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NAME

Embperl base class for defining custom recipes

SYNOPSIS

PerlSetEnv EMBPERL_RECIPE "XSLT Embperl"

DESCRIPTION

HTML::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 new method which returns a hash that contains the description what to do.

new ($class, $r, $recipe, $param)

$class

The class name

$r

The Embperl request record object (HTML::Embperl::Req), maybe a derived object when running under EmbperlObject.

$recipe

The name of the recipe

$param

The parameters the user passed to Execute.

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

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

Cache parameter

expires_in
expires_func
expires_filename
cache

Format

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

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

    my $self =
        {
        'provider' => 
            {
            'type' => 'xalan',
            'source' => 
                {
                'cache'    => 0,
                provider =>
                    {
                    'type'      =>  'xalan-parse-xml',
                    'source' =>
                        {
                       'cache' => 0,
                        provider => 
                            {
                            'type'      =>  'file',
                            'filename'  => $param -> {inputfile},
                            }
                        },
                    },
                },
            'stylesheet' => 
                {
                'cache'    => 1,
                provider =>
                    {
                    'type'      =>  'xalan-compile-xsl',
                    'stylesheet' =>
                        {
                        'cache'    => 0,
                        provider =>
                            {
                            'type'      =>  'file',
                            'filename'  => $param -> {xsltstylesheet},
                            }
                        },
                    },
                }
            }
        } ;

    return $self ;
    }

This corresponds to the following diagramm:

    +-------------------+   +--------------------+           
    + 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.