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1 | 821d9e43 | Michael Hanselmann | #
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2 | 821d9e43 | Michael Hanselmann | #
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3 | 821d9e43 | Michael Hanselmann | |
4 | 821d9e43 | Michael Hanselmann | # Copyright (C) 2006, 2007, 2008 Google Inc.
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5 | 821d9e43 | Michael Hanselmann | #
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6 | 821d9e43 | Michael Hanselmann | # This program is free software; you can redistribute it and/or modify
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7 | 821d9e43 | Michael Hanselmann | # it under the terms of the GNU General Public License as published by
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8 | 821d9e43 | Michael Hanselmann | # the Free Software Foundation; either version 2 of the License, or
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9 | 821d9e43 | Michael Hanselmann | # (at your option) any later version.
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10 | 821d9e43 | Michael Hanselmann | #
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11 | 821d9e43 | Michael Hanselmann | # This program is distributed in the hope that it will be useful, but
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12 | 821d9e43 | Michael Hanselmann | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | 821d9e43 | Michael Hanselmann | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | 821d9e43 | Michael Hanselmann | # General Public License for more details.
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15 | 821d9e43 | Michael Hanselmann | #
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16 | 821d9e43 | Michael Hanselmann | # You should have received a copy of the GNU General Public License
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17 | 821d9e43 | Michael Hanselmann | # along with this program; if not, write to the Free Software
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18 | 821d9e43 | Michael Hanselmann | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | 821d9e43 | Michael Hanselmann | # 02110-1301, USA.
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20 | 821d9e43 | Michael Hanselmann | |
21 | 821d9e43 | Michael Hanselmann | |
22 | 821d9e43 | Michael Hanselmann | """Module with helper classes and functions for daemons"""
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23 | 821d9e43 | Michael Hanselmann | |
24 | 821d9e43 | Michael Hanselmann | |
25 | 112d240d | Guido Trotter | import asyncore |
26 | b66ab629 | Guido Trotter | import asynchat |
27 | 743b53d4 | René Nussbaumer | import grp |
28 | 3b1b0cb6 | Guido Trotter | import os |
29 | 743b53d4 | René Nussbaumer | import pwd |
30 | 821d9e43 | Michael Hanselmann | import signal |
31 | 04ccf5e9 | Guido Trotter | import logging |
32 | a02b89cf | Guido Trotter | import sched |
33 | a02b89cf | Guido Trotter | import time |
34 | 5f3269fc | Guido Trotter | import socket |
35 | 6ddf5c8f | Guido Trotter | import select |
36 | c124045f | Iustin Pop | import sys |
37 | 821d9e43 | Michael Hanselmann | |
38 | 821d9e43 | Michael Hanselmann | from ganeti import utils |
39 | 04ccf5e9 | Guido Trotter | from ganeti import constants |
40 | a02b89cf | Guido Trotter | from ganeti import errors |
41 | a02b89cf | Guido Trotter | |
42 | a02b89cf | Guido Trotter | |
43 | 743b53d4 | René Nussbaumer | _DEFAULT_RUN_USER = "root"
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44 | 743b53d4 | René Nussbaumer | _DEFAULT_RUN_GROUP = "root"
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45 | 743b53d4 | René Nussbaumer | |
46 | 743b53d4 | René Nussbaumer | |
47 | a02b89cf | Guido Trotter | class SchedulerBreakout(Exception): |
48 | a02b89cf | Guido Trotter | """Exception used to get out of the scheduler loop
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49 | a02b89cf | Guido Trotter |
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50 | a02b89cf | Guido Trotter | """
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51 | a02b89cf | Guido Trotter | |
52 | a02b89cf | Guido Trotter | |
53 | a02b89cf | Guido Trotter | def AsyncoreDelayFunction(timeout): |
54 | a02b89cf | Guido Trotter | """Asyncore-compatible scheduler delay function.
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55 | a02b89cf | Guido Trotter |
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56 | a02b89cf | Guido Trotter | This is a delay function for sched that, rather than actually sleeping,
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57 | a02b89cf | Guido Trotter | executes asyncore events happening in the meantime.
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58 | a02b89cf | Guido Trotter |
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59 | a02b89cf | Guido Trotter | After an event has occurred, rather than returning, it raises a
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60 | a02b89cf | Guido Trotter | SchedulerBreakout exception, which will force the current scheduler.run()
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61 | a02b89cf | Guido Trotter | invocation to terminate, so that we can also check for signals. The main loop
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62 | a02b89cf | Guido Trotter | will then call the scheduler run again, which will allow it to actually
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63 | a02b89cf | Guido Trotter | process any due events.
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64 | a02b89cf | Guido Trotter |
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65 | a02b89cf | Guido Trotter | This is needed because scheduler.run() doesn't support a count=..., as
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66 | a02b89cf | Guido Trotter | asyncore loop, and the scheduler module documents throwing exceptions from
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67 | a02b89cf | Guido Trotter | inside the delay function as an allowed usage model.
