1 """ |
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2 WSGI HTTP utility code |
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3 """ |
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4 |
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5 # for utility functions |
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6 import cgi |
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7 |
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8 # for header handling |
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9 import wsgiref.headers |
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10 |
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11 # for path handling |
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12 import os.path |
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13 |
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14 class Request (object) : |
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15 """ |
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16 HTTP Request with associated metadata |
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17 """ |
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18 |
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19 def __init__ (self, env) : |
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20 """ |
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21 Parse env data |
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22 """ |
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23 |
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24 # store env |
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25 self.env = env |
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26 |
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27 # get the querystring |
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28 self.arg_str = env.get('QUERY_STRING', '') |
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29 |
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30 # parse query args |
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31 self.arg_dict = cgi.parse_qs(self.arg_str, True) |
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32 |
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33 @property |
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34 def site_host (self) : |
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35 """ |
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36 Returns the site's hostname (DNS name) |
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37 """ |
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38 |
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39 return self.env['HTTP_HOST'] |
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40 |
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41 @property |
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42 def site_root (self) : |
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43 """ |
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44 Returns the URL path to the requested script's directory with no trailing slash, i.e. |
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45 |
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46 / -> |
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47 /foo.cgi -> |
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48 /foo/bar.cgi -> /foo |
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49 """ |
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50 |
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51 return os.path.dirname(self.env['SCRIPT_NAME']).rstrip('/') |
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52 |
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53 @property |
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54 def page_prefix (self) : |
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55 """ |
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56 Returns the URL path root for page URLs, based on REQUEST_URI with PATH_INFO removed |
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57 |
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58 / -> |
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59 /foo.cgi -> /foo.cgi |
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60 /foo.cgi/index -> /foo.cgi |
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61 /foo.cgi/quux/bar -> /foo.cgi |
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62 /quux/foo.cgi/bar -> /quux/foo.cgi |
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63 /bar -> |
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64 """ |
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65 |
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66 # XXX: request uri path without the query string |
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67 request_path = self.env.get('REQUEST_URI', '').split('?', 1)[0].rstrip('/') |
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68 |
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69 # path info |
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70 page_name = self.get_page_name() |
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71 |
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72 # special-case for empty page_name |
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73 if not page_name : |
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74 return request_path |
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75 |
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76 # sanity-check |
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77 assert request_path.endswith(page_name) |
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78 |
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79 # trim |
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80 return request_path[:-len(page_name)].rstrip('/') |
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81 |
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82 def get_page_name (self) : |
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83 """ |
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84 Returns the requested page path with no leading slash, i.e. |
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85 |
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86 /foo.cgi -> |
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87 /foo.cgi/ -> |
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88 /foo.cgi/bar -> bar |
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89 /foo.cgi/quux/ -> quux/ |
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90 """ |
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91 |
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92 # the raw PATH_INFO |
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93 path_info = self.env.get('PATH_INFO') |
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94 |
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95 # avoid nasty '.' paths |
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96 if path_info : |
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97 return os.path.normpath(path_info).lstrip('/') |
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98 |
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99 else : |
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100 return '' |
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101 |
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102 def get_args (self) : |
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103 """ |
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104 Iterate over all available (key, value) pairs from the query string |
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105 """ |
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106 |
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107 return cgi.parse_qsl(self.arg_str) |
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108 |
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109 class Response (object) : |
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110 """ |
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111 HTTP Response with headers and data |
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112 """ |
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113 |
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114 def __init__ (self, data, content_type='text/html', status='200 OK', charset='UTF-8') : |
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115 """ |
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116 Create the response. The Content-type header is built from the given values. The given \a data must be |
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117 either a str (which is sent plain), an unicode object (which is encoded with the relevant charset), or |
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118 None, whereupon an empty response body is sent. The content_type argument can also be forced to None to |
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119 not send a Content-type header (e.g. for redirects) |
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120 """ |
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121 |
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122 # store info |
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123 self.status = status |
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124 self.data = data |
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125 self.charset = charset |
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126 |
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127 # headers |
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128 self.headers = wsgiref.headers.Headers([]) |
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129 |
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130 # add Content-type header? |
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131 if content_type : |
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132 self.add_header('Content-type', content_type, charset=charset) |
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133 |
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134 def add_header (self, name, value, **params) : |
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135 """ |
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136 Add response header with the given name/value, plus option params |
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137 |
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138 XXX: uses the wsgiref.headers code, not sure how that behaves re multiple headers with the same name, etc |
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139 """ |
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140 |
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141 self.headers.add_header(name, value, **params) |
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142 |
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143 def get_status (self) : |
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144 """ |
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145 Returns response status string (XXX Foo) |
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146 """ |
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147 |
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148 return self.status |
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149 |
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150 def get_headers (self) : |
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151 """ |
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152 Returns the list of header (name, value) pairs |
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153 """ |
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154 |
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155 return self.headers.items() |
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156 |
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157 def get_data (self) : |
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158 """ |
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159 Returns the response data - as an encoded string |
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160 """ |
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161 |
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162 if self.data : |
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163 return self.data.encode(self.charset) |
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164 |
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165 else : |
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166 return '' |
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167 |
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168 class ErrorResponse (Response) : |
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169 """ |
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170 A response with an error code / message |
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171 """ |
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172 |
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173 def __init__ (self, status, message, details=None) : |
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174 """ |
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175 Build a plain error message response with the given status/message |
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176 |
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177 @param status HTTP status code |
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178 @param message short message to describe errors |
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179 @param details optional details, plaintext |
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180 """ |
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181 |
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182 data = """\ |
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183 <html><head><title>%(title)s</title></head><body> |
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184 <h1>%(title)s</h1> |
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185 <p>%(message)s</p> |
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186 %(details)s |
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187 </body></html> |
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188 """ % dict( |
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189 title = status, |
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190 message = message, |
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191 details = '<pre>%s</pre>' % details if details else '' |
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192 ) |
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193 |
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194 super(ErrorResponse, self).__init__(data, status=status) |
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195 |
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196 class ResponseError (Exception) : |
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197 """ |
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198 An exception that results in a specfic 4xx ErrorResponse message to the client |
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199 """ |
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200 |
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201 def __init__ (self, message, status='400 Bad Request', details=None) : |
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202 self.status = status |
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203 self.message = message |
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204 self.details = details |
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205 |
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206 super(ResponseError, self).__init__(message) |
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207 |
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208 def get_response (self) : |
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209 return ErrorResponse(self.status, self.message, self.details) |
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210 |
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211 class Redirect (Response) : |
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212 """ |
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213 Redirect response |
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214 """ |
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215 |
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216 def __init__ (self, url) : |
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217 """ |
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218 Redirect to given *absolute* URL |
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219 """ |
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220 |
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221 # no content-type or data |
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222 super(Redirect, self).__init__(None, content_type=None, status='302 Found') |
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223 |
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224 # add Location: header |
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225 self.add_header("Location", url) |
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226 |
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227 |
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