1 | """Generic socket server classes. |
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2 | |
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3 | This module tries to capture the various aspects of defining a server: |
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4 | |
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5 | For socket-based servers: |
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6 | |
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7 | - address family: |
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8 | - AF_INET{,6}: IP (Internet Protocol) sockets (default) |
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9 | - AF_UNIX: Unix domain sockets |
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10 | - others, e.g. AF_DECNET are conceivable (see <socket.h> |
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11 | - socket type: |
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12 | - SOCK_STREAM (reliable stream, e.g. TCP) |
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13 | - SOCK_DGRAM (datagrams, e.g. UDP) |
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14 | |
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15 | For request-based servers (including socket-based): |
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16 | |
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17 | - client address verification before further looking at the request |
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18 | (This is actually a hook for any processing that needs to look |
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19 | at the request before anything else, e.g. logging) |
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20 | - how to handle multiple requests: |
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21 | - synchronous (one request is handled at a time) |
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22 | - forking (each request is handled by a new process) |
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23 | - threading (each request is handled by a new thread) |
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24 | |
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25 | The classes in this module favor the server type that is simplest to |
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26 | write: a synchronous TCP/IP server. This is bad class design, but |
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27 | save some typing. (There's also the issue that a deep class hierarchy |
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28 | slows down method lookups.) |
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29 | |
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30 | There are five classes in an inheritance diagram, four of which represent |
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31 | synchronous servers of four types: |
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32 | |
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33 | +------------+ |
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34 | | BaseServer | |
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35 | +------------+ |
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36 | | |
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37 | v |
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38 | +-----------+ +------------------+ |
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39 | | TCPServer |------->| UnixStreamServer | |
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40 | +-----------+ +------------------+ |
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41 | | |
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42 | v |
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43 | +-----------+ +--------------------+ |
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44 | | UDPServer |------->| UnixDatagramServer | |
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45 | +-----------+ +--------------------+ |
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46 | |
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47 | Note that UnixDatagramServer derives from UDPServer, not from |
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48 | UnixStreamServer -- the only difference between an IP and a Unix |
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49 | stream server is the address family, which is simply repeated in both |
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50 | unix server classes. |
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51 | |
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52 | Forking and threading versions of each type of server can be created |
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53 | using the ForkingMixIn and ThreadingMixIn mix-in classes. For |
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54 | instance, a threading UDP server class is created as follows: |
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55 | |
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56 | class ThreadingUDPServer(ThreadingMixIn, UDPServer): pass |
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57 | |
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58 | The Mix-in class must come first, since it overrides a method defined |
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59 | in UDPServer! Setting the various member variables also changes |
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60 | the behavior of the underlying server mechanism. |
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61 | |
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62 | To implement a service, you must derive a class from |
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63 | BaseRequestHandler and redefine its handle() method. You can then run |
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64 | various versions of the service by combining one of the server classes |
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65 | with your request handler class. |
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66 | |
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67 | The request handler class must be different for datagram or stream |
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68 | services. This can be hidden by using the request handler |
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69 | subclasses StreamRequestHandler or DatagramRequestHandler. |
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70 | |
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71 | Of course, you still have to use your head! |
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72 | |
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73 | For instance, it makes no sense to use a forking server if the service |
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74 | contains state in memory that can be modified by requests (since the |
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75 | modifications in the child process would never reach the initial state |
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76 | kept in the parent process and passed to each child). In this case, |
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77 | you can use a threading server, but you will probably have to use |
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78 | locks to avoid two requests that come in nearly simultaneous to apply |
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79 | conflicting changes to the server state. |
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80 | |
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81 | On the other hand, if you are building e.g. an HTTP server, where all |
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82 | data is stored externally (e.g. in the file system), a synchronous |
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83 | class will essentially render the service "deaf" while one request is |