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68 | a02b89cf | Guido Trotter |
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69 | a02b89cf | Guido Trotter | """
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70 | a02b89cf | Guido Trotter | asyncore.loop(timeout=timeout, count=1, use_poll=True) |
71 | a02b89cf | Guido Trotter | raise SchedulerBreakout()
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72 | a02b89cf | Guido Trotter | |
73 | a02b89cf | Guido Trotter | |
74 | a02b89cf | Guido Trotter | class AsyncoreScheduler(sched.scheduler): |
75 | a02b89cf | Guido Trotter | """Event scheduler integrated with asyncore
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76 | a02b89cf | Guido Trotter |
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77 | a02b89cf | Guido Trotter | """
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78 | a02b89cf | Guido Trotter | def __init__(self, timefunc): |
79 | a02b89cf | Guido Trotter | sched.scheduler.__init__(self, timefunc, AsyncoreDelayFunction)
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80 | 821d9e43 | Michael Hanselmann | |
81 | 821d9e43 | Michael Hanselmann | |
82 | b11780bb | Guido Trotter | class GanetiBaseAsyncoreDispatcher(asyncore.dispatcher): |
83 | b11780bb | Guido Trotter | """Base Ganeti Asyncore Dispacher
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84 | b11780bb | Guido Trotter |
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85 | b11780bb | Guido Trotter | """
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86 | b11780bb | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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87 | b11780bb | Guido Trotter | def handle_error(self): |
88 | b11780bb | Guido Trotter | """Log an error in handling any request, and proceed.
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89 | b11780bb | Guido Trotter |
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90 | b11780bb | Guido Trotter | """
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91 | b11780bb | Guido Trotter | logging.exception("Error while handling asyncore request")
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92 | b11780bb | Guido Trotter | |
93 | b11780bb | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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94 | b11780bb | Guido Trotter | def writable(self): |
95 | b11780bb | Guido Trotter | """Most of the time we don't want to check for writability.
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96 | b11780bb | Guido Trotter |
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97 | b11780bb | Guido Trotter | """
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98 | b11780bb | Guido Trotter | return False |
99 | b11780bb | Guido Trotter | |
100 | b11780bb | Guido Trotter | |
101 | a4b605ae | Guido Trotter | def FormatAddress(family, address): |
102 | a4b605ae | Guido Trotter | """Format a client's address
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103 | a4b605ae | Guido Trotter |
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104 | a4b605ae | Guido Trotter | @type family: integer
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105 | a4b605ae | Guido Trotter | @param family: socket family (one of socket.AF_*)
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106 | a4b605ae | Guido Trotter | @type address: family specific (usually tuple)
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107 | a4b605ae | Guido Trotter | @param address: address, as reported by this class
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108 | a4b605ae | Guido Trotter |
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109 | a4b605ae | Guido Trotter | """
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110 | a4b605ae | Guido Trotter | if family == socket.AF_INET and len(address) == 2: |
111 | a4b605ae | Guido Trotter | return "%s:%d" % address |
112 | a4b605ae | Guido Trotter | elif family == socket.AF_UNIX and len(address) == 3: |
113 | a4b605ae | Guido Trotter | return "pid=%s, uid=%s, gid=%s" % address |
114 | a4b605ae | Guido Trotter | else:
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115 | a4b605ae | Guido Trotter | return str(address) |
116 | a4b605ae | Guido Trotter | |
117 | a4b605ae | Guido Trotter | |
118 | a4b605ae | Guido Trotter | class AsyncStreamServer(GanetiBaseAsyncoreDispatcher): |
119 | a4b605ae | Guido Trotter | """A stream server to use with asyncore.
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120 | a4b605ae | Guido Trotter |
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121 | a4b605ae | Guido Trotter | Each request is accepted, and then dispatched to a separate asyncore
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122 | a4b605ae | Guido Trotter | dispatcher to handle.
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123 | a4b605ae | Guido Trotter |
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124 | a4b605ae | Guido Trotter | """
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125 | a4b605ae | Guido Trotter | |
126 | a4b605ae | Guido Trotter | _REQUEST_QUEUE_SIZE = 5
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127 | a4b605ae | Guido Trotter | |
128 | a4b605ae | Guido Trotter | def __init__(self, family, address): |
129 | a4b605ae | Guido Trotter | """Constructor for AsyncUnixStreamSocket
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130 | a4b605ae | Guido Trotter |
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131 | a4b605ae | Guido Trotter | @type family: integer
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132 | a4b605ae | Guido Trotter | @param family: socket family (one of socket.AF_*)
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133 | a4b605ae | Guido Trotter | @type address: address family dependent
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134 | a4b605ae | Guido Trotter | @param address: address to bind the socket to
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135 | a4b605ae | Guido Trotter |
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136 | a4b605ae | Guido Trotter | """
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137 | a4b605ae | Guido Trotter | GanetiBaseAsyncoreDispatcher.__init__(self)
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138 | a4b605ae | Guido Trotter | self.family = family
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139 | a4b605ae | Guido Trotter | self.create_socket(self.family, socket.SOCK_STREAM) |
140 | a4b605ae | Guido Trotter | self.set_reuse_addr()
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141 | a4b605ae | Guido Trotter | self.bind(address)
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142 | a4b605ae | Guido Trotter | self.listen(self._REQUEST_QUEUE_SIZE) |
143 | a4b605ae | Guido Trotter | |
144 | a4b605ae | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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145 | a4b605ae | Guido Trotter | def handle_accept(self): |
146 | a4b605ae | Guido Trotter | """Accept a new client connection.
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147 | a4b605ae | Guido Trotter |
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148 | a4b605ae | Guido Trotter | Creates a new instance of the handler class, which will use asyncore to
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149 | a4b605ae | Guido Trotter | serve the client.
