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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
# Copyright (C) 2009 Internet Systems Consortium.
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM
# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
import sys
import socket
import struct
import os
import isc.cc.message
class ProtocolError(Exception): pass
class NetworkError(Exception): pass
class SessionError(Exception): pass
class Session:
def __init__(self, port=0):
self._socket = None
self._lname = None
self._recvbuffer = bytearray()
self._recvlength = 0
self._sequence = 1
self._closed = False
self._queue = []
if port == 0:
if 'ISC_MSGQ_PORT' in os.environ:
port = int(os.environ["ISC_MSGQ_PORT"])
else:
port = 9912
try:
self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self._socket.connect(tuple(['127.0.0.1', port]))
self.sendmsg({ "type": "getlname" })
env, msg = self.recvmsg(False)
if not env:
raise ProtocolError("Could not get local name")
self._lname = msg["lname"]
if not self._lname:
raise ProtocolError("Could not get local name")
except socket.error as se:
raise SessionError(se)
@property
def lname(self):
return self._lname
def close(self):
self._socket.close()
self._lname = None
self._closed = True
def sendmsg(self, env, msg = None):
XXmsg = msg
XXenv = env
if self._closed:
raise SessionError("Session has been closed.")
if type(env) == dict:
env = isc.cc.message.to_wire(env)
if type(msg) == dict:
msg = isc.cc.message.to_wire(msg)
self._socket.setblocking(1)
length = 2 + len(env);
if msg:
length += len(msg)
self._socket.send(struct.pack("!I", length))
self._socket.send(struct.pack("!H", len(env)))
self._socket.send(env)
if msg:
self._socket.send(msg)
def recvmsg(self, nonblock = True, seq = None):
#print("[XX] queue len: " + str(len(self._queue)))
if len(self._queue) > 0:
if seq == None:
#print("[XX] return first")
return self._queue.pop(0)
else:
i = 0;
#print("[XX] check rest")
for env, msg in self._queue:
if "reply" in env and seq == env["reply"]:
return self._queue.pop(i)
else:
i = i + 1
#print("[XX] not found")
if self._closed:
raise SessionError("Session has been closed.")
data = self._receive_full_buffer(nonblock)
if data and len(data) > 2:
header_length = struct.unpack('>H', data[0:2])[0]
data_length = len(data) - 2 - header_length
if data_length > 0:
env = isc.cc.message.from_wire(data[2:header_length+2])
msg = isc.cc.message.from_wire(data[header_length + 2:])
if seq == None or "reply" in env and seq == env["reply"]:
return env, msg
else:
self._queue.append((env,msg))
return self.recvmsg(nonblock, seq)
else:
return isc.cc.message.from_wire(data[2:header_length+2]), None
return None, None
def _receive_full_buffer(self, nonblock):
if nonblock:
self._socket.setblocking(0)
else:
self._socket.setblocking(1)
if self._recvlength == 0:
length = 4
length -= len(self._recvbuffer)
try:
data = self._socket.recv(length)
except:
return None
if data == "": # server closed connection
raise ProtocolError("Read of 0 bytes: connection closed")
self._recvbuffer += data
if len(self._recvbuffer) < 4:
return None
self._recvlength = struct.unpack('>I', self._recvbuffer)[0]
self._recvbuffer = bytearray()
length = self._recvlength - len(self._recvbuffer)
while (length > 0):
try:
data = self._socket.recv(length)
except:
return None
if data == "": # server closed connection
raise ProtocolError("Read of 0 bytes: connection closed")
self._recvbuffer += data
length -= len(data)
data = self._recvbuffer
self._recvbuffer = bytearray()
self._recvlength = 0
return (data)
def _next_sequence(self):
self._sequence += 1
return self._sequence
def group_subscribe(self, group, instance = "*"):
self.sendmsg({
"type": "subscribe",
"group": group,
"instance": instance,
})
def group_unsubscribe(self, group, instance = "*"):
self.sendmsg({
"type": "unsubscribe",
"group": group,
"instance": instance,
})
def group_sendmsg(self, msg, group, instance = "*", to = "*"):
seq = self._next_sequence()
self.sendmsg({
"type": "send",
"from": self._lname,
"to": to,
"group": group,
"instance": instance,
"seq": seq,
}, isc.cc.message.to_wire(msg))
return seq
def group_recvmsg(self, nonblock = True, seq = None):
env, msg = self.recvmsg(nonblock, seq)
if env == None:
# return none twice to match normal return value
# (so caller won't get a type error on no data)
return (None, None)
return (msg, env)
def group_reply(self, routing, msg):
seq = self._next_sequence()
self.sendmsg({
"type": "send",
"from": self._lname,
"to": routing["from"],
"group": routing["group"],
"instance": routing["instance"],
"seq": seq,
"reply": routing["seq"],
}, isc.cc.message.to_wire(msg))
return seq
if __name__ == "__main__":
import doctest
doctest.testmod()
|