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84 | being handled -- which may be for a very long time if a client is slow |
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85 | to read all the data it has requested. Here a threading or forking |
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86 | server is appropriate. |
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87 | |
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88 | In some cases, it may be appropriate to process part of a request |
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89 | synchronously, but to finish processing in a forked child depending on |
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90 | the request data. This can be implemented by using a synchronous |
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91 | server and doing an explicit fork in the request handler class |
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92 | handle() method. |
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93 | |
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94 | Another approach to handling multiple simultaneous requests in an |
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95 | environment that supports neither threads nor fork (or where these are |
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96 | too expensive or inappropriate for the service) is to maintain an |
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97 | explicit table of partially finished requests and to use select() to |
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98 | decide which request to work on next (or whether to handle a new |
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99 | incoming request). This is particularly important for stream services |
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100 | where each client can potentially be connected for a long time (if |
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101 | threads or subprocesses cannot be used). |
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102 | |
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103 | Future work: |
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104 | - Standard classes for Sun RPC (which uses either UDP or TCP) |
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105 | - Standard mix-in classes to implement various authentication |
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106 | and encryption schemes |
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107 | - Standard framework for select-based multiplexing |
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108 | |
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109 | XXX Open problems: |
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110 | - What to do with out-of-band data? |
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111 | |
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112 | BaseServer: |
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113 | - split generic "request" functionality out into BaseServer class. |
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114 | Copyright (C) 2000 Luke Kenneth Casson Leighton <lkcl@samba.org> |
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115 | |
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116 | example: read entries from a SQL database (requires overriding |
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117 | get_request() to return a table entry from the database). |
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118 | entry is processed by a RequestHandlerClass. |
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119 | |
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120 | """ |
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121 | |
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122 | # Author of the BaseServer patch: Luke Kenneth Casson Leighton |
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123 | |
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124 | # XXX Warning! |
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125 | # There is a test suite for this module, but it cannot be run by the |
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126 | # standard regression test. |
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127 | # To run it manually, run Lib/test/test_socketserver.py. |
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128 | |
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129 | __version__ = "0.4" |
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130 | |
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131 | |
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132 | import socket |
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133 | import select |
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134 | import sys |
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135 | import os |
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136 | import errno |
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137 | try: |
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138 | import threading |
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139 | except ImportError: |
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140 | import dummy_threading as threading |
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141 | |
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142 | __all__ = ["TCPServer","UDPServer","ForkingUDPServer","ForkingTCPServer", |
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143 | "ThreadingUDPServer","ThreadingTCPServer","BaseRequestHandler", |
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144 | "StreamRequestHandler","DatagramRequestHandler", |
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145 | "ThreadingMixIn", "ForkingMixIn"] |
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146 | if hasattr(socket, "AF_UNIX"): |
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147 | __all__.extend(["UnixStreamServer","UnixDatagramServer", |
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148 | "ThreadingUnixStreamServer", |
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149 | "ThreadingUnixDatagramServer"]) |
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150 | |
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151 | def _eintr_retry(func, *args): |
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152 | """restart a system call interrupted by EINTR""" |
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153 | while True: |
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154 | try: |
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155 | return func(*args) |
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156 | except (OSError, select.error) as e: |
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157 | if e.args[0] != errno.EINTR: |
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158 | raise |
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159 | |
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160 | class BaseServer: |
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161 | |
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162 | """Base class for server classes. |
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163 | |
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164 | Methods for the caller: |
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165 | |
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166 | - __init__(server_address, RequestHandlerClass) |
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167 | - serve_forever(poll_interval=0.5) |
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168 | - shutdown() |
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169 | - handle_request() # if you do not use serve_forever() |
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170 | - fileno() -> int # for select() |
