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1 | c2a03789 | Iustin Pop | #
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2 | c2a03789 | Iustin Pop | #
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3 | c2a03789 | Iustin Pop | |
4 | c2a03789 | Iustin Pop | # Copyright (C) 2006, 2007 Google Inc.
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5 | c2a03789 | Iustin Pop | #
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6 | c2a03789 | Iustin Pop | # This program is free software; you can redistribute it and/or modify
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7 | c2a03789 | Iustin Pop | # it under the terms of the GNU General Public License as published by
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8 | c2a03789 | Iustin Pop | # the Free Software Foundation; either version 2 of the License, or
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9 | c2a03789 | Iustin Pop | # (at your option) any later version.
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10 | c2a03789 | Iustin Pop | #
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11 | c2a03789 | Iustin Pop | # This program is distributed in the hope that it will be useful, but
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12 | c2a03789 | Iustin Pop | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | c2a03789 | Iustin Pop | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | c2a03789 | Iustin Pop | # General Public License for more details.
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15 | c2a03789 | Iustin Pop | #
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16 | c2a03789 | Iustin Pop | # You should have received a copy of the GNU General Public License
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17 | c2a03789 | Iustin Pop | # along with this program; if not, write to the Free Software
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18 | c2a03789 | Iustin Pop | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | c2a03789 | Iustin Pop | # 02110-1301, USA.
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20 | c2a03789 | Iustin Pop | |
21 | c2a03789 | Iustin Pop | |
22 | c2a03789 | Iustin Pop | """Module for the unix socket protocol
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23 | c2a03789 | Iustin Pop |
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24 | c2a03789 | Iustin Pop | This module implements the local unix socket protocl. You only need
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25 | c2a03789 | Iustin Pop | this module and the opcodes module in the client program in order to
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26 | c2a03789 | Iustin Pop | communicate with the master.
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27 | c2a03789 | Iustin Pop |
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28 | c2a03789 | Iustin Pop | The module is also be used by the master daemon.
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29 | c2a03789 | Iustin Pop |
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30 | c2a03789 | Iustin Pop | """
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31 | c2a03789 | Iustin Pop | |
32 | c2a03789 | Iustin Pop | import socket |
33 | c2a03789 | Iustin Pop | import collections |
34 | c2a03789 | Iustin Pop | import simplejson |
35 | c2a03789 | Iustin Pop | import time |
36 | c2a03789 | Iustin Pop | |
37 | c2a03789 | Iustin Pop | from ganeti import opcodes |
38 | ceab32dd | Iustin Pop | from ganeti import constants |
39 | c2a03789 | Iustin Pop | |
40 | c2a03789 | Iustin Pop | |
41 | c2a03789 | Iustin Pop | KEY_REQUEST = 'request'
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42 | c2a03789 | Iustin Pop | KEY_DATA = 'data'
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43 | c2a03789 | Iustin Pop | REQ_SUBMIT = 'submit'
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44 | c2a03789 | Iustin Pop | REQ_ABORT = 'abort'
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45 | c2a03789 | Iustin Pop | REQ_QUERY = 'query'
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46 | c2a03789 | Iustin Pop | |
47 | c2a03789 | Iustin Pop | DEF_CTMO = 10
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48 | c2a03789 | Iustin Pop | DEF_RWTO = 60
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49 | c2a03789 | Iustin Pop | |
50 | c2a03789 | Iustin Pop | |
51 | c2a03789 | Iustin Pop | class ProtocolError(Exception): |
52 | c2a03789 | Iustin Pop | """Denotes an error in the server communication"""
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53 | c2a03789 | Iustin Pop | |
54 | c2a03789 | Iustin Pop | |
55 | c2a03789 | Iustin Pop | class ConnectionClosedError(ProtocolError): |
56 | c2a03789 | Iustin Pop | """Connection closed error"""
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57 | c2a03789 | Iustin Pop | |
58 | c2a03789 | Iustin Pop | |
59 | c2a03789 | Iustin Pop | class TimeoutError(ProtocolError): |
60 | c2a03789 | Iustin Pop | """Operation timeout error"""
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61 | c2a03789 | Iustin Pop | |
62 | c2a03789 | Iustin Pop | |
63 | c2a03789 | Iustin Pop | class EncodingError(ProtocolError): |
64 | c2a03789 | Iustin Pop | """Encoding failure on the sending side"""
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65 | c2a03789 | Iustin Pop | |
66 | c2a03789 | Iustin Pop | |
67 | c2a03789 | Iustin Pop | class DecodingError(ProtocolError): |
68 | c2a03789 | Iustin Pop | """Decoding failure on the receiving side"""
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69 | c2a03789 | Iustin Pop | |
70 | c2a03789 | Iustin Pop | |
71 | c2a03789 | Iustin Pop | def SerializeJob(job): |
72 | c2a03789 | Iustin Pop | """Convert a job description to a string format.
