Doc/lib/libcgihttp.tex

   1 \section{\module{CGIHTTPServer} ---
   2          CGI-capable HTTP request handler}
   3
   4
   5 \declaremodule{standard}{CGIHTTPServer}
   6 \sectionauthor{Moshe Zadka}{moshez@zadka.site.co.il}
   7 \modulesynopsis{This module provides a request handler for HTTP servers
   8                 which can run CGI scripts.}
   9
  10
  11 The \module{CGIHTTPServer} module defines a request-handler class,
  12 interface compatible with
  13 \class{BaseHTTPServer.BaseHTTPRequestHandler} and inherits behavior
  14 from \class{SimpleHTTPServer.SimpleHTTPRequestHandler} but can also
  15 run CGI scripts.
  16
  17 \note{This module can run CGI scripts on \UNIX{} and Windows systems;
  18 on Mac OS it will only be able to run Python scripts within the same
  19 process as itself.}
  20
  21 \note{CGI scripts run by the \class{CGIHTTPRequestHandler} class cannot execute
  22 redirects (HTTP code 302), because code 200 (script output follows)
  23 is sent prior to execution of the CGI script.  This pre-empts the status
  24 code.}
  25
  26 The \module{CGIHTTPServer} module defines the following class:
  27
  28 \begin{classdesc}{CGIHTTPRequestHandler}{request, client_address, server}
  29 This class is used to serve either files or output of CGI scripts from
  30 the current directory and below. Note that mapping HTTP hierarchic
  31 structure to local directory structure is exactly as in
  32 \class{SimpleHTTPServer.SimpleHTTPRequestHandler}.
  33
  34 The class will however, run the CGI script, instead of serving it as a
  35 file, if it guesses it to be a CGI script. Only directory-based CGI
  36 are used --- the other common server configuration is to treat special
  37 extensions as denoting CGI scripts.
  38
  39 The \function{do_GET()} and \function{do_HEAD()} functions are
  40 modified to run CGI scripts and serve the output, instead of serving
  41 files, if the request leads to somewhere below the
  42 \code{cgi_directories} path.
  43 \end{classdesc}
  44
  45 The \class{CGIHTTPRequestHandler} defines the following data member:
  46
  47 \begin{memberdesc}{cgi_directories}
  48 This defaults to \code{['/cgi-bin', '/htbin']} and describes
  49 directories to treat as containing CGI scripts.
  50 \end{memberdesc}
  51
  52 The \class{CGIHTTPRequestHandler} defines the following methods:
  53
  54 \begin{methoddesc}{do_POST}{}
  55 This method serves the \code{'POST'} request type, only allowed for
  56 CGI scripts.  Error 501, "Can only POST to CGI scripts", is output
  57 when trying to POST to a non-CGI url.
  58 \end{methoddesc}
  59
  60 Note that CGI scripts will be run with UID of user nobody, for security
  61 reasons. Problems with the CGI script will be translated to error 403.
  62
  63 For example usage, see the implementation of the \function{test()}
  64 function.
  65
  66
  67 \begin{seealso}
  68   \seemodule{BaseHTTPServer}{Base class implementation for Web server
  69                              and request handler.}
  70 \end{seealso}