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171 | |
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172 | Methods that may be overridden: |
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173 | |
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174 | - server_bind() |
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175 | - server_activate() |
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176 | - get_request() -> request, client_address |
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177 | - handle_timeout() |
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178 | - verify_request(request, client_address) |
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179 | - server_close() |
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180 | - process_request(request, client_address) |
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181 | - shutdown_request(request) |
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182 | - close_request(request) |
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183 | - handle_error() |
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184 | |
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185 | Methods for derived classes: |
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186 | |
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187 | - finish_request(request, client_address) |
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188 | |
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189 | Class variables that may be overridden by derived classes or |
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190 | instances: |
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191 | |
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192 | - timeout |
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193 | - address_family |
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194 | - socket_type |
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195 | - allow_reuse_address |
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196 | |
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197 | Instance variables: |
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198 | |
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199 | - RequestHandlerClass |
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200 | - socket |
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201 | |
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202 | """ |
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203 | |
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204 | timeout = None |
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205 | |
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206 | def __init__(self, server_address, RequestHandlerClass): |
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207 | """Constructor. May be extended, do not override.""" |
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208 | self.server_address = server_address |
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209 | self.RequestHandlerClass = RequestHandlerClass |
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210 | self.__is_shut_down = threading.Event() |
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211 | self.__shutdown_request = False |
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212 | |
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213 | def server_activate(self): |
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214 | """Called by constructor to activate the server. |
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215 | |
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216 | May be overridden. |
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217 | |
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218 | """ |
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219 | pass |
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220 | |
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221 | def serve_forever(self, poll_interval=0.5): |
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222 | """Handle one request at a time until shutdown. |
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223 | |
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224 | Polls for shutdown every poll_interval seconds. Ignores |
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225 | self.timeout. If you need to do periodic tasks, do them in |
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226 | another thread. |
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227 | """ |
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228 | self.__is_shut_down.clear() |
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229 | try: |
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230 | while not self.__shutdown_request: |
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231 | # XXX: Consider using another file descriptor or |
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232 | # connecting to the socket to wake this up instead of |
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233 | # polling. Polling reduces our responsiveness to a |
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234 | # shutdown request and wastes cpu at all other times. |
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235 | r, w, e = _eintr_retry(select.select, [self], [], [], |
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236 | poll_interval) |
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237 | if self in r: |
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238 | self._handle_request_noblock() |
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239 | finally: |
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240 | self.__shutdown_request = False |
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241 | self.__is_shut_down.set() |
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242 | |
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243 | def shutdown(self): |
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244 | """Stops the serve_forever loop. |
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245 | |
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246 | Blocks until the loop has finished. This must be called while |
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247 | serve_forever() is running in another thread, or it will |
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248 | deadlock. |
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249 | """ |
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250 | self.__shutdown_request = True |
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251 | self.__is_shut_down.wait() |
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252 | |
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253 | # The distinction between handling, getting, processing and |
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254 | # finishing a request is fairly arbitrary. Remember: |
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255 | # |
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256 | # - handle_request() is the top-level call. It calls |
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257 | # select, get_request(), verify_request() and process_request() |
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258 | # - get_request() is different for stream or datagram sockets |
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259 | # - process_request() is the place that may fork a new process |
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260 | # or create a new thread to finish the request |
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261 | # - finish_request() instantiates the request handler class; |
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262 | # this constructor will handle the request all by itself |