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150 | a4b605ae | Guido Trotter |
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151 | a4b605ae | Guido Trotter | """
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152 | a4b605ae | Guido Trotter | accept_result = utils.IgnoreSignals(self.accept)
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153 | a4b605ae | Guido Trotter | if accept_result is not None: |
154 | a4b605ae | Guido Trotter | connected_socket, client_address = accept_result |
155 | a4b605ae | Guido Trotter | if self.family == socket.AF_UNIX: |
156 | a4b605ae | Guido Trotter | # override the client address, as for unix sockets nothing meaningful
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157 | a4b605ae | Guido Trotter | # is passed in from accept anyway
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158 | a4b605ae | Guido Trotter | client_address = utils.GetSocketCredentials(connected_socket) |
159 | a4b605ae | Guido Trotter | logging.info("Accepted connection from %s",
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160 | a4b605ae | Guido Trotter | FormatAddress(self.family, client_address))
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161 | a4b605ae | Guido Trotter | self.handle_connection(connected_socket, client_address)
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162 | a4b605ae | Guido Trotter | |
163 | a4b605ae | Guido Trotter | def handle_connection(self, connected_socket, client_address): |
164 | a4b605ae | Guido Trotter | """Handle an already accepted connection.
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165 | a4b605ae | Guido Trotter |
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166 | a4b605ae | Guido Trotter | """
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167 | a4b605ae | Guido Trotter | raise NotImplementedError |
168 | a4b605ae | Guido Trotter | |
169 | a4b605ae | Guido Trotter | |
170 | b66ab629 | Guido Trotter | class AsyncTerminatedMessageStream(asynchat.async_chat): |
171 | b66ab629 | Guido Trotter | """A terminator separated message stream asyncore module.
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172 | b66ab629 | Guido Trotter |
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173 | b66ab629 | Guido Trotter | Handles a stream connection receiving messages terminated by a defined
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174 | b66ab629 | Guido Trotter | separator. For each complete message handle_message is called.
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175 | b66ab629 | Guido Trotter |
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176 | b66ab629 | Guido Trotter | """
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177 | b66ab629 | Guido Trotter | def __init__(self, connected_socket, peer_address, terminator, family): |
178 | b66ab629 | Guido Trotter | """AsyncTerminatedMessageStream constructor.
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179 | b66ab629 | Guido Trotter |
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180 | b66ab629 | Guido Trotter | @type connected_socket: socket.socket
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181 | b66ab629 | Guido Trotter | @param connected_socket: connected stream socket to receive messages from
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182 | b66ab629 | Guido Trotter | @param peer_address: family-specific peer address
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183 | b66ab629 | Guido Trotter | @type terminator: string
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184 | b66ab629 | Guido Trotter | @param terminator: terminator separating messages in the stream
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185 | b66ab629 | Guido Trotter | @type family: integer
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186 | b66ab629 | Guido Trotter | @param family: socket family
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187 | b66ab629 | Guido Trotter |
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188 | b66ab629 | Guido Trotter | """
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189 | b66ab629 | Guido Trotter | # python 2.4/2.5 uses conn=... while 2.6 has sock=... we have to cheat by
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190 | b66ab629 | Guido Trotter | # using a positional argument rather than a keyword one.
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191 | b66ab629 | Guido Trotter | asynchat.async_chat.__init__(self, connected_socket)
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192 | b66ab629 | Guido Trotter | self.connected_socket = connected_socket
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193 | b66ab629 | Guido Trotter | # on python 2.4 there is no "family" attribute for the socket class
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194 | b66ab629 | Guido Trotter | # FIXME: when we move to python 2.5 or above remove the family parameter
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195 | b66ab629 | Guido Trotter | #self.family = self.connected_socket.family
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196 | b66ab629 | Guido Trotter | self.family = family
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197 | b66ab629 | Guido Trotter | self.peer_address = peer_address
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198 | b66ab629 | Guido Trotter | self.terminator = terminator
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199 | b66ab629 | Guido Trotter | self.set_terminator(terminator)
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200 | b66ab629 | Guido Trotter | self.ibuffer = []
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201 | b66ab629 | Guido Trotter | self.next_incoming_message = 0 |
202 | b66ab629 | Guido Trotter | |
203 | b66ab629 | Guido Trotter | # this method is overriding an asynchat.async_chat method
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204 | b66ab629 | Guido Trotter | def collect_incoming_data(self, data): |
205 | b66ab629 | Guido Trotter | self.ibuffer.append(data)
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206 | b66ab629 | Guido Trotter | |
207 | b66ab629 | Guido Trotter | # this method is overriding an asynchat.async_chat method
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208 | b66ab629 | Guido Trotter | def found_terminator(self): |
209 | b66ab629 | Guido Trotter | message = "".join(self.ibuffer) |
210 | b66ab629 | Guido Trotter | self.ibuffer = []
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211 | b66ab629 | Guido Trotter | message_id = self.next_incoming_message
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212 | b66ab629 | Guido Trotter | self.next_incoming_message += 1 |
213 | b66ab629 | Guido Trotter | self.handle_message(message, message_id)
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214 | b66ab629 | Guido Trotter | |
215 | b66ab629 | Guido Trotter | def handle_message(self, message, message_id): |
216 | b66ab629 | Guido Trotter | """Handle a terminated message.
