~azzar1/unity/add-show-desktop-key

414 by mattgiuca
Added common/cgirequest.py. This takes the CGI environment and wraps it in a
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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2008 The University of Melbourne
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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# Module: cgirequest
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# Author: Matt Giuca
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# Date:   5/2/2007
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# Presents a CGIRequest class which creates an object compatible with IVLE
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# Request objects (the same interface exposed by www.dispatch.request) from a
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# CGI script.
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# This allows CGI scripts to create request objects and then pass them to
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# normal IVLE handlers.
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# NOTE: This object does not support write_html_head_foot (simply because we
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# do not need it in its intended application: fileservice).
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import sys
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import os
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import cgi
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import conf
423 by mattgiuca
common.cgirequest: Added some missing includes.
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import common
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import common.util
414 by mattgiuca
Added common/cgirequest.py. This takes the CGI environment and wraps it in a
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# Utility functions
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def _http_headers_in_from_cgi():
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    """Returns a dictionary of HTTP headers and their values, reading from the
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    CGI environment."""
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    d = {}
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    for k in os.environ.keys():
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        if k.startswith("HTTP_"):
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            # Change the case - underscores become - and each word is
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            # capitalised
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            varname = '-'.join(map(lambda x: x[0:1] + x[1:].lower(),
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                                k[5:].split('_')))
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            d[varname] = os.environ[k]
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    return d
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class CGIRequest:
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    """An IVLE request object, built from a CGI script. This is presented to
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    the IVLE apps as a way of interacting with the CGI server.
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    See dispatch.request for a full interface specification.
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    """
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    # COPIED from dispatch/request.py
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    # Special code for an OK response.
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    # Do not use HTTP_OK; for some reason Apache produces an "OK" error
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    # message if you do that.
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    OK  = 0
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    # HTTP status codes
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    HTTP_CONTINUE                     = 100
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    HTTP_SWITCHING_PROTOCOLS          = 101
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    HTTP_PROCESSING                   = 102
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    HTTP_OK                           = 200
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    HTTP_CREATED                      = 201
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    HTTP_ACCEPTED                     = 202
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    HTTP_NON_AUTHORITATIVE            = 203
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    HTTP_NO_CONTENT                   = 204
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    HTTP_RESET_CONTENT                = 205
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    HTTP_PARTIAL_CONTENT              = 206
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    HTTP_MULTI_STATUS                 = 207
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    HTTP_MULTIPLE_CHOICES             = 300
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    HTTP_MOVED_PERMANENTLY            = 301
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    HTTP_MOVED_TEMPORARILY            = 302
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    HTTP_SEE_OTHER                    = 303
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    HTTP_NOT_MODIFIED                 = 304
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    HTTP_USE_PROXY                    = 305
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    HTTP_TEMPORARY_REDIRECT           = 307
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    HTTP_BAD_REQUEST                  = 400
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    HTTP_UNAUTHORIZED                 = 401
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    HTTP_PAYMENT_REQUIRED             = 402
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    HTTP_FORBIDDEN                    = 403
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    HTTP_NOT_FOUND                    = 404
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    HTTP_METHOD_NOT_ALLOWED           = 405
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    HTTP_NOT_ACCEPTABLE               = 406
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    HTTP_PROXY_AUTHENTICATION_REQUIRED= 407
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    HTTP_REQUEST_TIME_OUT             = 408
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    HTTP_CONFLICT                     = 409
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    HTTP_GONE                         = 410
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    HTTP_LENGTH_REQUIRED              = 411
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    HTTP_PRECONDITION_FAILED          = 412
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    HTTP_REQUEST_ENTITY_TOO_LARGE     = 413
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    HTTP_REQUEST_URI_TOO_LARGE        = 414
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    HTTP_UNSUPPORTED_MEDIA_TYPE       = 415
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    HTTP_RANGE_NOT_SATISFIABLE        = 416
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    HTTP_EXPECTATION_FAILED           = 417
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    HTTP_UNPROCESSABLE_ENTITY         = 422
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    HTTP_LOCKED                       = 423
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    HTTP_FAILED_DEPENDENCY            = 424
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    HTTP_INTERNAL_SERVER_ERROR        = 500
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    HTTP_NOT_IMPLEMENTED              = 501
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    HTTP_BAD_GATEWAY                  = 502
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    HTTP_SERVICE_UNAVAILABLE          = 503
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    HTTP_GATEWAY_TIME_OUT             = 504
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    HTTP_VERSION_NOT_SUPPORTED        = 505
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    HTTP_VARIANT_ALSO_VARIES          = 506
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    HTTP_INSUFFICIENT_STORAGE         = 507
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    HTTP_NOT_EXTENDED                 = 510
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    def __init__(self):
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        """Builds an CGI Request object from the current CGI environment.
