aboutsummaryrefslogtreecommitdiffstats
path: root/test/remote_test.py
blob: f5b3c620cc4d51239341331db6828025e1bb7e33 (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
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
#!/usr/bin/env python

import inspect
import os
import unittest
from framework import VppTestCase
from multiprocessing import Process, Pipe
from pickle import dumps
import six
from six import moves
import sys
if sys.version_info <= (3, 4):
    from aenum import IntEnum
else:
    from enum import IntEnum

if sys.version_info <= (3, 6):
    from aenum import IntFlag
else:
    from enum import IntFlag


class SerializableClassCopy(object):
    """
    Empty class used as a basis for a serializable copy of another class.
    """
    pass


class RemoteClassAttr(object):
    """
    Wrapper around attribute of a remotely executed class.
    """

    def __init__(self, remote, attr):
        self._path = [attr] if attr else []
        self._remote = remote

    def path_to_str(self):
        return '.'.join(self._path)

    def get_remote_value(self):
        return self._remote._remote_exec(RemoteClass.GET, self.path_to_str())

    def __repr__(self):
        return self._remote._remote_exec(RemoteClass.REPR, self.path_to_str())

    def __str__(self):
        return self._remote._remote_exec(RemoteClass.STR, self.path_to_str())

    def __getattr__(self, attr):
        if attr[0] == '_':
            if not (attr.startswith('__') and attr.endswith('__')):
                raise AttributeError
        self._path.append(attr)
        return self

    def __setattr__(self, attr, val):
        if attr[0] == '_':
            if not (attr.startswith('__') and attr.endswith('__')):
                super(RemoteClassAttr, self).__setattr__(attr, val)
                return
        self._path.append(attr)
        self._remote._remote_exec(RemoteClass.SETATTR, self.path_to_str(),
                                  True, value=val)

    def __call__(self, *args, **kwargs):
        return self._remote._remote_exec(RemoteClass.CALL, self.path_to_str(),
                                         True, *args, **kwargs)


class RemoteClass(Process):
    """
    This class can wrap around and adapt the interface of another class,
    and then delegate its execution to a newly forked child process.
    Usage:
        # Create a remotely executed instance of MyClass
        object = RemoteClass(MyClass, arg1='foo', arg2='bar')
        object.start_remote()
        # Access the object normally as if it was an instance of your class.
        object.my_attribute = 20
        print object.my_attribute
        print object.my_method(object.my_attribute)
        object.my_attribute.nested_attribute = 'test'
        # If you need the value of a remote attribute, use .get_remote_value
        method. This method is automatically called when needed in the context
        of a remotely executed class. E.g.:
        if (object.my_attribute.get_remote_value() > 20):
            object.my_attribute2 = object.my_attribute
        # Destroy the instance
        object.quit_remote()
        object.terminate()
    """

    GET = 0       # Get attribute remotely
    CALL = 1      # Call method remotely
    SETATTR = 2   # Set attribute remotely
    REPR = 3      # Get representation of a remote object
    STR = 4       # Get string representation of a remote object
    QUIT = 5      # Quit remote execution

    PIPE_PARENT = 0  # Parent end of the pipe
    PIPE_CHILD = 1  # Child end of the pipe

    DEFAULT_TIMEOUT = 2  # default timeout for an operation to execute

    def __init__(self, cls, *args, **kwargs):
        super(RemoteClass, self).__init__()
        self._cls = cls
        self._args = args
        self._kwargs = kwargs
        self._timeout = RemoteClass.DEFAULT_TIMEOUT
        self._pipe = Pipe()  # pipe for input/output arguments

    def __repr__(self):
        return moves.reprlib.repr(RemoteClassAttr(self, None))

    def __str__(self):
        return str(RemoteClassAttr(self, None))

    def __call__(self, *args, **kwargs):
        return self.RemoteClassAttr(self, None)()

    def __getattr__(self, attr):
        if attr[0] == '_' or not self.is_alive():
            if not (attr.startswith('__') and attr.endswith('__')):
                if hasattr(super(RemoteClass, self), '__getattr__'):
                    return super(RemoteClass, self).__getattr__(attr)
                raise AttributeError
        return RemoteClassAttr(self, attr)