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217 | b66ab629 | Guido Trotter |
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218 | b66ab629 | Guido Trotter | @type message: string
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219 | b66ab629 | Guido Trotter | @param message: message to handle
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220 | b66ab629 | Guido Trotter | @type message_id: integer
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221 | b66ab629 | Guido Trotter | @param message_id: stream's message sequence number
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222 | b66ab629 | Guido Trotter |
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223 | b66ab629 | Guido Trotter | """
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224 | b66ab629 | Guido Trotter | pass
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225 | b66ab629 | Guido Trotter | # TODO: move this method to raise NotImplementedError
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226 | b66ab629 | Guido Trotter | # raise NotImplementedError
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227 | b66ab629 | Guido Trotter | |
228 | b66ab629 | Guido Trotter | def close_log(self): |
229 | b66ab629 | Guido Trotter | logging.info("Closing connection from %s",
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230 | b66ab629 | Guido Trotter | FormatAddress(self.family, self.peer_address)) |
231 | b66ab629 | Guido Trotter | self.close()
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232 | b66ab629 | Guido Trotter | |
233 | b66ab629 | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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234 | b66ab629 | Guido Trotter | def handle_expt(self): |
235 | b66ab629 | Guido Trotter | self.close_log()
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236 | b66ab629 | Guido Trotter | |
237 | b66ab629 | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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238 | b66ab629 | Guido Trotter | def handle_error(self): |
239 | b66ab629 | Guido Trotter | """Log an error in handling any request, and proceed.
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240 | b66ab629 | Guido Trotter |
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241 | b66ab629 | Guido Trotter | """
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242 | b66ab629 | Guido Trotter | logging.exception("Error while handling asyncore request")
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243 | b66ab629 | Guido Trotter | self.close_log()
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244 | b66ab629 | Guido Trotter | |
245 | b66ab629 | Guido Trotter | |
246 | b11780bb | Guido Trotter | class AsyncUDPSocket(GanetiBaseAsyncoreDispatcher): |
247 | 5f3269fc | Guido Trotter | """An improved asyncore udp socket.
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248 | 5f3269fc | Guido Trotter |
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249 | 5f3269fc | Guido Trotter | """
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250 | 5f3269fc | Guido Trotter | def __init__(self): |
251 | 5f3269fc | Guido Trotter | """Constructor for AsyncUDPSocket
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252 | 5f3269fc | Guido Trotter |
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253 | 5f3269fc | Guido Trotter | """
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254 | b11780bb | Guido Trotter | GanetiBaseAsyncoreDispatcher.__init__(self)
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255 | 5f3269fc | Guido Trotter | self._out_queue = []
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256 | 5f3269fc | Guido Trotter | self.create_socket(socket.AF_INET, socket.SOCK_DGRAM)
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257 | 5f3269fc | Guido Trotter | |
258 | 5f3269fc | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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259 | 5f3269fc | Guido Trotter | def handle_connect(self): |
260 | 5f3269fc | Guido Trotter | # Python thinks that the first udp message from a source qualifies as a
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261 | 5f3269fc | Guido Trotter | # "connect" and further ones are part of the same connection. We beg to
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262 | 5f3269fc | Guido Trotter | # differ and treat all messages equally.
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263 | 5f3269fc | Guido Trotter | pass
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264 | 5f3269fc | Guido Trotter | |
265 | 5f3269fc | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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266 | 5f3269fc | Guido Trotter | def handle_read(self): |
267 | 6e7e58b4 | Guido Trotter | recv_result = utils.IgnoreSignals(self.recvfrom,
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268 | 6e7e58b4 | Guido Trotter | constants.MAX_UDP_DATA_SIZE) |
269 | 6e7e58b4 | Guido Trotter | if recv_result is not None: |
270 | 6e7e58b4 | Guido Trotter | payload, address = recv_result |
271 | 6e7e58b4 | Guido Trotter | ip, port = address |
272 | 6e7e58b4 | Guido Trotter | self.handle_datagram(payload, ip, port)
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273 | 5f3269fc | Guido Trotter | |
274 | 5f3269fc | Guido Trotter | def handle_datagram(self, payload, ip, port): |
275 | 5f3269fc | Guido Trotter | """Handle an already read udp datagram
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276 | 5f3269fc | Guido Trotter |
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277 | 5f3269fc | Guido Trotter | """
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278 | 5f3269fc | Guido Trotter | raise NotImplementedError |
279 | 5f3269fc | Guido Trotter | |
280 | 5f3269fc | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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281 | 5f3269fc | Guido Trotter | def writable(self): |
282 | 5f3269fc | Guido Trotter | # We should check whether we can write to the socket only if we have
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283 | 5f3269fc | Guido Trotter | # something scheduled to be written
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284 | 5f3269fc | Guido Trotter | return bool(self._out_queue) |
285 | 5f3269fc | Guido Trotter | |
286 | 48bf6352 | Guido Trotter | # this method is overriding an asyncore.dispatcher method
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287 | 5f3269fc | Guido Trotter | def handle_write(self): |
288 | 3660fcf5 | Guido Trotter | if not self._out_queue: |
289 | 3660fcf5 | Guido Trotter | logging.error("handle_write called with empty output queue")
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290 | 3660fcf5 | Guido Trotter | return
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291 | 3660fcf5 | Guido Trotter | (ip, port, payload) = self._out_queue[0] |
292 | 232144d0 | Guido Trotter | utils.IgnoreSignals(self.sendto, payload, 0, (ip, port)) |
293 | 3660fcf5 | Guido Trotter | self._out_queue.pop(0) |
294 | 3660fcf5 | Guido Trotter | |
295 | 5f3269fc | Guido Trotter | def enqueue_send(self, ip, port, payload): |
296 | 5f3269fc | Guido Trotter | """Enqueue a datagram to be sent when possible
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297 | 5f3269fc | Guido Trotter |
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298 | 5f3269fc | Guido Trotter | """
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299 | c8eded0b | Guido Trotter | if len(payload) > constants.MAX_UDP_DATA_SIZE: |
300 | c8eded0b | Guido Trotter | raise errors.UdpDataSizeError('Packet too big: %s > %s' % (len(payload), |
301 | c8eded0b | Guido Trotter | constants.MAX_UDP_DATA_SIZE)) |
302 | 5f3269fc | Guido Trotter | self._out_queue.append((ip, port, payload))
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303 | 5f3269fc | Guido Trotter | |
304 | 6ddf5c8f | Guido Trotter | def process_next_packet(self, timeout=0): |
305 | 6ddf5c8f | Guido Trotter | """Process the next datagram, waiting for it if necessary.
