CGI::SSI - Use SSI from CGI scripts

 # autotie STDOUT or any other open filehandle

   use CGI::SSI (autotie => 'STDOUT');

   print $shtml; # browser sees resulting HTML

 # or tie it yourself to any open filehandle

   use CGI::SSI;

   open(FILE,'+>'.$html_file) or die $!;
   $ssi = tie(*FILE, 'CGI::SSI', filehandle => 'FILE');
   print FILE $shtml; # HTML arrives in the file

 # or use the object-oriented interface

   use CGI::SSI;

   $ssi = CGI::SSI->new();

   $ssi->if('"$varname" =~ /^foo/');
      $html .= $ssi->process($shtml);
   $ssi->else();
      $html .= $ssi->include(file => $filename);
   $ssi->endif();

   print $ssi->exec(cgi => $url);
   print $ssi->flastmod(file => $filename);

 #
 # or roll your own favorite flavor of SSI
 #

   package CGI::SSI::MySSI;
   use CGI::SSI;
   @CGI::SSI::MySSI::ISA = qw(CGI::SSI);

   sub include {
      my($self,$type,$file_or_url) = @_; 
      # my idea of include goes something like this...
      return $html;
   }
   1;
   __END__

 #
 # or use .htaccess to include all files in a dir
 #

   # in .htaccess
   Action cgi-ssi /cgi-bin/ssi/process.cgi
   <FilesMatch "\.shtml">
      SetHandler cgi-ssi
   </FilesMatch>

   # in /cgi-bin/ssi/process.cgi
   #!/usr/local/bin/perl 
   use CGI::SSI;
   CGI::SSI->handler();
   __END__

CGI::SSI is meant to be used as an easy way to filter shtml through CGI scripts in a loose imitation of Apache's mod_include. If you're using Apache, you may want to use either mod_include or the Apache::SSI module instead of CGI::SSI. Limitations in a CGI script's knowledge of how the server behaves make some SSI directives impossible to imitate from a CGI script.

Most of the time, you'll simply want to filter shtml through STDOUT or some other open filehandle. CWautotie is available for STDOUT, but in general, you'll want to tie other filehandles yourself:

    $ssi = tie(*FH, 'CGI::SSI', filehandle => 'FH');
    print FH $shtml;

Note that you'll need to pass the name of the filehandle to CWtie() as a named parameter. Other named parameters are possible, as detailed below. These parameters are the same as those passed to the CWnew() method. However, CWnew() will not tie a filehandle for you.

CGI::SSI has it's own flavor of SSI. Test expressions are Perlish. You may create and use multiple CGI::SSI objects; they will not step on each others' variables.

Object-Oriented methods use the same general format so as to imitate SSI directives:

    <!--#include virtual="/foo/bar.footer" -->

  would be

    $ssi->include(virtual => '/foo/bar.footer');

likewise,

    <!--#exec cgi="/cgi-bin/foo.cgi" -->

  would be

    $ssi->exec(cgi => '/cgi-bin/foo.cgi');

Usually, if there's no chance for ambiguity, the first argument may be left out:

    <!--#echo var="var_name" -->

  could be either

    $ssi->echo(var => 'var_name');

  or

    $ssi->echo('var_name');

Likewise,

    $ssi->set(var => $varname, value => $value)

  is the same as

    $ssi->set($varname => $value)

$ssi->new([%args])

Creates a new CGI::SSI object. The following are valid (optional) arguments:

 DOCUMENT_URI    => $doc_uri,
 DOCUMENT_NAME   => $doc_name,
 DOCUMENT_ROOT   => $doc_root,
 errmsg          => $oops,
 sizefmt         => ('bytes' || 'abbrev'),
 timefmt         => $time_fmt,
 MAX_RECURSIONS  => $default_100, # when to stop infinite loops w/ error msg
 COOKIE_JAR      => HTTP::Cookies->new,

$type is either 'sizefmt', 'timefmt', or 'errmsg'. CW$arg is similar to those of the SSI CWspec, referenced below. Sets variables internal to the CGI::SSI object. (Not to be confused with the normal variables your script uses!) These variables may be used in test expressions, and retreived using CW$ssi->echo($varname).

$ssi->echo($varname)

Returns the value of the variable named CW$varname. Such variables may be set manually using the CWset() method. There are also several built-in variables:

 DOCUMENT_URI  - the URI of this document
 DOCUMENT_NAME - the name of the current document
 DATE_GMT      - the same as 'gmtime'
 DATE_LOCAL    - the same as 'localtime'
 FLASTMOD      - the last time this script was modified

$type is either 'cmd' or 'cgi'. CW$arg is similar to the SSI CWspec (see below). Similar to CWexec, but CWvirtual and CWfile are the two valid types. Similar to CWinclude. Same as CWflastmod.

$ssi->printenv

Returns the environment similar to Apache's mod_include.

$ssi->cookie_jar([$jar])

Returns the currently-used HTTP::Cookies object. You may optionally pass in a new HTTP::Cookies object. The jar is used for web requests in exec cgi and include virtual directives.

The following methods may be used to test expressions. During a CWblock where the test CW$expr is false, nothing will be returned (or printed, if tied).

$ssi->if($expr)

The expr can be anything Perl, but care should be taken. This causes problems:

 $ssi->set(varname => "foo");
 <!--#if expr="'\$varname' =~ /^foo$/" -->ok<!--#endif -->

The CW$varname is expanded as you would expect. (We escape it so as to use the CW$varname within the CGI::SSI object, instead of that within our progam.) But the CW$/ inside the regex is also expanded. This is fixed by escaping the CW$:

 <!--#if expr="'\$varname' =~ /^value\$/" -->ok<!--#endif -->

The expressions used in if and elif tags/calls are tricky due to the number of escapes required. In some cases, you'll need to write CW\\\\ to mean CW\.

$ssi->elif($expr)

$ssi->else

$ssi->endif

CWApache::SSI and the SSI CWspec at http://www.apache.org/docs/mod/mod_include.html

(c) 2000-2005 James Tolley <james@bitperfect.com> All Rights Reserved.

This is free software. You may copy and/or modify it under the same terms as perl itself.

Many Thanks to Corey Wilson for a bug report and fix.