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        This results in an object with all of the necessary methods and
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        additional fields.
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        """
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        self.headers_written = False
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419 by mattgiuca
cgirequest: Throws an exception if important CGI variables are not found.
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        if ('SERVER_NAME' not in os.environ or
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            'REQUEST_METHOD' not in os.environ or
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            'REQUEST_URI' not in os.environ):
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            raise Exception("No CGI environment found")
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414 by mattgiuca
Added common/cgirequest.py. This takes the CGI environment and wraps it in a
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        # Determine if the browser used the public host name to make the
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        # request (in which case we are in "public mode")
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        if os.environ['SERVER_NAME'] == conf.public_host:
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            self.publicmode = True
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        else:
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            self.publicmode = False
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        # Inherit values for the input members
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        self.method = os.environ['REQUEST_METHOD']
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        self.uri = os.environ['REQUEST_URI']
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        # Split the given path into the app (top-level dir) and sub-path
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        # (after first stripping away the root directory)
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        path = common.util.unmake_path(self.uri)
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        if self.publicmode:
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            self.app = None
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            self.path = path
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        else:
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            (self.app, self.path) = (common.util.split_path(path))
505 by mattgiuca
dispatch.html, consoleservice, userservice, interpret:
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        self.user = None
414 by mattgiuca
Added common/cgirequest.py. This takes the CGI environment and wraps it in a
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        self.hostname = os.environ['SERVER_NAME']
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        self.headers_in = _http_headers_in_from_cgi()
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        self.headers_out = {}
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        # Default values for the output members
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        self.status = CGIRequest.HTTP_OK
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        self.content_type = None        # Use Apache's default
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        self.location = None
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        self.title = None     # Will be set by dispatch before passing to app
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        self.styles = []
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        self.scripts = []
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        self.write_html_head_foot = False
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        self.got_common_vars = False
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    def __writeheaders(self):
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        """Writes out the HTTP and HTML headers before any real data is
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        written."""
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        self.headers_written = True
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        if 'Content-Type' in self.headers_out:
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            self.content_type = self.headers_out['Content-Type']
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        if 'Location' in self.headers_out:
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            self.location = self.headers_out['Location']
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        # CGI allows for four response types: Document, Local Redirect, Client
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        # Redirect, and Client Redirect w/ Document
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        # XXX We do not allow Local Redirect
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        if self.location != None:
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            # This is a Client Redirect
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            print "Location: %s" % self.location
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            if self.content_type == None:
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                # Just redirect
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                return
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            # Else: This is a Client Redirect with Document
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            print "Status: %d" % self.status
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            print "Content-Type: %s" % self.content_type
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        else:
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            # This is a Document response
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            print "Content-Type: %s" % self.content_type
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            print "Status: %d" % self.status
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        # Print the other headers
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        for k,v in self.headers_out.items():
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            if k != 'Content-Type' and k != 'Location':
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                print "%s: %s" % (k, v)
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        # XXX write_html_head_foot not supported
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        #if self.write_html_head_foot:
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        #    # Write the HTML header, pass "self" (request object)
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        #    self.func_write_html_head(self)
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        # Print a blank line to signal the start of output
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        print
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    def ensure_headers_written(self):
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        """Writes out the HTTP and HTML headers if they haven't already been
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        written."""