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306 | 6ddf5c8f | Guido Trotter |
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307 | 6ddf5c8f | Guido Trotter | @type timeout: float
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308 | 6ddf5c8f | Guido Trotter | @param timeout: how long to wait for data
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309 | 6ddf5c8f | Guido Trotter | @rtype: boolean
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310 | 6ddf5c8f | Guido Trotter | @return: True if some data has been handled, False otherwise
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311 | 6ddf5c8f | Guido Trotter |
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312 | 6ddf5c8f | Guido Trotter | """
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313 | 1b429e2a | Iustin Pop | result = utils.WaitForFdCondition(self, select.POLLIN, timeout)
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314 | 1b429e2a | Iustin Pop | if result is not None and result & select.POLLIN: |
315 | 3660fcf5 | Guido Trotter | self.handle_read()
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316 | 6ddf5c8f | Guido Trotter | return True |
317 | 6ddf5c8f | Guido Trotter | else:
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318 | 6ddf5c8f | Guido Trotter | return False |
319 | 6ddf5c8f | Guido Trotter | |
320 | 5f3269fc | Guido Trotter | |
321 | 495ba852 | Guido Trotter | class AsyncAwaker(GanetiBaseAsyncoreDispatcher): |
322 | 495ba852 | Guido Trotter | """A way to notify the asyncore loop that something is going on.
|
323 | 495ba852 | Guido Trotter |
|
324 | 495ba852 | Guido Trotter | If an asyncore daemon is multithreaded when a thread tries to push some data
|
325 | 495ba852 | Guido Trotter | to a socket, the main loop handling asynchronous requests might be sleeping
|
326 | 495ba852 | Guido Trotter | waiting on a select(). To avoid this it can create an instance of the
|
327 | 495ba852 | Guido Trotter | AsyncAwaker, which other threads can use to wake it up.
|
328 | 495ba852 | Guido Trotter |
|
329 | 495ba852 | Guido Trotter | """
|
330 | 495ba852 | Guido Trotter | def __init__(self, signal_fn=None): |
331 | 495ba852 | Guido Trotter | """Constructor for AsyncAwaker
|
332 | 495ba852 | Guido Trotter |
|
333 | 495ba852 | Guido Trotter | @type signal_fn: function
|
334 | 495ba852 | Guido Trotter | @param signal_fn: function to call when awaken
|
335 | 495ba852 | Guido Trotter |
|
336 | 495ba852 | Guido Trotter | """
|
337 | 495ba852 | Guido Trotter | GanetiBaseAsyncoreDispatcher.__init__(self)
|
338 | 495ba852 | Guido Trotter | assert signal_fn == None or callable(signal_fn) |
339 | 495ba852 | Guido Trotter | (self.in_socket, self.out_socket) = socket.socketpair(socket.AF_UNIX, |
340 | 495ba852 | Guido Trotter | socket.SOCK_STREAM) |
341 | 495ba852 | Guido Trotter | self.in_socket.setblocking(0) |
342 | 495ba852 | Guido Trotter | self.set_socket(self.in_socket) |
343 | 495ba852 | Guido Trotter | self.need_signal = True |
344 | 495ba852 | Guido Trotter | self.signal_fn = signal_fn
|
345 | 495ba852 | Guido Trotter | self.connected = True |
346 | 495ba852 | Guido Trotter | |
347 | 495ba852 | Guido Trotter | # this method is overriding an asyncore.dispatcher method
|
348 | 495ba852 | Guido Trotter | def handle_read(self): |
349 | 495ba852 | Guido Trotter | utils.IgnoreSignals(self.recv, 4096) |
350 | 495ba852 | Guido Trotter | if self.signal_fn: |
351 | 495ba852 | Guido Trotter | self.signal_fn()
|
352 | 495ba852 | Guido Trotter | self.need_signal = True |
353 | 495ba852 | Guido Trotter | |
354 | 495ba852 | Guido Trotter | # this method is overriding an asyncore.dispatcher method
|
355 | 495ba852 | Guido Trotter | def close(self): |
356 | 495ba852 | Guido Trotter | asyncore.dispatcher.close(self)
|
357 | 495ba852 | Guido Trotter | self.out_socket.close()
|
358 | 495ba852 | Guido Trotter | |
359 | 495ba852 | Guido Trotter | def signal(self): |
360 | 495ba852 | Guido Trotter | """Signal the asyncore main loop.
|
361 | 495ba852 | Guido Trotter |
|
362 | 495ba852 | Guido Trotter | Any data we send here will be ignored, but it will cause the select() call
|
363 | 495ba852 | Guido Trotter | to return.
|
364 | 495ba852 | Guido Trotter |
|
365 | 495ba852 | Guido Trotter | """
|
366 | 495ba852 | Guido Trotter | # Yes, there is a race condition here. No, we don't care, at worst we're
|
367 | 495ba852 | Guido Trotter | # sending more than one wakeup token, which doesn't harm at all.
