summary refs log tree commit diff
path: root/tests/patch_inline_callbacks.py
blob: 220884311caec91ff4b736096cc2efa2e6edf154 (plain) (blame)
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
# -*- coding: utf-8 -*-
# Copyright 2018 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from __future__ import print_function

import functools
import sys

from twisted.internet import defer
from twisted.internet.defer import Deferred
from twisted.python.failure import Failure


def do_patch():
    """
    Patch defer.inlineCallbacks so that it checks the state of the logcontext on exit
    """

    from synapse.logging.context import LoggingContext

    orig_inline_callbacks = defer.inlineCallbacks

    def new_inline_callbacks(f):

        orig = orig_inline_callbacks(f)

        @functools.wraps(f)
        def wrapped(*args, **kwargs):
            start_context = LoggingContext.current_context()

            try:
                res = orig(*args, **kwargs)
            except Exception:
                if LoggingContext.current_context() != start_context:
                    err = "%s changed context from %s to %s on exception" % (
                        f,
                        start_context,
                        LoggingContext.current_context(),
                    )
                    print(err, file=sys.stderr)
                    raise Exception(err)
                raise

            if not isinstance(res, Deferred) or res.called:
                if LoggingContext.current_context() != start_context:
                    err = "%s changed context from %s to %s" % (
                        f,
                        start_context,
                        LoggingContext.current_context(),
                    )
                    # print the error to stderr because otherwise all we
                    # see in travis-ci is the 500 error
                    print(err, file=sys.stderr)
                    raise Exception(err)
                return res

            if LoggingContext.current_context() != LoggingContext.sentinel:
                err = (
                    "%s returned incomplete deferred in non-sentinel context "
                    "%s (start was %s)"
                ) % (f, LoggingContext.current_context(), start_context)
                print(err, file=sys.stderr)
                raise Exception(err)

            def check_ctx(r):
                if LoggingContext.current_context() != start_context:
                    err = "%s completion of %s changed context from %s to %s" % (
                        "Failure" if isinstance(r, Failure) else "Success",
                        f,
                        start_context,
                        LoggingContext.current_context(),
                    )
                    print(err, file=sys.stderr)
                    raise Exception(err)
                return r

            res.addBoth(check_ctx)
            return res

        return wrapped

    defer.inlineCallbacks = new_inline_callbacks