    def __setattr__(self, attr, val):
        if attr[0] == '_' or not self.is_alive():
            if not (attr.startswith('__') and attr.endswith('__')):
                super(RemoteClass, self).__setattr__(attr, val)
                return
        setattr(RemoteClassAttr(self, None), attr, val)

    def _remote_exec(self, op, path=None, ret=True, *args, **kwargs):
        """
        Execute given operation on a given, possibly nested, member remotely.
        """
        # automatically resolve remote objects in the arguments
        mutable_args = list(args)
        for i, val in enumerate(mutable_args):
            if isinstance(val, RemoteClass) or \
               isinstance(val, RemoteClassAttr):
                mutable_args[i] = val.get_remote_value()
        args = tuple(mutable_args)
        for key, val in six.iteritems(kwargs):
            if isinstance(val, RemoteClass) or \
               isinstance(val, RemoteClassAttr):
                kwargs[key] = val.get_remote_value()
        # send request
        args = self._make_serializable(args)
        kwargs = self._make_serializable(kwargs)
        self._pipe[RemoteClass.PIPE_PARENT].send((op, path, args, kwargs))
        if not ret:
            # no return value expected
            return None
        timeout = self._timeout
        # adjust timeout specifically for the .sleep method
        if path.split('.')[-1] == 'sleep':
            if args and isinstance(args[0], (long, int)):
                timeout += args[0]
            elif 'timeout' in kwargs:
                timeout += kwargs['timeout']
        if not self._pipe[RemoteClass.PIPE_PARENT].poll(timeout):
            return None
        try:
            rv = self._pipe[RemoteClass.PIPE_PARENT].recv()
            rv = self._deserialize(rv)
            return rv
        except EOFError:
            return None

    def _get_local_object(self, path):
        """
        Follow the path to obtain a reference on the addressed nested attribute
        """
        obj = self._instance
        for attr in path:
            obj = getattr(obj, attr)
        return obj

    def _get_local_value(self, path):
        try:
            return self._get_local_object(path)
        except AttributeError:
            return None

    def _call_local_method(self, path, *args, **kwargs):
        try:
            method = self._get_local_object(path)
            return method(*args, **kwargs)
        except AttributeError:
            return None

    def _set_local_attr(self, path, value):
        try:
            obj = self._get_local_object(path[:-1])
            setattr(obj, path[-1], value)
        except AttributeError:
            pass
        return None

    def _get_local_repr(self, path):
        try:
            obj = self._get_local_object(path)
            return moves.reprlib.repr(obj)
        except AttributeError:
            return None

    def _get_local_str(self, path):
        try:
            obj = self._get_local_object(path)
            return str(obj)
        except AttributeError:
            return None

    def _serializable(self, obj):
        """ Test if the given object is serializable """
        try:
            dumps(obj)
            return True
        except:
            return False

    def _make_obj_serializable(self, obj):
        """
        Make a serializable copy of an object.
        Members which are difficult/impossible to serialize are stripped.
        """
        if self._serializable(obj):
            return obj  # already serializable

        copy = SerializableClassCopy()

        """
        Dictionaries can hold complex values, so we split keys and values into
        separate lists and serialize them individually.
        """
        if (type(obj) is dict):
            copy.type = type(obj)
            copy.k_list = list()
            copy.v_list = list()
            for k, v in obj.items():
                copy.k_list.append(self._make_serializable(k))
                copy.v_list.append(self._make_serializable(v))
            return copy

        # copy at least serializable attributes and properties
        for name, member in inspect.getmembers(obj):
            if name[0] == '_':  # skip private members
                if not (name.startswith('__') and name.endswith('__')):
                    continue
            if callable(member) and not isinstance(member, property):
                continue
            if not self._serializable(member):
                continue
            setattr(copy, name, member)
        return copy

    def _make_serializable(self, obj):
        """
        Make a serializable copy of an object or a list/tuple of objects.
        Members which are difficult/impossible to serialize are stripped.
        """
        if (type(obj) is list) or (type(obj) is tuple):
            rv = []
            for item in obj:
                rv.append(self._make_serializable(item))
            if type(obj) is tuple:
                rv = tuple(rv)
            return rv
        elif (isinstance(obj, IntEnum) or isinstance(obj, IntFlag)):
            return obj.value
        else:
            return self._make_obj_serializable(obj)

