author | Sverre Rabbelier <srabbelier@gmail.com> |
Sat, 28 Feb 2009 12:10:19 +0000 | |
changeset 1554 | 163c879d1ffe |
parent 54 | 03e267d67478 |
permissions | -rw-r--r-- |
54
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
1 |
"""Thread-local objects |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
2 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
3 |
(Note that this module provides a Python version of thread |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
4 |
threading.local class. Depending on the version of Python you're |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
5 |
using, there may be a faster one available. You should always import |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
6 |
the local class from threading.) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
7 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
8 |
Thread-local objects support the management of thread-local data. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
9 |
If you have data that you want to be local to a thread, simply create |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
10 |
a thread-local object and use its attributes: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
11 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
12 |
>>> mydata = local() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
13 |
>>> mydata.number = 42 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
14 |
>>> mydata.number |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
15 |
42 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
16 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
17 |
You can also access the local-object's dictionary: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
18 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
19 |
>>> mydata.__dict__ |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
20 |
{'number': 42} |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
21 |
>>> mydata.__dict__.setdefault('widgets', []) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
22 |
[] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
23 |
>>> mydata.widgets |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
24 |
[] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
25 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
26 |
What's important about thread-local objects is that their data are |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
27 |
local to a thread. If we access the data in a different thread: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
28 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
29 |
>>> log = [] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
30 |
>>> def f(): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
31 |
... items = mydata.__dict__.items() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
32 |
... items.sort() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
33 |
... log.append(items) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
34 |
... mydata.number = 11 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
35 |
... log.append(mydata.number) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
36 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
37 |
>>> import threading |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
38 |
>>> thread = threading.Thread(target=f) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
39 |
>>> thread.start() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
40 |
>>> thread.join() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
41 |
>>> log |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
42 |
[[], 11] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
43 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
44 |
we get different data. Furthermore, changes made in the other thread |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
45 |
don't affect data seen in this thread: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
46 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
47 |
>>> mydata.number |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
48 |
42 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
49 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
50 |
Of course, values you get from a local object, including a __dict__ |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
51 |
attribute, are for whatever thread was current at the time the |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
52 |
attribute was read. For that reason, you generally don't want to save |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
53 |
these values across threads, as they apply only to the thread they |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
54 |
came from. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
55 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
56 |
You can create custom local objects by subclassing the local class: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
57 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
58 |
>>> class MyLocal(local): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
59 |
... number = 2 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
60 |
... initialized = False |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
61 |
... def __init__(self, **kw): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
62 |
... if self.initialized: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
63 |
... raise SystemError('__init__ called too many times') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
64 |
... self.initialized = True |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
65 |
... self.__dict__.update(kw) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
66 |
... def squared(self): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
67 |
... return self.number ** 2 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
68 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
69 |
This can be useful to support default values, methods and |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
70 |
initialization. Note that if you define an __init__ method, it will be |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
71 |
called each time the local object is used in a separate thread. This |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
72 |
is necessary to initialize each thread's dictionary. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
73 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
74 |
Now if we create a local object: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
75 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
76 |
>>> mydata = MyLocal(color='red') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
77 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
78 |
Now we have a default number: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
79 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
80 |
>>> mydata.number |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
81 |
2 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
82 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
83 |
an initial color: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
84 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
85 |
>>> mydata.color |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
86 |
'red' |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
87 |
>>> del mydata.color |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
88 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
89 |
And a method that operates on the data: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
90 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
91 |
>>> mydata.squared() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
92 |
4 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
93 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
94 |
As before, we can access the data in a separate thread: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
95 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
96 |
>>> log = [] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
97 |
>>> thread = threading.Thread(target=f) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
98 |
>>> thread.start() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
99 |
>>> thread.join() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
100 |
>>> log |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
101 |
[[('color', 'red'), ('initialized', True)], 11] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
102 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
103 |
without affecting this thread's data: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
104 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
105 |
>>> mydata.number |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
106 |
2 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
107 |
>>> mydata.color |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
108 |
Traceback (most recent call last): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
109 |
... |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
110 |
AttributeError: 'MyLocal' object has no attribute 'color' |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
111 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
112 |
Note that subclasses can define slots, but they are not thread |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
113 |
local. They are shared across threads: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
114 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
115 |
>>> class MyLocal(local): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
116 |
... __slots__ = 'number' |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
117 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
118 |