|
368 | 495ba852 | Guido Trotter | if self.need_signal: |
369 | 495ba852 | Guido Trotter | self.need_signal = False |
370 | 495ba852 | Guido Trotter | self.out_socket.send("\0") |
371 | 495ba852 | Guido Trotter | |
372 | 495ba852 | Guido Trotter | |
373 | 821d9e43 | Michael Hanselmann | class Mainloop(object): |
374 | 821d9e43 | Michael Hanselmann | """Generic mainloop for daemons
|
375 | 821d9e43 | Michael Hanselmann |
|
376 | 69b99987 | Michael Hanselmann | @ivar scheduler: A sched.scheduler object, which can be used to register
|
377 | 69b99987 | Michael Hanselmann | timed events
|
378 | 69b99987 | Michael Hanselmann |
|
379 | 821d9e43 | Michael Hanselmann | """
|
380 | 821d9e43 | Michael Hanselmann | def __init__(self): |
381 | b14b975f | Michael Hanselmann | """Constructs a new Mainloop instance.
|
382 | b14b975f | Michael Hanselmann |
|
383 | b14b975f | Michael Hanselmann | """
|
384 | 821d9e43 | Michael Hanselmann | self._signal_wait = []
|
385 | a02b89cf | Guido Trotter | self.scheduler = AsyncoreScheduler(time.time)
|
386 | 821d9e43 | Michael Hanselmann | |
387 | 9b739173 | Guido Trotter | @utils.SignalHandled([signal.SIGCHLD])
|
388 | 9b739173 | Guido Trotter | @utils.SignalHandled([signal.SIGTERM])
|
389 | f59dce3e | Guido Trotter | @utils.SignalHandled([signal.SIGINT])
|
390 | 69b99987 | Michael Hanselmann | def Run(self, signal_handlers=None): |
391 | b14b975f | Michael Hanselmann | """Runs the mainloop.
|
392 | b14b975f | Michael Hanselmann |
|
393 | 9b739173 | Guido Trotter | @type signal_handlers: dict
|
394 | 9b739173 | Guido Trotter | @param signal_handlers: signal->L{utils.SignalHandler} passed by decorator
|
395 | b14b975f | Michael Hanselmann |
|
396 | b14b975f | Michael Hanselmann | """
|
397 | 9b739173 | Guido Trotter | assert isinstance(signal_handlers, dict) and \ |
398 | 9b739173 | Guido Trotter | len(signal_handlers) > 0, \ |
399 | 9b739173 | Guido Trotter | "Broken SignalHandled decorator"
|
400 | 9b739173 | Guido Trotter | running = True
|
401 | 9b739173 | Guido Trotter | # Start actual main loop
|
402 | 9b739173 | Guido Trotter | while running:
|
403 | a02b89cf | Guido Trotter | if not self.scheduler.empty(): |
404 | a02b89cf | Guido Trotter | try:
|
405 | a02b89cf | Guido Trotter | self.scheduler.run()
|
406 | a02b89cf | Guido Trotter | except SchedulerBreakout:
|
407 | a02b89cf | Guido Trotter | pass
|
408 | a02b89cf | Guido Trotter | else:
|
409 | a02b89cf | Guido Trotter | asyncore.loop(count=1, use_poll=True) |
410 | 9b739173 | Guido Trotter | |
411 | 9b739173 | Guido Trotter | # Check whether a signal was raised
|
412 | 9b739173 | Guido Trotter | for sig in signal_handlers: |
413 | 9b739173 | Guido Trotter | handler = signal_handlers[sig] |
414 | 9b739173 | Guido Trotter | if handler.called:
|
415 | 9b739173 | Guido Trotter | self._CallSignalWaiters(sig)
|
416 | f59dce3e | Guido Trotter | running = sig not in (signal.SIGTERM, signal.SIGINT) |
417 | 9b739173 | Guido Trotter | handler.Clear() |
418 | a570e2a8 | Guido Trotter | |
419 | b14b975f | Michael Hanselmann | def _CallSignalWaiters(self, signum): |
420 | b14b975f | Michael Hanselmann | """Calls all signal waiters for a certain signal.
|
421 | b14b975f | Michael Hanselmann |
|
422 | b14b975f | Michael Hanselmann | @type signum: int
|
423 | b14b975f | Michael Hanselmann | @param signum: Signal number
|
424 | b14b975f | Michael Hanselmann |
|
425 | b14b975f | Michael Hanselmann | """
|
426 | b14b975f | Michael Hanselmann | for owner in self._signal_wait: |
427 | a9fe7232 | Guido Trotter | owner.OnSignal(signum) |
428 | 821d9e43 | Michael Hanselmann | |
429 | 821d9e43 | Michael Hanselmann | def RegisterSignal(self, owner): |
430 | 821d9e43 | Michael Hanselmann | """Registers a receiver for signal notifications
|
431 | 821d9e43 | Michael Hanselmann |
|
432 | 821d9e43 | Michael Hanselmann | The receiver must support a "OnSignal(self, signum)" function.
|
433 | 821d9e43 | Michael Hanselmann |
|
434 | 821d9e43 | Michael Hanselmann | @type owner: instance
|
435 | 821d9e43 | Michael Hanselmann | @param owner: Receiver
|
436 | 821d9e43 | Michael Hanselmann |
|
437 | 821d9e43 | Michael Hanselmann | """
|
438 | 821d9e43 | Michael Hanselmann | self._signal_wait.append(owner)
|
439 | b11c9e5c | Michael Hanselmann | |
440 | 04ccf5e9 | Guido Trotter | |
441 | 30dabd03 | Michael Hanselmann | def GenericMain(daemon_name, optionparser, dirs, check_fn, exec_fn, |
442 | 1c54156d | Luca Bigliardi | multithreaded=False, console_logging=False, |
443 | 743b53d4 | René Nussbaumer | default_ssl_cert=None, default_ssl_key=None, |
444 | 743b53d4 | René Nussbaumer | user=_DEFAULT_RUN_USER, group=_DEFAULT_RUN_GROUP): |
445 | 04ccf5e9 | Guido Trotter | """Shared main function for daemons.
