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
|
'''
Mixin for publishing messages to a topic's listeners. This will be
mixed into topicobj.Topic so that a user can use a Topic object to
send a message to the topic's listeners via a publish() method.
:copyright: Copyright 2006-2009 by Oliver Schoenborn, all rights reserved.
:license: BSD, see LICENSE.txt for details.
'''
from publisherbase import PublisherBase
import policies
class PublisherKwargs(PublisherBase):
'''
Publisher used for kwargs protocol, ie when sending message data
via kwargs.
'''
def sendMessage(self, _topicName, **kwargs):
'''Send message of type _topicName to all subscribed listeners,
with message data in kwargs. If topicName is a subtopic, listeners
of topics more general will also get the message. Note also that
kwargs must be compatible with topic.
Note that any listener that lets a raised exception escape will
interrupt the send operation, unless an exception handler was
specified via pub.setListenerExcHandler().
'''
topicMgr = self.getTopicMgr()
topicObj = topicMgr.getOrCreateTopic(_topicName)
# don't care if topic not final: topicObj.getListeners()
# will return nothing if not final but notification will still work
topicObj.publish(**kwargs)
def getMsgProtocol(self):
return 'kwargs'
class PublisherArg1Stage2(PublisherKwargs):
'''
This is used when transitioning from arg1 to kwargs
messaging protocol.
'''
class SenderTooManyKwargs(RuntimeError):
def __init__(self, kwargs, commonArgName):
extra = kwargs.copy()
del extra[commonArgName]
msg = 'Sender has too many kwargs (%s)' % (extra.keys(),)
RuntimeError.__init__(self, msg)
class SenderWrongKwargName(RuntimeError):
def __init__(self, actualKwargName, commonArgName):
msg = 'Sender uses wrong kwarg name ("%s" instead of "%s")' \
% (actualKwargName, commonArgName)
RuntimeError.__init__(self, msg)
def __init__(self, treeConfig = None):
PublisherKwargs.__init__(self, treeConfig)
from datamsg import Message
self.Msg = Message
def sendMessage(self, _topicName, **kwarg):
commonArgName = policies.msgDataArgName
if len(kwarg) > 1:
raise self.SenderTooManyKwargs(kwarg, commonArgName)
elif len(kwarg) == 1 and not kwarg.has_key(commonArgName):
raise self.SenderWrongKwargName(kwarg.keys()[0], commonArgName)
data = kwarg.get(commonArgName, None)
kwargs = { commonArgName: self.Msg( _topicName, data) }
PublisherKwargs.sendMessage( self, _topicName, **kwargs )
def getMsgProtocol(self):
return 'kwarg1'
if policies.msgProtocolTransStage is None:
Publisher = PublisherKwargs
else:
Publisher = PublisherArg1Stage2
#print 'Using protocol', Publisher
|
