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
|
from .. import stateobject, utils, version
from ..proxy import ServerConnection, ClientConnection
import copy
class BackreferenceMixin(object):
"""
If an attribute from the _backrefattr tuple is set,
this mixin sets a reference back on the attribute object.
Example:
e = Error()
f = Flow()
f.error = e
assert f is e.flow
"""
_backrefattr = tuple()
def __setattr__(self, key, value):
super(BackreferenceMixin, self).__setattr__(key, value)
if key in self._backrefattr and value is not None:
setattr(value, self._backrefname, self)
class Error(stateobject.SimpleStateObject):
"""
An Error.
This is distinct from an HTTP error response (say, a code 500), which
is represented by a normal Response object. This class is responsible
for indicating errors that fall outside of normal HTTP communications,
like interrupted connections, timeouts, protocol errors.
Exposes the following attributes:
flow: Flow object
msg: Message describing the error
timestamp: Seconds since the epoch
"""
def __init__(self, msg, timestamp=None):
"""
@type msg: str
@type timestamp: float
"""
self.flow = None # will usually be set by the flow backref mixin
self.msg = msg
self.timestamp = timestamp or utils.timestamp()
_stateobject_attributes = dict(
msg=str,
timestamp=float
)
def __str__(self):
return self.msg
@classmethod
def _from_state(cls, state):
f = cls(None) # the default implementation assumes an empty constructor. Override accordingly.
f._load_state(state)
return f
def copy(self):
c = copy.copy(self)
return c
class Flow(stateobject.SimpleStateObject, BackreferenceMixin):
def __init__(self, conntype, client_conn, server_conn):
self.conntype = conntype
self.client_conn = client_conn
"""@type: ClientConnection"""
self.server_conn = server_conn
"""@type: ServerConnection"""
self.error = None
"""@type: Error"""
self._backup = None
_backrefattr = ("error",)
_backrefname = "flow"
_stateobject_attributes = dict(
error=Error,
client_conn=ClientConnection,
server_conn=ServerConnection,
conntype=str
)
def _get_state(self):
d = super(Flow, self)._get_state()
d.update(version=version.IVERSION)
return d
def __eq__(self, other):
return self is other
def copy(self):
f = copy.copy(self)
f.client_conn = self.client_conn.copy()
f.server_conn = self.server_conn.copy()
if self.error:
f.error = self.error.copy()
return f
def modified(self):
"""
Has this Flow been modified?
"""
if self._backup:
return self._backup != self._get_state()
else:
return False
def backup(self, force=False):
"""
Save a backup of this Flow, which can be reverted to using a
call to .revert().
"""
if not self._backup:
self._backup = self._get_state()
def revert(self):
"""
Revert to the last backed up state.
"""
if self._backup:
self._load_state(self._backup)
self._backup = None
|