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263 | |
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264 | def handle_request(self): |
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265 | """Handle one request, possibly blocking. |
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266 | |
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267 | Respects self.timeout. |
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268 | """ |
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269 | # Support people who used socket.settimeout() to escape |
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270 | # handle_request before self.timeout was available. |
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271 | timeout = self.socket.gettimeout() |
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272 | if timeout is None: |
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273 | timeout = self.timeout |
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274 | elif self.timeout is not None: |
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275 | timeout = min(timeout, self.timeout) |
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276 | fd_sets = _eintr_retry(select.select, [self], [], [], timeout) |
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277 | if not fd_sets[0]: |
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278 | self.handle_timeout() |
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279 | return |
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280 | self._handle_request_noblock() |
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281 | |
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282 | def _handle_request_noblock(self): |
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283 | """Handle one request, without blocking. |
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284 | |
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285 | I assume that select.select has returned that the socket is |
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286 | readable before this function was called, so there should be |
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287 | no risk of blocking in get_request(). |
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288 | """ |
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289 | try: |
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290 | request, client_address = self.get_request() |
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291 | except socket.error: |
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292 | return |
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293 | if self.verify_request(request, client_address): |
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294 | try: |
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295 | self.process_request(request, client_address) |
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296 | except: |
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297 | self.handle_error(request, client_address) |
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298 | self.shutdown_request(request) |
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299 | |
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300 | def handle_timeout(self): |
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301 | """Called if no new request arrives within self.timeout. |
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302 | |
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303 | Overridden by ForkingMixIn. |
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304 | """ |
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305 | pass |
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306 | |
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307 | def verify_request(self, request, client_address): |
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308 | """Verify the request. May be overridden. |
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309 | |
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310 | Return True if we should proceed with this request. |
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311 | |
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312 | """ |
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313 | return True |
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314 | |
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315 | def process_request(self, request, client_address): |
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316 | """Call finish_request. |
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317 | |
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318 | Overridden by ForkingMixIn and ThreadingMixIn. |
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319 | |
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320 | """ |
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321 | self.finish_request(request, client_address) |
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322 | self.shutdown_request(request) |
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323 | |
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324 | def server_close(self): |
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325 | """Called to clean-up the server. |
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326 | |
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327 | May be overridden. |
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328 | |
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329 | """ |
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330 | pass |
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331 | |
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332 | def finish_request(self, request, client_address): |
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333 | """Finish one request by instantiating RequestHandlerClass.""" |
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334 | self.RequestHandlerClass(request, client_address, self) |
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335 | |
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336 | def shutdown_request(self, request): |
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337 | """Called to shutdown and close an individual request.""" |
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338 | self.close_request(request) |
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339 | |
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340 | def close_request(self, request): |
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341 | """Called to clean up an individual request.""" |
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342 | pass |
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343 | |
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344 | def handle_error(self, request, client_address): |
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345 | """Handle an error gracefully. May be overridden. |
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346 | |
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347 | The default is to print a traceback and continue. |
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348 | |
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349 | """ |
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350 | print '-'*40 |
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351 | print 'Exception happened during processing of request from', |
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352 | print client_address |
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353 | import traceback |
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354 | traceback.print_exc() # XXX But this goes to stderr! |
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355 | print '-'*40 |
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356 | |
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357 | |