>>> mydata = MyLocal() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
119 |
>>> mydata.number = 42 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
120 |
>>> mydata.color = 'red' |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
121 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
122 |
So, the separate thread: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
123 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
124 |
>>> thread = threading.Thread(target=f) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
125 |
>>> thread.start() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
126 |
>>> thread.join() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
127 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
128 |
affects what we see: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
129 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
130 |
>>> mydata.number |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
131 |
11 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
132 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
133 |
>>> del mydata |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
134 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
135 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
136 |
# Threading import is at end |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
137 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
138 |
class _localbase(object): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
139 |
__slots__ = '_local__key', '_local__args', '_local__lock' |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
140 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
141 |
def __new__(cls, *args, **kw): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
142 |
self = object.__new__(cls) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
143 |
key = '_local__key', 'thread.local.' + str(id(self)) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
144 |
object.__setattr__(self, '_local__key', key) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
145 |
object.__setattr__(self, '_local__args', (args, kw)) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
146 |
object.__setattr__(self, '_local__lock', RLock()) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
147 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
148 |
if args or kw and (cls.__init__ is object.__init__): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
149 |
raise TypeError("Initialization arguments are not supported") |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
150 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
151 |
# We need to create the thread dict in anticipation of |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
152 |
# __init__ being called, to make sure we don't call it |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
153 |
# again ourselves. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
154 |
dict = object.__getattribute__(self, '__dict__') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
155 |
currentThread().__dict__[key] = dict |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
156 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
157 |
return self |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
158 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
159 |
def _patch(self): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
160 |
key = object.__getattribute__(self, '_local__key') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
161 |
d = currentThread().__dict__.get(key) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
162 |
if d is None: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
163 |
d = {} |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
164 |
currentThread().__dict__[key] = d |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
165 |
object.__setattr__(self, '__dict__', d) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
166 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
167 |
# we have a new instance dict, so call out __init__ if we have |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
168 |
# one |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
169 |
cls = type(self) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
170 |
if cls.__init__ is not object.__init__: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
171 |
args, kw = object.__getattribute__(self, '_local__args') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
172 |
cls.__init__(self, *args, **kw) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
173 |
else: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
174 |
object.__setattr__(self, '__dict__', d) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
175 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
176 |
class local(_localbase): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
177 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
178 |
def __getattribute__(self, name): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
179 |
lock = object.__getattribute__(self, '_local__lock') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
180 |
lock.acquire() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
181 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
182 |
_patch(self) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
183 |
return object.__getattribute__(self, name) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
184 |
finally: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
185 |
lock.release() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
186 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
187 |
def __setattr__(self, name, value): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
188 |
lock = object.__getattribute__(self, '_local__lock') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
189 |
lock.acquire() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
190 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
191 |
_patch(self) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
192 |
return object.__setattr__(self, name, value) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
193 |
finally: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
194 |
lock.release() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
195 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
196 |
def __delattr__(self, name): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
197 |
lock = object.__getattribute__(self, '_local__lock') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
198 |
lock.acquire() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
199 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
200 |
_patch(self) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
201 |
return object.__delattr__(self, name) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
202 |
finally: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
203 |
lock.release() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
204 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
205 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
206 |
def __del__(): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
207 |
threading_enumerate = enumerate |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
208 |
__getattribute__ = object.__getattribute__ |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
209 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
210 |
def __del__(self): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
211 |
key = __getattribute__(self, '_local__key') |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
212 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
213 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
214 |
threads = list(threading_enumerate()) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
215 |
except: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
216 |
# if enumerate fails, as it seems to do during |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
217 |
# shutdown, we'll skip cleanup under the assumption |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
218 |
# that there is nothing to clean up |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
219 |
return |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
220 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
221 |
for thread in threads: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
222 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
223 |
__dict__ = thread.__dict__ |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
224 |
except AttributeError: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
225 |
# Thread is dying, rest in peace |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
226 |
continue |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
227 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
228 |
if key in __dict__: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
229 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
230 |
del __dict__[key] |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
231 |
except KeyError: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
232 |
pass # didn't have anything in this thread |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
233 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
234 |
return __del__ |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
235 |
__del__ = __del__() |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
236 |
|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
237 |
try: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
238 |
from threading import currentThread, enumerate, RLock |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
239 |
except ImportError: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
240 |
from dummy_threading import currentThread, enumerate, RLock |