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73 | c2a03789 | Iustin Pop |
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74 | c2a03789 | Iustin Pop | """
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75 | c2a03789 | Iustin Pop | return simplejson.dumps(job.__getstate__())
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76 | c2a03789 | Iustin Pop | |
77 | c2a03789 | Iustin Pop | |
78 | c2a03789 | Iustin Pop | def UnserializeJob(data): |
79 | c2a03789 | Iustin Pop | """Load a job from a string format"""
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80 | c2a03789 | Iustin Pop | try:
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81 | c2a03789 | Iustin Pop | new_data = simplejson.loads(data) |
82 | c2a03789 | Iustin Pop | except Exception, err: |
83 | c2a03789 | Iustin Pop | raise DecodingError("Error while unserializing: %s" % str(err)) |
84 | c2a03789 | Iustin Pop | job = opcodes.Job() |
85 | c2a03789 | Iustin Pop | job.__setstate__(new_data) |
86 | c2a03789 | Iustin Pop | return job
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87 | c2a03789 | Iustin Pop | |
88 | c2a03789 | Iustin Pop | |
89 | c2a03789 | Iustin Pop | class Transport: |
90 | c2a03789 | Iustin Pop | """Low-level transport class.
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91 | c2a03789 | Iustin Pop |
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92 | c2a03789 | Iustin Pop | This is used on the client side.
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93 | c2a03789 | Iustin Pop |
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94 | c2a03789 | Iustin Pop | This could be replace by any other class that provides the same
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95 | c2a03789 | Iustin Pop | semantics to the Client. This means:
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96 | c2a03789 | Iustin Pop | - can send messages and receive messages
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97 | c2a03789 | Iustin Pop | - safe for multithreading
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98 | c2a03789 | Iustin Pop |
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99 | c2a03789 | Iustin Pop | """
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100 | c2a03789 | Iustin Pop | |
101 | c2a03789 | Iustin Pop | def __init__(self, address, timeouts=None, eom=None): |
102 | c2a03789 | Iustin Pop | """Constructor for the Client class.
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103 | c2a03789 | Iustin Pop |
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104 | c2a03789 | Iustin Pop | Arguments:
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105 | c2a03789 | Iustin Pop | - address: a valid address the the used transport class
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106 | c2a03789 | Iustin Pop | - timeout: a list of timeouts, to be used on connect and read/write
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107 | c2a03789 | Iustin Pop | - eom: an identifier to be used as end-of-message which the
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108 | c2a03789 | Iustin Pop | upper-layer will guarantee that this identifier will not appear
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109 | c2a03789 | Iustin Pop | in any message
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110 | c2a03789 | Iustin Pop |
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111 | c2a03789 | Iustin Pop | There are two timeouts used since we might want to wait for a long
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112 | c2a03789 | Iustin Pop | time for a response, but the connect timeout should be lower.
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113 | c2a03789 | Iustin Pop |
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114 | c2a03789 | Iustin Pop | If not passed, we use a default of 10 and respectively 60 seconds.
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115 | c2a03789 | Iustin Pop |
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116 | c2a03789 | Iustin Pop | Note that on reading data, since the timeout applies to an
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117 | c2a03789 | Iustin Pop | invidual receive, it might be that the total duration is longer
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118 | c2a03789 | Iustin Pop | than timeout value passed (we make a hard limit at twice the read
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119 | c2a03789 | Iustin Pop | timeout).