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358 | class TCPServer(BaseServer): |
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359 | |
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360 | """Base class for various socket-based server classes. |
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361 | |
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362 | Defaults to synchronous IP stream (i.e., TCP). |
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363 | |
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364 | Methods for the caller: |
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365 | |
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366 | - __init__(server_address, RequestHandlerClass, bind_and_activate=True) |
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367 | - serve_forever(poll_interval=0.5) |
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368 | - shutdown() |
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369 | - handle_request() # if you don't use serve_forever() |
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370 | - fileno() -> int # for select() |
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371 | |
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372 | Methods that may be overridden: |
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373 | |
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374 | - server_bind() |
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375 | - server_activate() |
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376 | - get_request() -> request, client_address |
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377 | - handle_timeout() |
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378 | - verify_request(request, client_address) |
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379 | - process_request(request, client_address) |
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380 | - shutdown_request(request) |
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381 | - close_request(request) |
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382 | - handle_error() |
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383 | |
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384 | Methods for derived classes: |
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385 | |
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386 | - finish_request(request, client_address) |
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387 | |
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388 | Class variables that may be overridden by derived classes or |
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389 | instances: |
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390 | |
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391 | - timeout |
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392 | - address_family |
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393 | - socket_type |
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394 | - request_queue_size (only for stream sockets) |
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395 | - allow_reuse_address |
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396 | |
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397 | Instance variables: |
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398 | |
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399 | - server_address |
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400 | - RequestHandlerClass |
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401 | - socket |
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402 | |
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403 | """ |
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404 | |
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405 | address_family = socket.AF_INET |
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406 | |
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407 | socket_type = socket.SOCK_STREAM |
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408 | |
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409 | request_queue_size = 5 |
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410 | |
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411 | allow_reuse_address = False |
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412 | |
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413 | def __init__(self, server_address, RequestHandlerClass, bind_and_activate=True): |
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414 | """Constructor. May be extended, do not override.""" |
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415 | BaseServer.__init__(self, server_address, RequestHandlerClass) |
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416 | self.socket = socket.socket(self.address_family, |
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417 | self.socket_type) |
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418 | if bind_and_activate: |
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419 | try: |
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420 | self.server_bind() |
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421 | self.server_activate() |
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422 | except: |
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423 | self.server_close() |
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424 | raise |
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425 | |
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426 | def server_bind(self): |
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427 | """Called by constructor to bind the socket. |
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428 | |
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429 | May be overridden. |
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430 | |
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431 | """ |
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432 | if self.allow_reuse_address: |
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433 | self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) |
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434 | self.socket.bind(self.server_address) |
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435 | self.server_address = self.socket.getsockname() |
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436 | |
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437 | def server_activate(self): |
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438 | """Called by constructor to activate the server. |
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439 | |
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440 | May be overridden. |
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441 | |
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442 | """ |
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443 | self.socket.listen(self.request_queue_size) |
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444 | |
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445 | def server_close(self): |
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446 | """Called to clean-up the server. |
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447 | |
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448 | May be overridden. |
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449 | |
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450 | """ |
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451 | self.socket.close() |
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452 | |
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453 | def fileno(self): |
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454 | """Return socket file number. |
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455 | |
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456 | Interface required by select(). |
