Embperl - building dynamic websites with Perl

• get_recipe ($class, $r, $recipe)
• Providers
• Cache parameter
• Format

Embperl::Recipe provides basic features that are necessary for createing your own recipes. To do so you have to create a class that provides a get_recipe method which returns a array reference that contains the description what to do.

	$class
	The class name
	$r
	The Embperl request record object (Embperl::Req), maybe a derived object when running under EmbperlObject.
	$recipe
	The name of the recipe

The function must return an array that describes the desired action. The array contains a tree structure of providers.

	file
	read file data Parameter:   filename   Gives the file to read
	memory
	get data from a scalar Parameter:   source   Gives the source as a scalar reference   name   Gives the name under which this item should be cache
	epparse
	parse file into a Embperl tree structure Parameter:   source   Gives the source   syntax   Syntax to use
	epcompile
	compile Embperl tree structure Parameter:   source   Gives the source
	eprun
	execute Embperl tree structure Parameter:   source   Gives the source   cache_key   See description of cacheing   cache_key_options   See description of cacheing   cache_key_func   See description of cacheing
	eptostring
	convert Embperl tree structure to string Parameter:   source   Gives the source
	libxslt-parse-xml
	parse xml source for libxslt Parameter:   source   Gives the xml source
	libxslt-compile-xsl
	parse and compile stylesheet for libxslt Parameter:   stylesheet   Gives the stylesheet source
	libxslt
	do a xsl transformation via libxslt Parameter:   source   Gives the parsed xml source   stylesheet   Gives the compiled stylesheet source   param   Gives the parameters as hash ref
	xalan-parse-xml
	parse xml source for xalan Parameter:   source   Gives the xml source
	xalan-compile-xsl
	parse and compile stylesheet for xalan Parameter:   stylesheet   Gives the stylesheet source
	xalan
	do a xsl transformation via xalan Parameter:   source   Gives the parsed xml source   stylesheet   Gives the compiled stylesheet source   param   Gives the parameters as hash ref

	expires_in
	expires_func
	expires_filename
	cache

Heres an example that show how the recipe must be build:

  sub get_recipe

    {
    my ($class, $r, $recipe) = @_ ;

    my $param  = $r -> component -> param  ;
    my @recipe ;

    push @recipe, {'type'   =>  'file'      } ;
    push @recipe, {'type'   =>  'epparse'   } ;
    push @recipe, {'type'   =>  'epcompile', cache => 1 } ;
    push @recipe, {'type'   =>  'eprun'     }  ;

    my $config = $r -> component -> config  ;
    my $xsltproc = $config -> xsltproc ;

    my @stylesheet =
        (
        { type => 'file',  filename  => $config -> xsltstylesheet, },
        { type =>  $xsltproc . '-compile-xsl', cache => 1 },
        ) ;

    push @recipe, {'type'   =>  'eptostring' } ;
    push @recipe, {'type'   =>  $xsltproc . '-parse-xml', } ;
    push @recipe, {'type'   =>  $xsltproc,   stylesheet => \@stylesheet } ;

    return \@recipe ;
    }

This corresponds to the following diagramm (when xsltproc = xalan):

    +-------------------+   +--------------------+           
    + file {inputfile}  +   +file{xsltstylesheet}+           
    +-------------------+   +--------------------+           
          |                         |                         
          v                         v                         
    +-------------------+   +-------------------+           
    + xalan-parse-xml   +   + xalan-compile-xsl +           
    +-------------------+   +-------------------+           
          |                         | 
          |                         |
          |         +-----------+   |
          +-------> + xalan     + <-+
                    +-----------+

Take a look at the recipes that comes with Embperl to get more ideas what can be done.