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120 | c2a03789 | Iustin Pop |
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121 | c2a03789 | Iustin Pop | """
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122 | c2a03789 | Iustin Pop | self.address = address
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123 | c2a03789 | Iustin Pop | if timeouts is None: |
124 | c2a03789 | Iustin Pop | self._ctimeout, self._rwtimeout = DEF_CTMO, DEF_RWTO |
125 | c2a03789 | Iustin Pop | else:
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126 | c2a03789 | Iustin Pop | self._ctimeout, self._rwtimeout = timeouts |
127 | c2a03789 | Iustin Pop | |
128 | c2a03789 | Iustin Pop | self.socket = None |
129 | c2a03789 | Iustin Pop | self._buffer = "" |
130 | c2a03789 | Iustin Pop | self._msgs = collections.deque()
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131 | c2a03789 | Iustin Pop | |
132 | c2a03789 | Iustin Pop | if eom is None: |
133 | c2a03789 | Iustin Pop | self.eom = '\3' |
134 | c2a03789 | Iustin Pop | else:
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135 | c2a03789 | Iustin Pop | self.eom = eom
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136 | c2a03789 | Iustin Pop | |
137 | c2a03789 | Iustin Pop | try:
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138 | c2a03789 | Iustin Pop | self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
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139 | c2a03789 | Iustin Pop | self.socket.settimeout(self._ctimeout) |
140 | c2a03789 | Iustin Pop | try:
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141 | c2a03789 | Iustin Pop | self.socket.connect(address)
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142 | c2a03789 | Iustin Pop | except socket.timeout, err:
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143 | c2a03789 | Iustin Pop | raise TimeoutError("Connection timed out: %s" % str(err)) |
144 | c2a03789 | Iustin Pop | self.socket.settimeout(self._rwtimeout) |
145 | c2a03789 | Iustin Pop | except socket.error:
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146 | c2a03789 | Iustin Pop | if self.socket is not None: |
147 | c2a03789 | Iustin Pop | self.socket.close()
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148 | c2a03789 | Iustin Pop | self.socket = None |
149 | c2a03789 | Iustin Pop | raise
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150 | c2a03789 | Iustin Pop | |
151 | c2a03789 | Iustin Pop | def _CheckSocket(self): |
152 | c2a03789 | Iustin Pop | """Make sure we are connected.
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153 | c2a03789 | Iustin Pop |
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154 | c2a03789 | Iustin Pop | """
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155 | c2a03789 | Iustin Pop | if self.socket is None: |
156 | c2a03789 | Iustin Pop | raise ProtocolError("Connection is closed") |
157 | c2a03789 | Iustin Pop | |
158 | c2a03789 | Iustin Pop | def Send(self, msg): |
159 | c2a03789 | Iustin Pop | """Send a message.
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160 | c2a03789 | Iustin Pop |
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161 | c2a03789 | Iustin Pop | This just sends a message and doesn't wait for the response.
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162 | c2a03789 | Iustin Pop |
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163 | c2a03789 | Iustin Pop | """
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164 | c2a03789 | Iustin Pop | if self.eom in msg: |
165 | c2a03789 | Iustin Pop | raise EncodingError("Message terminator found in payload") |
166 | c2a03789 | Iustin Pop | self._CheckSocket()
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167 | c2a03789 | Iustin Pop | try:
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168 | c2a03789 | Iustin Pop | self.socket.sendall(msg + self.eom) |
169 | c2a03789 | Iustin Pop | except socket.timeout, err:
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170 | c2a03789 | Iustin Pop | raise TimeoutError("Sending timeout: %s" % str(err)) |
171 | c2a03789 | Iustin Pop | |
172 | c2a03789 | Iustin Pop | def Recv(self): |
173 | c2a03789 | Iustin Pop | """Try to receive a messae from the socket.
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174 | c2a03789 | Iustin Pop |
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175 | c2a03789 | Iustin Pop | In case we already have messages queued, we just return from the
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176 | c2a03789 | Iustin Pop | queue. Otherwise, we try to read data with a _rwtimeout network
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177 | c2a03789 | Iustin Pop | timeout, and making sure we don't go over 2x_rwtimeout as a global
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178 | c2a03789 | Iustin Pop | limit.
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179 | c2a03789 | Iustin Pop |
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180 | c2a03789 | Iustin Pop | """
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181 | c2a03789 | Iustin Pop | self._CheckSocket()
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182 | c2a03789 | Iustin Pop | etime = time.time() + self._rwtimeout
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183 | c2a03789 | Iustin Pop | while not self._msgs: |
184 | c2a03789 | Iustin Pop | if time.time() > etime:
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185 | c2a03789 | Iustin Pop | raise TimeoutError("Extended receive timeout") |
186 | c2a03789 | Iustin Pop | try:
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187 | c2a03789 | Iustin Pop | data = self.socket.recv(4096) |
188 | c2a03789 | Iustin Pop | except socket.timeout, err:
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189 | c2a03789 | Iustin Pop | raise TimeoutError("Receive timeout: %s" % str(err)) |
190 | c2a03789 | Iustin Pop | if not data: |
191 | c2a03789 | Iustin Pop | raise ConnectionClosedError("Connection closed while reading") |
192 | c2a03789 | Iustin Pop | new_msgs = (self._buffer + data).split(self.eom) |
193 | c2a03789 | Iustin Pop | self._buffer = new_msgs.pop()
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194 | c2a03789 | Iustin Pop | self._msgs.extend(new_msgs)
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195 | c2a03789 | Iustin Pop | return self._msgs.popleft() |
196 | c2a03789 | Iustin Pop | |
197 | c2a03789 | Iustin Pop | def Call(self, msg): |
198 | c2a03789 | Iustin Pop | """Send a message and wait for the response.