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457 | |
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458 | """ |
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459 | return self.socket.fileno() |
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460 | |
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461 | def get_request(self): |
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462 | """Get the request and client address from the socket. |
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463 | |
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464 | May be overridden. |
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465 | |
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466 | """ |
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467 | return self.socket.accept() |
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468 | |
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469 | def shutdown_request(self, request): |
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470 | """Called to shutdown and close an individual request.""" |
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471 | try: |
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472 | #explicitly shutdown. socket.close() merely releases |
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473 | #the socket and waits for GC to perform the actual close. |
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474 | request.shutdown(socket.SHUT_WR) |
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475 | except socket.error: |
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476 | pass #some platforms may raise ENOTCONN here |
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477 | self.close_request(request) |
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478 | |
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479 | def close_request(self, request): |
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480 | """Called to clean up an individual request.""" |
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481 | request.close() |
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482 | |
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483 | |
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484 | class UDPServer(TCPServer): |
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485 | |
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486 | """UDP server class.""" |
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487 | |
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488 | allow_reuse_address = False |
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489 | |
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490 | socket_type = socket.SOCK_DGRAM |
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491 | |
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492 | max_packet_size = 8192 |
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493 | |
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494 | def get_request(self): |
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495 | data, client_addr = self.socket.recvfrom(self.max_packet_size) |
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496 | return (data, self.socket), client_addr |
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497 | |
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498 | def server_activate(self): |
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499 | # No need to call listen() for UDP. |
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500 | pass |
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501 | |
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502 | def shutdown_request(self, request): |
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503 | # No need to shutdown anything. |
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504 | self.close_request(request) |
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505 | |
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506 | def close_request(self, request): |
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507 | # No need to close anything. |
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508 | pass |
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509 | |
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510 | class ForkingMixIn: |
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511 | |
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512 | """Mix-in class to handle each request in a new process.""" |
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513 | |
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514 | timeout = 300 |
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515 | active_children = None |
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516 | max_children = 40 |
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517 | |
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518 | def collect_children(self): |
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519 | """Internal routine to wait for children that have exited.""" |
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520 | if self.active_children is None: |
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521 | return |
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522 | |
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523 | # If we're above the max number of children, wait and reap them until |
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524 | # we go back below threshold. Note that we use waitpid(-1) below to be |
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525 | # able to collect children in size(<defunct children>) syscalls instead |
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526 | # of size(<children>): the downside is that this might reap children |
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527 | # which we didn't spawn, which is why we only resort to this when we're |
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528 | # above max_children. |
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529 | while len(self.active_children) >= self.max_children: |
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530 | try: |
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531 | pid, _ = os.waitpid(-1, 0) |
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532 | self.active_children.discard(pid) |
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533 | except OSError as e: |
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534 | if e.errno == errno.ECHILD: |
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535 | # we don't have any children, we're done |
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536 | self.active_children.clear() |
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537 | elif e.errno != errno.EINTR: |
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538 | break |
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539 | |
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540 | # Now reap all defunct children. |
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541 | for pid in self.active_children.copy(): |
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542 | try: |
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543 | pid, _ = os.waitpid(pid, os.WNOHANG) |
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544 | # if the child hasn't exited yet, pid will be 0 and ignored by |
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545 | # discard() below |
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546 | self.active_children.discard(pid) |
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547 | except OSError as e: |
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548 | if e.errno == errno.ECHILD: |
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549 | # someone else reaped it |