    def _deserialize_obj(self, obj):
        if (hasattr(obj, 'type')):
            if obj.type is dict:
                _obj = dict()
                for k, v in zip(obj.k_list, obj.v_list):
                    _obj[self._deserialize(k)] = self._deserialize(v)
            return _obj
        return obj

    def _deserialize(self, obj):
        if (type(obj) is list) or (type(obj) is tuple):
            rv = []
            for item in obj:
                rv.append(self._deserialize(item))
            if type(obj) is tuple:
                rv = tuple(rv)
            return rv
        else:
            return self._deserialize_obj(obj)

    def start_remote(self):
        """ Start remote execution """
        self.start()

    def quit_remote(self):
        """ Quit remote execution """
        self._remote_exec(RemoteClass.QUIT, None, False)

    def get_remote_value(self):
        """ Get value of a remotely held object """
        return RemoteClassAttr(self, None).get_remote_value()

    def set_request_timeout(self, timeout):
        """ Change request timeout """
        self._timeout = timeout

    def run(self):
        """
        Create instance of the wrapped class and execute operations
        on it as requested by the parent process.
        """
        self._instance = self._cls(*self._args, **self._kwargs)
        while True:
            try:
                rv = None
                # get request from the parent process
                (op, path, args,
                 kwargs) = self._pipe[RemoteClass.PIPE_CHILD].recv()
                args = self._deserialize(args)
                kwargs = self._deserialize(kwargs)
                path = path.split('.') if path else []
                if op == RemoteClass.GET:
                    rv = self._get_local_value(path)
                elif op == RemoteClass.CALL:
                    rv = self._call_local_method(path, *args, **kwargs)
                elif op == RemoteClass.SETATTR and 'value' in kwargs:
                    self._set_local_attr(path, kwargs['value'])
                elif op == RemoteClass.REPR:
                    rv = self._get_local_repr(path)
                elif op == RemoteClass.STR:
                    rv = self._get_local_str(path)
                elif op == RemoteClass.QUIT:
                    break
                else:
                    continue
                # send return value
                if not self._serializable(rv):
                    rv = self._make_serializable(rv)
                self._pipe[RemoteClass.PIPE_CHILD].send(rv)
            except EOFError:
                break
        self._instance = None  # destroy the instance


@unittest.skip("Remote Vpp Test Case Class")
class RemoteVppTestCase(VppTestCase):
    """ Re-use VppTestCase to create remote VPP segment

        In your test case:

        @classmethod
        def setUpClass(cls):
            # fork new process before clinet connects to VPP
            cls.remote_test = RemoteClass(RemoteVppTestCase)

            # start remote process
            cls.remote_test.start_remote()

            # set up your test case
            super(MyTestCase, cls).setUpClass()

            # set up remote test
            cls.remote_test.setUpClass(cls.tempdir)

        @classmethod
        def tearDownClass(cls):
            # tear down remote test
            cls.remote_test.tearDownClass()

            # stop remote process
            cls.remote_test.quit_remote()

            # tear down your test case
            super(MyTestCase, cls).tearDownClass()
    """

    def __init__(self):
        super(RemoteVppTestCase, self).__init__("emptyTest")

    # Note: __del__ is a 'Finalizer" not a 'Destructor'.
    # https://docs.python.org/3/reference/datamodel.html#object.__del__
    def __del__(self):
        if hasattr(self, "vpp"):
            self.vpp.poll()
            if self.vpp.returncode is None:
                self.vpp.terminate()
                self.vpp.communicate()

    @classmethod
    def setUpClass(cls, tempdir):
        # disable features unsupported in remote VPP
        orig_env = dict(os.environ)
        if 'STEP' in os.environ:
            del os.environ['STEP']
        if 'DEBUG' in os.environ:
            del os.environ['DEBUG']
        cls.tempdir_prefix = os.path.basename(tempdir) + "/"
        super(RemoteVppTestCase, cls).setUpClass()
        os.environ = orig_env

    @unittest.skip("Empty test")
    def emptyTest(self):
        """ Do nothing """
        pass

    def setTestFunctionInfo(self, name, doc):
        """
        Store the name and documentation string of currently executed test
        in the main VPP for logging purposes.
        """
        self._testMethodName = name
        self._testMethodDoc = doc