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199 | c2a03789 | Iustin Pop |
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200 | c2a03789 | Iustin Pop | This is just a wrapper over Send and Recv.
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201 | c2a03789 | Iustin Pop |
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202 | c2a03789 | Iustin Pop | """
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203 | c2a03789 | Iustin Pop | self.Send(msg)
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204 | c2a03789 | Iustin Pop | return self.Recv() |
205 | c2a03789 | Iustin Pop | |
206 | c2a03789 | Iustin Pop | def Close(self): |
207 | c2a03789 | Iustin Pop | """Close the socket"""
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208 | c2a03789 | Iustin Pop | if self.socket is not None: |
209 | c2a03789 | Iustin Pop | self.socket.close()
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210 | c2a03789 | Iustin Pop | self.socket = None |
211 | c2a03789 | Iustin Pop | |
212 | c2a03789 | Iustin Pop | |
213 | c2a03789 | Iustin Pop | class Client(object): |
214 | c2a03789 | Iustin Pop | """High-level client implementation.
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215 | c2a03789 | Iustin Pop |
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216 | c2a03789 | Iustin Pop | This uses a backing Transport-like class on top of which it
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217 | c2a03789 | Iustin Pop | implements data serialization/deserialization.
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218 | c2a03789 | Iustin Pop |
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219 | c2a03789 | Iustin Pop | """
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220 | ceab32dd | Iustin Pop | def __init__(self, address=None, timeouts=None, transport=Transport): |
221 | c2a03789 | Iustin Pop | """Constructor for the Client class.
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222 | c2a03789 | Iustin Pop |
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223 | c2a03789 | Iustin Pop | Arguments:
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224 | c2a03789 | Iustin Pop | - address: a valid address the the used transport class
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225 | c2a03789 | Iustin Pop | - timeout: a list of timeouts, to be used on connect and read/write
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226 | c2a03789 | Iustin Pop | - transport: a Transport-like class
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227 | c2a03789 | Iustin Pop |
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228 | c2a03789 | Iustin Pop |
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229 | c2a03789 | Iustin Pop | If timeout is not passed, the default timeouts of the transport
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230 | c2a03789 | Iustin Pop | class are used.
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231 | c2a03789 | Iustin Pop |
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232 | c2a03789 | Iustin Pop | """
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233 | ceab32dd | Iustin Pop | if address is None: |
234 | ceab32dd | Iustin Pop | address = constants.MASTER_SOCKET |
235 | c2a03789 | Iustin Pop | self.transport = transport(address, timeouts=timeouts)
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236 | c2a03789 | Iustin Pop | |
237 | c2a03789 | Iustin Pop | def SendRequest(self, request, data): |
238 | c2a03789 | Iustin Pop | """Send a generic request and return the response.
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239 | c2a03789 | Iustin Pop |
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240 | c2a03789 | Iustin Pop | """
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241 | c2a03789 | Iustin Pop | msg = {KEY_REQUEST: request, KEY_DATA: data} |
242 | c2a03789 | Iustin Pop | result = self.transport.Call(simplejson.dumps(msg))
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243 | c2a03789 | Iustin Pop | try:
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244 | c2a03789 | Iustin Pop | data = simplejson.loads(result) |
245 | c2a03789 | Iustin Pop | except Exception, err: |
246 | c2a03789 | Iustin Pop | raise ProtocolError("Error while deserializing response: %s" % str(err)) |
247 | a14a17fc | Iustin Pop | if (not isinstance(data, dict) or |
248 | a14a17fc | Iustin Pop | 'success' not in data or |
249 | a14a17fc | Iustin Pop | 'result' not in data): |
250 | a14a17fc | Iustin Pop | raise DecodingError("Invalid response from server: %s" % str(data)) |
251 | c2a03789 | Iustin Pop | return data
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252 | c2a03789 | Iustin Pop | |
253 | c2a03789 | Iustin Pop | def SubmitJob(self, job): |
254 | c2a03789 | Iustin Pop | """Submit a job"""
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255 | c2a03789 | Iustin Pop | return self.SendRequest(REQ_SUBMIT, SerializeJob(job)) |
256 | c2a03789 | Iustin Pop | |
257 | c2a03789 | Iustin Pop | def Query(self, data): |
258 | c2a03789 | Iustin Pop | """Make a query"""
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259 | c2a03789 | Iustin Pop | return self.SendRequest(REQ_QUERY, data) |