|
446 | 04ccf5e9 | Guido Trotter |
|
447 | 04ccf5e9 | Guido Trotter | @type daemon_name: string
|
448 | 04ccf5e9 | Guido Trotter | @param daemon_name: daemon name
|
449 | 69b99987 | Michael Hanselmann | @type optionparser: optparse.OptionParser
|
450 | 04ccf5e9 | Guido Trotter | @param optionparser: initialized optionparser with daemon-specific options
|
451 | 04ccf5e9 | Guido Trotter | (common -f -d options will be handled by this module)
|
452 | 5a062513 | Guido Trotter | @type dirs: list of (string, integer)
|
453 | 5a062513 | Guido Trotter | @param dirs: list of directories that must be created if they don't exist,
|
454 | 5a062513 | Guido Trotter | and the permissions to be used to create them
|
455 | 04ccf5e9 | Guido Trotter | @type check_fn: function which accepts (options, args)
|
456 | 04ccf5e9 | Guido Trotter | @param check_fn: function that checks start conditions and exits if they're
|
457 | 04ccf5e9 | Guido Trotter | not met
|
458 | 04ccf5e9 | Guido Trotter | @type exec_fn: function which accepts (options, args)
|
459 | 04ccf5e9 | Guido Trotter | @param exec_fn: function that's executed with the daemon's pid file held, and
|
460 | 04ccf5e9 | Guido Trotter | runs the daemon itself.
|
461 | 30dabd03 | Michael Hanselmann | @type multithreaded: bool
|
462 | 30dabd03 | Michael Hanselmann | @param multithreaded: Whether the daemon uses threads
|
463 | ff917534 | Luca Bigliardi | @type console_logging: boolean
|
464 | ff917534 | Luca Bigliardi | @param console_logging: if True, the daemon will fall back to the system
|
465 | ff917534 | Luca Bigliardi | console if logging fails
|
466 | 0648750e | Michael Hanselmann | @type default_ssl_cert: string
|
467 | 0648750e | Michael Hanselmann | @param default_ssl_cert: Default SSL certificate path
|
468 | 0648750e | Michael Hanselmann | @type default_ssl_key: string
|
469 | 0648750e | Michael Hanselmann | @param default_ssl_key: Default SSL key path
|
470 | 743b53d4 | René Nussbaumer | @param user: Default user to run as
|
471 | 743b53d4 | René Nussbaumer | @type user: string
|
472 | 743b53d4 | René Nussbaumer | @param group: Default group to run as
|
473 | 743b53d4 | René Nussbaumer | @type group: string
|
474 | 04ccf5e9 | Guido Trotter |
|
475 | 04ccf5e9 | Guido Trotter | """
|
476 | 04ccf5e9 | Guido Trotter | optionparser.add_option("-f", "--foreground", dest="fork", |
477 | 04ccf5e9 | Guido Trotter | help="Don't detach from the current terminal",
|
478 | 04ccf5e9 | Guido Trotter | default=True, action="store_false") |
479 | 04ccf5e9 | Guido Trotter | optionparser.add_option("-d", "--debug", dest="debug", |
480 | 04ccf5e9 | Guido Trotter | help="Enable some debug messages",
|
481 | 04ccf5e9 | Guido Trotter | default=False, action="store_true") |
482 | 551b6283 | Iustin Pop | optionparser.add_option("--syslog", dest="syslog", |
483 | 551b6283 | Iustin Pop | help="Enable logging to syslog (except debug"
|
484 | 551b6283 | Iustin Pop | " messages); one of 'no', 'yes' or 'only' [%s]" %
|
485 | 551b6283 | Iustin Pop | constants.SYSLOG_USAGE, |
486 | 551b6283 | Iustin Pop | default=constants.SYSLOG_USAGE, |
487 | 551b6283 | Iustin Pop | choices=["no", "yes", "only"]) |
488 | 0a71aa17 | Michael Hanselmann | |
489 | 04ccf5e9 | Guido Trotter | if daemon_name in constants.DAEMONS_PORTS: |
490 | 0a71aa17 | Michael Hanselmann | default_bind_address = "0.0.0.0"
|
491 | 0a71aa17 | Michael Hanselmann | default_port = utils.GetDaemonPort(daemon_name) |
492 | 0a71aa17 | Michael Hanselmann | |
493 | 0a71aa17 | Michael Hanselmann | # For networked daemons we allow choosing the port and bind address
|
494 | 04ccf5e9 | Guido Trotter | optionparser.add_option("-p", "--port", dest="port", |
495 | 0a71aa17 | Michael Hanselmann | help="Network port (default: %s)" % default_port,
|
496 | 0a71aa17 | Michael Hanselmann | default=default_port, type="int")
|
497 | 04ccf5e9 | Guido Trotter | optionparser.add_option("-b", "--bind", dest="bind_address", |
498 | 0a71aa17 | Michael Hanselmann | help=("Bind address (default: %s)" %
|
499 | 0a71aa17 | Michael Hanselmann | default_bind_address), |
500 | 0a71aa17 | Michael Hanselmann | default=default_bind_address, metavar="ADDRESS")
|
501 | 04ccf5e9 | Guido Trotter | |
