the original, the second is the target that will be
# used by the tests that need them
copylist = [
["configurations/example.org.config.orig", "configurations/example.org.config"]
]

48
49
50
51
52
53
54
55
56
# This is a list of files that, if present, will be removed before a scenario
removelist = [
"data/test_nonexistent_db.sqlite3"
]

# When waiting for output data of a running process, use OUTPUT_WAIT_INTERVAL
# as the interval in which to check again if it has not been found yet.
# If we have waited OUTPUT_WAIT_MAX_INTERVALS times, we will abort with an
# error (so as not to hang indefinitely)
57
OUTPUT_WAIT_INTERVAL = 0.5
58
OUTPUT_WAIT_MAX_INTERVALS = 20
59

60
# class that keeps track of one running process and the files
61
# we created for it.
62
63
64
class RunningProcess:
    def __init__(self, step, process_name, args):
        # set it to none first so destructor won't error if initializer did
Jelte Jansen's avatar
Jelte Jansen committed
65
66
67
68
69
70
71
72
73
        """
        Initialize the long-running process structure, and start the process.
        Parameters:
        step: The scenario step it was called from. This is used for
              determining the output files for redirection of stdout
              and stderr.
        process_name: The name to refer to this running process later.
        args: Array of arguments to pass to Popen().
        """
74
75
76
77
        self.process = None
        self.step = step
        self.process_name = process_name
        self.remove_files_on_exit = True
78
        self._check_output_dir()
79
80
81
82
        self._create_filenames()
        self._start_process(args)

    def _start_process(self, args):
Jelte Jansen's avatar
Jelte Jansen committed
83
84
85
86
87
88
        """
        Start the process.
        Parameters:
        args:
        Array of arguments to pass to Popen().
        """
89
90
91
92
93
94
95
96
97
        stderr_write = open(self.stderr_filename, "w")
        stdout_write = open(self.stdout_filename, "w")
        self.process = subprocess.Popen(args, 1, None, subprocess.PIPE,
                                        stdout_write, stderr_write)
        # open them again, this time for reading
        self.stderr = open(self.stderr_filename, "r")
        self.stdout = open(self.stdout_filename, "r")

    def mangle_filename(self, filebase, extension):
Jelte Jansen's avatar
Jelte Jansen committed
98
99
100
101
102
103
104
105
106
107
        """
        Remove whitespace and non-default characters from a base string,
        and return the substituted value. Whitespace is replaced by an
        underscore. Any other character that is not an ASCII letter, a
        number, a dot, or a hyphen or underscore is removed.
        Parameter:
        filebase: The string to perform the substitution and removal on
        extension: An extension to append to the result value
        Returns the modified filebase with the given extension
        """
108
        filebase = re.sub("\s+", "_", filebase)
109
        filebase = re.sub("[^a-zA-Z0-9.\-_]", "", filebase)
110
111
        return filebase + "." + extension

112
113
114
115
116
    def _check_output_dir(self):
        # We may want to make this overridable by the user, perhaps
        # through an environment variable. Since we currently expect
        # lettuce to be run from our lettuce dir, we shall just use
        # the relative path 'output/'
Jelte Jansen's avatar
Jelte Jansen committed
117
118
119
120
121
122
        """
        Make sure the output directory for stdout/stderr redirection
        exists.
        Fails if it exists but is not a directory, or if it does not
        and we are unable to create it.
        """
123
124
125
126
127
128
        self._output_dir = os.getcwd() + os.sep + "output"
        if not os.path.exists(self._output_dir):
            os.mkdir(self._output_dir)
        assert os.path.isdir(self._output_dir),\
            self._output_dir + " is not a directory."

129
    def _create_filenames(self):
Jelte Jansen's avatar
Jelte Jansen committed
130
131
132
133
134
        """
        Derive the filenames for stdout/stderr redirection from the
        feature, scenario, and process name. The base will be
        "<Feature>-<Scenario>-<process name>.[stdout|stderr]"
        """
135
136
        filebase = self.step.scenario.feature.name + "-" +\
                   self.step.scenario.name + "-" + self.process_name
137
138
139
140
        self.stderr_filename = self._output_dir + os.sep +\
                               self.mangle_filename(filebase, "stderr")
        self.stdout_filename = self._output_dir + os.sep +\
                               self.mangle_filename(filebase, "stdout")
141
142

