1
2 """Base classes handy for use with PB clients.
3 """
4
5 from twisted.spread import pb
6
7 from twisted.spread.pb import PBClientFactory
8 from twisted.internet import protocol
9 from twisted.python import log
10
16
19 """Reconnecting client factory for PB brokers.
20
21 Like PBClientFactory, but if the connection fails or is lost, the factory
22 will attempt to reconnect.
23
24 Instead of using f.getRootObject (which gives a Deferred that can only
25 be fired once), override the gotRootObject method.
26
27 Instead of using the newcred f.login (which is also one-shot), call
28 f.startLogin() with the credentials and client, and override the
29 gotPerspective method.
30
31 Instead of using the oldcred f.getPerspective (also one-shot), call
32 f.startGettingPerspective() with the same arguments, and override
33 gotPerspective.
34
35 gotRootObject and gotPerspective will be called each time the object is
36 received (once per successful connection attempt). You will probably want
37 to use obj.notifyOnDisconnect to find out when the connection is lost.
38
39 If an authorization error occurs, failedToGetPerspective() will be
40 invoked.
41
42 To use me, subclass, then hand an instance to a connector (like
43 TCPClient).
44 """
45
47 PBClientFactory.__init__(self)
48 self._doingLogin = False
49 self._doingGetPerspective = False
50
59
65
74
75
76
78 raise RuntimeError, "getPerspective is one-shot: use startGettingPerspective instead"
79
82 self._doingGetPerspective = True
83 if perspectiveName == None:
84 perspectiveName = username
85 self._oldcredArgs = (username, password, serviceName,
86 perspectiveName, client)
87
89
90 (username, password,
91 serviceName, perspectiveName, client) = self._oldcredArgs
92 d = self._cbAuthIdentity(root, username, password)
93 d.addCallback(self._cbGetPerspective,
94 serviceName, perspectiveName, client)
95 d.addCallbacks(self.gotPerspective, self.failedToGetPerspective)
96
97
98
99
101 raise RuntimeError, "login is one-shot: use startLogin instead"
102
104 self._credentials = credentials
105 self._client = client
106 self._doingLogin = True
107
113
114
115
116
118 """The remote avatar or perspective (obtained each time this factory
119 connects) is now available."""
120 pass
121
123 """The remote root object (obtained each time this factory connects)
124 is now available. This method will be called each time the connection
125 is established and the object reference is retrieved."""
126 pass
127
129 """The login process failed, most likely because of an authorization
130 failure (bad password), but it is also possible that we lost the new
131 connection before we managed to send our credentials.
132 """
133 log.msg("ReconnectingPBClientFactory.failedToGetPerspective")
134 if why.check(pb.PBConnectionLost):
135 log.msg("we lost the brand-new connection")
136
137 return
138
139 self.stopTrying()
140 log.err(why)
141