502 | 0648750e | Michael Hanselmann | if default_ssl_key is not None and default_ssl_cert is not None: |
503 | 3b1b0cb6 | Guido Trotter | optionparser.add_option("--no-ssl", dest="ssl", |
504 | 3b1b0cb6 | Guido Trotter | help="Do not secure HTTP protocol with SSL",
|
505 | 3b1b0cb6 | Guido Trotter | default=True, action="store_false") |
506 | 3b1b0cb6 | Guido Trotter | optionparser.add_option("-K", "--ssl-key", dest="ssl_key", |
507 | 0648750e | Michael Hanselmann | help=("SSL key path (default: %s)" %
|
508 | 0648750e | Michael Hanselmann | default_ssl_key), |
509 | 0648750e | Michael Hanselmann | default=default_ssl_key, type="string",
|
510 | 0648750e | Michael Hanselmann | metavar="SSL_KEY_PATH")
|
511 | 3b1b0cb6 | Guido Trotter | optionparser.add_option("-C", "--ssl-cert", dest="ssl_cert", |
512 | 0648750e | Michael Hanselmann | help=("SSL certificate path (default: %s)" %
|
513 | 0648750e | Michael Hanselmann | default_ssl_cert), |
514 | 0648750e | Michael Hanselmann | default=default_ssl_cert, type="string",
|
515 | 0648750e | Michael Hanselmann | metavar="SSL_CERT_PATH")
|
516 | 3b1b0cb6 | Guido Trotter | |
517 | 30dabd03 | Michael Hanselmann | # Disable the use of fork(2) if the daemon uses threads
|
518 | 30dabd03 | Michael Hanselmann | utils.no_fork = multithreaded |
519 | 04ccf5e9 | Guido Trotter | |
520 | 04ccf5e9 | Guido Trotter | options, args = optionparser.parse_args() |
521 | 04ccf5e9 | Guido Trotter | |
522 | 0648750e | Michael Hanselmann | if getattr(options, "ssl", False): |
523 | 0648750e | Michael Hanselmann | ssl_paths = { |
524 | 0648750e | Michael Hanselmann | "certificate": options.ssl_cert,
|
525 | 0648750e | Michael Hanselmann | "key": options.ssl_key,
|
526 | 0648750e | Michael Hanselmann | } |
527 | 0648750e | Michael Hanselmann | |
528 | 0648750e | Michael Hanselmann | for name, path in ssl_paths.iteritems(): |
529 | 0648750e | Michael Hanselmann | if not os.path.isfile(path): |
530 | 0648750e | Michael Hanselmann | print >> sys.stderr, "SSL %s file '%s' was not found" % (name, path) |
531 | 3b1b0cb6 | Guido Trotter | sys.exit(constants.EXIT_FAILURE) |
532 | 3b1b0cb6 | Guido Trotter | |
533 | 0648750e | Michael Hanselmann | # TODO: By initiating http.HttpSslParams here we would only read the files
|
534 | 0648750e | Michael Hanselmann | # once and have a proper validation (isfile returns False on directories)
|
535 | 0648750e | Michael Hanselmann | # at the same time.
|
536 | 0648750e | Michael Hanselmann | |
537 | 3b1b0cb6 | Guido Trotter | if check_fn is not None: |
538 | 3b1b0cb6 | Guido Trotter | check_fn(options, args) |
539 | 3b1b0cb6 | Guido Trotter | |
540 | 04ccf5e9 | Guido Trotter | utils.EnsureDirs(dirs) |
541 | 04ccf5e9 | Guido Trotter | |
542 | 04ccf5e9 | Guido Trotter | if options.fork:
|
543 | 743b53d4 | René Nussbaumer | try:
|
544 | 743b53d4 | René Nussbaumer | uid = pwd.getpwnam(user).pw_uid |
545 | 743b53d4 | René Nussbaumer | gid = grp.getgrnam(group).gr_gid |
546 | 743b53d4 | René Nussbaumer | except KeyError: |
547 | 743b53d4 | René Nussbaumer | raise errors.ConfigurationError("User or group not existing on system:" |
548 | 743b53d4 | René Nussbaumer | " %s:%s" % (user, group))
|
549 | 04ccf5e9 | Guido Trotter | utils.CloseFDs() |
550 | 743b53d4 | René Nussbaumer | utils.Daemonize(constants.DAEMONS_LOGFILES[daemon_name], uid, gid) |
551 | 04ccf5e9 | Guido Trotter | |
552 | 04ccf5e9 | Guido Trotter | utils.WritePidFile(daemon_name) |
553 | 04ccf5e9 | Guido Trotter | try:
|
554 | 04ccf5e9 | Guido Trotter | utils.SetupLogging(logfile=constants.DAEMONS_LOGFILES[daemon_name], |
555 | 04ccf5e9 | Guido Trotter | debug=options.debug, |
556 | 04ccf5e9 | Guido Trotter | stderr_logging=not options.fork,
|
557 | e7307f08 | Michael Hanselmann | multithreaded=multithreaded, |
558 | 551b6283 | Iustin Pop | program=daemon_name, |
559 | ff917534 | Luca Bigliardi | syslog=options.syslog, |
560 | ff917534 | Luca Bigliardi | console_logging=console_logging) |
561 | 099c52ad | Iustin Pop | logging.info("%s daemon startup", daemon_name)
|
562 | 04ccf5e9 | Guido Trotter | exec_fn(options, args) |
563 | 04ccf5e9 | Guido Trotter | finally:
|
564 | 04ccf5e9 | Guido Trotter | utils.RemovePidFile(daemon_name) |