    def stop_process(self):
Jelte Jansen's avatar
Jelte Jansen committed
143
144
145
146
147
        """
        Stop this process by calling terminate(). Blocks until process has
        exited. If remove_files_on_exit is True, redirected output files
        are removed.
        """
148
149
150
151
152
153
154
155
        if self.process is not None:
            self.process.terminate()
            self.process.wait()
        self.process = None
        if self.remove_files_on_exit:
            self._remove_files()

    def _remove_files(self):
Jelte Jansen's avatar
Jelte Jansen committed
156
157
158
        """
        Remove the files created for redirection of stdout/stderr output.
        """
159
160
161
162
        os.remove(self.stderr_filename)
        os.remove(self.stdout_filename)

    def _wait_for_output_str(self, filename, running_file, strings, only_new):
Jelte Jansen's avatar
Jelte Jansen committed
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
        """
        Wait for a line of output in this process. This will (if only_new is
        False) first check all previous output from the process, and if not
        found, check all output since the last time this method was called.
        For each line in the output, the given strings array is checked. If
        any output lines checked contains one of the strings in the strings
        array, that string (not the line!) is returned.
        Parameters:
        filename: The filename to read previous output from, if applicable.
        running_file: The open file to read new output from.
        strings: Array of strings to look for.
        only_new: If true, only check output since last time this method was
                  called. If false, first check earlier output.
        Returns the matched string.
        Fails if none of the strings was read after 10 seconds
        (OUTPUT_WAIT_INTERVAL * OUTPUT_WAIT_MAX_INTERVALS).
        """
180
181
182
183
184
185
186
        if not only_new:
            full_file = open(filename, "r")
            for line in full_file:
                for string in strings:
                    if line.find(string) != -1:
                        full_file.close()
                        return string
187
188
        wait_count = 0
        while wait_count < OUTPUT_WAIT_MAX_INTERVALS:
189
190
191
192
193
194
195
            where = running_file.tell()
            line = running_file.readline()
            if line:
                for string in strings:
                    if line.find(string) != -1:
                        return string
            else:
196
197
                wait_count += 1
                time.sleep(OUTPUT_WAIT_INTERVAL)
198
                running_file.seek(where)
199
        assert False, "Timeout waiting for process output: " + str(strings)
200
201

    def wait_for_stderr_str(self, strings, only_new = True):
Jelte Jansen's avatar
Jelte Jansen committed
202
        """
Jelte Jansen's avatar
Jelte Jansen committed
203
        Wait for one of the given strings in this process's stderr output.
Jelte Jansen's avatar
Jelte Jansen committed
204
205
206
207
208
209
210
211
        Parameters:
        strings: Array of strings to look for.
        only_new: If true, only check output since last time this method was
                  called. If false, first check earlier output.
        Returns the matched string.
        Fails if none of the strings was read after 10 seconds
        (OUTPUT_WAIT_INTERVAL * OUTPUT_WAIT_MAX_INTERVALS).
        """
212
213
214
215
        return self._wait_for_output_str(self.stderr_filename, self.stderr,
                                         strings, only_new)

    def wait_for_stdout_str(self, strings, only_new = True):
Jelte Jansen's avatar
Jelte Jansen committed
216
        """
Jelte Jansen's avatar
Jelte Jansen committed
217
        Wait for one of the given strings in this process's stdout output.
Jelte Jansen's avatar
Jelte Jansen committed
218
219
220
221
222
223
224
225
        Parameters:
        strings: Array of strings to look for.
        only_new: If true, only check output since last time this method was
                  called. If false, first check earlier output.
        Returns the matched string.
        Fails if none of the strings was read after 10 seconds
        (OUTPUT_WAIT_INTERVAL * OUTPUT_WAIT_MAX_INTERVALS).
        """
226
227
228
229
230
231
232
233
        return self._wait_for_output_str(self.stdout_filename, self.stdout,
                                         strings, only_new)

# Container class for a number of running processes
# i.e. servers like bind10, etc
# one-shot programs like dig or bindctl are started and closed separately
class RunningProcesses:
    def __init__(self):
Jelte Jansen's avatar
Jelte Jansen committed
234
235
236
        """
        Initialize with no running processes.
        """
237
238
239
        self.processes = {}
    
    def add_process(self, step, process_name, args):
Jelte Jansen's avatar
Jelte Jansen committed
240
241
242
243
244
245
246
247
248
249
250
        """
        Start a process with the given arguments, and store it under the given
        name.
        Parameters:
        step: The scenario step it was called from. This is used for
              determining the output files for redirection of stdout
              and stderr.
        process_name: The name to refer to this running process later.
        args: Array of arguments to pass to Popen().
        Fails if a process with the given name is already running.
        """
251
252
253
254
255
        assert process_name not in self.processes,\
            "Process " + name + " already running"
        self.processes[process_name] = RunningProcess(step, process_name, args)