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550 | self.active_children.discard(pid) |
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551 | |
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552 | def handle_timeout(self): |
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553 | """Wait for zombies after self.timeout seconds of inactivity. |
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554 | |
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555 | May be extended, do not override. |
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556 | """ |
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557 | self.collect_children() |
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558 | |
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559 | def process_request(self, request, client_address): |
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560 | """Fork a new subprocess to process the request.""" |
---|
561 | self.collect_children() |
---|
562 | pid = os.fork() |
---|
563 | if pid: |
---|
564 | # Parent process |
---|
565 | if self.active_children is None: |
---|
566 | self.active_children = set() |
---|
567 | self.active_children.add(pid) |
---|
568 | self.close_request(request) #close handle in parent process |
---|
569 | return |
---|
570 | else: |
---|
571 | # Child process. |
---|
572 | # This must never return, hence os._exit()! |
---|
573 | try: |
---|
574 | self.finish_request(request, client_address) |
---|
575 | self.shutdown_request(request) |
---|
576 | os._exit(0) |
---|
577 | except: |
---|
578 | try: |
---|
579 | self.handle_error(request, client_address) |
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580 | self.shutdown_request(request) |
---|
581 | finally: |
---|
582 | os._exit(1) |
---|
583 | |
---|
584 | |
---|
585 | class ThreadingMixIn: |
---|
586 | """Mix-in class to handle each request in a new thread.""" |
---|
587 | |
---|
588 | # Decides how threads will act upon termination of the |
---|
589 | # main process |
---|
590 | daemon_threads = False |
---|
591 | |
---|
592 | def process_request_thread(self, request, client_address): |
---|
593 | """Same as in BaseServer but as a thread. |
---|
594 | |
---|
595 | In addition, exception handling is done here. |
---|
596 | |
---|
597 | """ |
---|
598 | try: |
---|
599 | self.finish_request(request, client_address) |
---|
600 | self.shutdown_request(request) |
---|
601 | except: |
---|
602 | self.handle_error(request, client_address) |
---|
603 | self.shutdown_request(request) |
---|
604 | |
---|
605 | def process_request(self, request, client_address): |
---|
606 | """Start a new thread to process the request.""" |
---|
607 | t = threading.Thread(target = self.process_request_thread, |
---|
608 | args = (request, client_address)) |
---|
609 | t.daemon = self.daemon_threads |
---|
610 | t.start() |
---|
611 | |
---|
612 | |
---|
613 | class ForkingUDPServer(ForkingMixIn, UDPServer): pass |
---|
614 | class ForkingTCPServer(ForkingMixIn, TCPServer): pass |
---|
615 | |
---|
616 | class ThreadingUDPServer(ThreadingMixIn, UDPServer): pass |
---|
617 | class ThreadingTCPServer(ThreadingMixIn, TCPServer): pass |
---|
618 | |
---|
619 | if hasattr(socket, 'AF_UNIX'): |
---|
620 | |
---|
621 | class UnixStreamServer(TCPServer): |
---|
622 | address_family = socket.AF_UNIX |
---|
623 | |
---|
624 | class UnixDatagramServer(UDPServer): |
---|
625 | address_family = socket.AF_UNIX |
---|
626 | |
---|
627 | class ThreadingUnixStreamServer(ThreadingMixIn, UnixStreamServer): pass |
---|
628 | |
---|
629 | class ThreadingUnixDatagramServer(ThreadingMixIn, UnixDatagramServer): pass |
---|
630 | |
---|
631 | class BaseRequestHandler: |
---|
632 | |
---|
633 | """Base class for request handler classes. |
---|
634 | |
---|
635 | This class is instantiated for each request to be handled. The |
---|
636 | constructor sets the instance variables request, client_address |
---|
637 | and server, and then calls the handle() method. To implement a |
---|
638 | specific service, all you need to do is to derive a class which |
---|
639 | defines a handle() method. |
---|
640 | |
---|
641 | The handle() method can find the request as self.request, the |
---|
642 | client address as self.client_address, and the server (in case it |
---|
643 | needs access to per-server information) as self.server. Since a |
---|
644 | separate instance is created for each request, the handle() method |
---|
645 | can define arbitrary other instance variariables. |
---|
646 | |
---|
647 | """ |
---|
648 | |
---|
649 | def __init__(self, request, client_address, server): |
---|
650 | self.request = request |
---|
651 | self.client_address = client_address |
---|
652 | self.server = server |
---|
653 | self.setup() |
---|
654 | try: |
---|
655 | self.handle() |
---|
656 | finally: |
---|
657 | self.finish() |
---|
658 | |
---|
659 | def setup(self): |
---|
660 | pass |
---|
661 | |
---|
662 | def handle(self): |
---|
663 | pass |
---|
664 | |
---|
665 | def finish(self): |
---|
666 | pass |
---|
667 | |
---|
668 | |
---|
669 | # The following two classes make it possible to use the same service |
---|
670 | # class for stream or datagram servers. |
---|
671 | # Each class sets up these instance variables: |
---|
672 | # - rfile: a file object from which receives the request is read |
---|
673 | # - wfile: a file object to which the reply is written |
---|
674 | # When the handle() method returns, wfile is flushed properly |
---|
675 | |
---|
676 | |
---|
677 | class StreamRequestHandler(BaseRequestHandler): |
---|
678 | |
---|
679 | """Define self.rfile and self.wfile for stream sockets.""" |
---|
680 | |
---|
681 | # Default buffer sizes for rfile, wfile. |
---|
682 | # We default rfile to buffered because otherwise it could be |
---|
683 | # really slow for large data (a getc() call per byte); we make |
---|
684 | # wfile unbuffered because (a) often after a write() we want to |
---|
685 | # read and we need to flush the line; (b) big writes to unbuffered |
---|
686 | # files are typically optimized by stdio even when big reads |
---|
687 | # aren't. |
---|
688 | rbufsize = -1 |
---|
689 | wbufsize = 0 |
---|
690 | |
---|
691 | # A timeout to apply to the request socket, if not None. |
---|
692 | timeout = None |
---|
693 | |
---|
694 | # Disable nagle algorithm for this socket, if True. |
---|
695 | # Use only when wbufsize != 0, to avoid small packets. |
---|
696 | disable_nagle_algorithm = False |
---|
697 | |
---|
698 | def setup(self): |
---|
699 | self.connection = self.request |
---|
700 | if self.timeout is not None: |
---|
701 | self.connection.settimeout(self.timeout) |
---|
702 | if self.disable_nagle_algorithm: |
---|
703 | self.connection.setsockopt(socket.IPPROTO_TCP, |
---|
704 | socket.TCP_NODELAY, True) |
---|
705 | self.rfile = self.connection.makefile('rb', self.rbufsize) |
---|
706 | self.wfile = self.connection.makefile('wb', self.wbufsize) |
---|
707 | |
---|
708 | def finish(self): |
---|
709 | if not self.wfile.closed: |
---|
710 | try: |
---|
711 | self.wfile.flush() |
---|
712 | except socket.error: |
---|
713 | # An final socket error may have occurred here, such as |
---|
714 | # the local error ECONNABORTED. |
---|
715 | pass |
---|
716 | self.wfile.close() |
---|
717 | self.rfile.close() |
---|
718 | |
---|
719 | |
---|
720 | class DatagramRequestHandler(BaseRequestHandler): |
---|
721 | |
---|
722 | # XXX Regrettably, I cannot get this working on Linux; |
---|
723 | # s.recvfrom() doesn't return a meaningful client address. |
---|
724 | |
---|
725 | """Define self.rfile and self.wfile for datagram sockets.""" |
---|
726 | |
---|
727 | def setup(self): |
---|
728 | try: |
---|
729 | from cStringIO import StringIO |
---|
730 | except ImportError: |
---|
731 | from StringIO import StringIO |
---|
732 | self.packet, self.socket = self.request |
---|
733 | self.rfile = StringIO(self.packet) |
---|
734 | self.wfile = StringIO() |
---|
735 | |
---|
736 | def finish(self): |
---|
737 | self.socket.sendto(self.wfile.getvalue(), self.client_address) |
---|