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        if not self.headers_written:
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            self.__writeheaders()
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    def write(self, string, flush=1):
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        """Writes string directly to the client, then flushes the buffer,
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        unless flush is 0."""
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        if not self.headers_written:
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            self.__writeheaders()
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        if isinstance(string, unicode):
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            # Encode unicode strings as UTF-8
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            # (Otherwise cannot handle being written to a bytestream)
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            sys.stdout.write(string.encode('utf8'))
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        else:
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            # 8-bit clean strings just get written directly.
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            # This includes binary strings.
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            sys.stdout.write(string)
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    def flush(self):
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        """Flushes the output buffer."""
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        sys.stdout.flush()
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    def sendfile(self, filename):
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        """Sends the named file directly to the client."""
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        if not self.headers_written:
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            self.__writeheaders()
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        f = open(filename)
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        buf = f.read(1024)
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        while len(buf) > 0:
436 by drtomc
fileservice: Make things less broken than they were. No claims of perfection yet! Unpacking form data with cgi.py is AWFUL.
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            sys.stdout.write(buf)
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            sys.stdout.flush()
414 by mattgiuca
Added common/cgirequest.py. This takes the CGI environment and wraps it in a
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            buf = f.read(1024)
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        f.close()
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    def read(self, len=None):
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        """Reads at most len bytes directly from the client. (See mod_python
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        Request.read)."""
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        if len is None:
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            return sys.stdin.read()
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        else:
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            return sys.stdin.read(len)
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    def throw_error(self, httpcode):
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        """Writes out an HTTP error of the specified code. Exits the process,
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        so any code following this call will not be executed.
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        (This is justified because of the nature of CGI, it is a single-script
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        environment, there is no containing process which needs to catch an
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        exception).
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        httpcode: An HTTP response status code. Pass a constant from the
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        Request class.
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        """
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        self.status = httpcode
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        self.content_type = "text/html"
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        # Emulate an Apache error
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        self.write("""<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
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<html><head>
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<title>%d Error</title>
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</head><body>
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<h1>Error</h1>
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<p>A %d error was triggered by a CGI app.</p>
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</body></html>
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""" % (httpcode, httpcode))
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        # Exit the process completely
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        self.flush()
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        sys.exit(httpcode)
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    def throw_redirect(self, location):
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        """Writes out an HTTP redirect to the specified URL. Exits the
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        process, so any code following this call will not be executed.
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        httpcode: An HTTP response status code. Pass a constant from the
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        Request class.
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        """
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        self.status = CGIRequest.HTTP_MOVED_TEMPORARILY
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        self.location = location
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        self.ensure_headers_written()
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        self.flush()
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        sys.exit(self.status)
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    def get_session(self):
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        """Returns a mod_python Session object for this request.
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        Note that this is dependent on mod_python and may need to change
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        interface if porting away from mod_python."""
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        # Cache the session object
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        if not hasattr(self, 'session'):
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            #self.session = Session.FileSession(self.apache_req)
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            self.session = None
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            # FIXME: How to get session?
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        return self.session
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    def get_fieldstorage(self):
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        """Returns a mod_python FieldStorage object for this request.
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        Note that this is dependent on mod_python and may need to change
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        interface if porting away from mod_python."""
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        # Cache the fieldstorage object
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        if not hasattr(self, 'fields'):
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            self.fields = cgi.FieldStorage()
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        return self.fields
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    def get_cgi_environ(self):
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        """Returns the CGI environment emulation for this request. (Calls
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        add_common_vars). The environment is returned as a mapping
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        compatible with os.environ."""
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        return os.environ