    def get_process(self, process_name):
Jelte Jansen's avatar
Jelte Jansen committed
256
257
258
259
260
261
        """
        Return the Process with the given process name.
        Parameters:
        process_name: The name of the process to return.
        Fails if the process is not running.
        """
262
263
264
265
266
        assert process_name in self.processes,\
            "Process " + name + " unknown"
        return self.processes[process_name]

    def stop_process(self, process_name):
Jelte Jansen's avatar
Jelte Jansen committed
267
268
269
270
271
272
        """
        Stop the Process with the given process name.
        Parameters:
        process_name: The name of the process to return.
        Fails if the process is not running.
        """
273
274
275
276
277
278
        assert process_name in self.processes,\
            "Process " + name + " unknown"
        self.processes[process_name].stop_process()
        del self.processes[process_name]
        
    def stop_all_processes(self):
Jelte Jansen's avatar
Jelte Jansen committed
279
280
281
        """
        Stop all running processes.
        """
282
283
284
285
        for process in self.processes.values():
            process.stop_process()
    
    def keep_files(self):
Jelte Jansen's avatar
Jelte Jansen committed
286
287
288
289
        """
        Keep the redirection files for stdout/stderr output of all processes
        instead of removing them when they are stopped later.
        """
290
291
292
293
        for process in self.processes.values():
            process.remove_files_on_exit = False

    def wait_for_stderr_str(self, process_name, strings, only_new = True):
Jelte Jansen's avatar
Jelte Jansen committed
294
        """
Jelte Jansen's avatar
Jelte Jansen committed
295
        Wait for one of the given strings in the given process's stderr output.
Jelte Jansen's avatar
Jelte Jansen committed
296
297
298
299
300
301
302
303
304
305
        Parameters:
        process_name: The name of the process to check the stderr output of.
        strings: Array of strings to look for.
        only_new: If true, only check output since last time this method was
                  called. If false, first check earlier output.
        Returns the matched string.
        Fails if none of the strings was read after 10 seconds
        (OUTPUT_WAIT_INTERVAL * OUTPUT_WAIT_MAX_INTERVALS).
        Fails if the process is unknown.
        """
306
307
308
309
310
311
        assert process_name in self.processes,\
           "Process " + process_name + " unknown"
        return self.processes[process_name].wait_for_stderr_str(strings,
                                                                only_new)

    def wait_for_stdout_str(self, process_name, strings, only_new = True):
Jelte Jansen's avatar
Jelte Jansen committed
312
        """
Jelte Jansen's avatar
Jelte Jansen committed
313
        Wait for one of the given strings in the given process's stdout output.
Jelte Jansen's avatar
Jelte Jansen committed
314
315
316
317
318
319
320
321
322
323
        Parameters:
        process_name: The name of the process to check the stdout output of.
        strings: Array of strings to look for.
        only_new: If true, only check output since last time this method was
                  called. If false, first check earlier output.
        Returns the matched string.
        Fails if none of the strings was read after 10 seconds
        (OUTPUT_WAIT_INTERVAL * OUTPUT_WAIT_MAX_INTERVALS).
        Fails if the process is unknown.
        """
324
325
326
327
328
        assert process_name in self.processes,\
           "Process " + process_name + " unknown"
        return self.processes[process_name].wait_for_stdout_str(strings,
                                                                only_new)

329
@before.each_scenario
330
def initialize(scenario):
Jelte Jansen's avatar
Jelte Jansen committed
331
332
333
    """
    Global initialization for each scenario.
    """
334
335
336
337
    # Keep track of running processes
    world.processes = RunningProcesses()

    # Convenience variable to access the last query result from querying.py
338
339
340
341
342
343
344
345
    world.last_query_result = None

    # Some tests can modify the settings. If the tests fail half-way, or
    # don't clean up, this can leave configurations or data in a bad state,
    # so we copy them from originals before each scenario
    for item in copylist:
        shutil.copy(item[0], item[1])

346
347
348
349
    for item in removelist:
        if os.path.exists(item):
            os.remove(item)

350
@after.each_scenario
351
def cleanup(scenario):
Jelte Jansen's avatar
Jelte Jansen committed
352
353
354
    """
    Global cleanup for each scenario.
    """
355
356
357
    # Keep output files if the scenario failed
    if not scenario.passed:
        world.processes.keep_files()
358
    # Stop any running processes we may have had around
359
    world.processes.stop_all_processes()
360