NAME

Jemplate - Javascript Templating with Template Toolkit

SYNOPSIS

var data = Ajax.get('url/data.json');
var elem = document.getElementById('some-div');
elem.innerHTML = Jemplate.process('my-template.html', data);

or:

var data = Ajax.get('url/data.json');
var elem = document.getElementById('some-div');
Jemplate.process('my-template.html', data, elem);

or simply:

Jemplate.process('my-template.html', 'url/data.json', '#some-div');

or, with Prototype.js:

new Ajax.Request("url/data.json", {
    onComplete: function(req) {
        var data = eval(req.responseText);
        Jemplate.process('my-template.html', data, '#some-div');
    }
);

DESCRIPTION

Jemplate is a templating framework for Javascript that is built over Perl's Template Toolkit (TT2).

Jemplate parses TT2 templates using the TT2 Perl framework, but with a twist. Instead of compiling the templates into Perl code, it compiles them into Javascript.

Jemplate then provides a Javascript runtime module for processing the template code. Presto, we have full featured Javascript templating language!

Combined with JSON and xmlHttpRequest, Jemplate provides a really simple and powerful way to do Ajax stuff.

HOWTO

Jemplate comes with a command line tool call jemplate that you use to precompile your templates into a javascript file. For example if you have a template directory called templates that contains:

> ls templates/
body.html
footer.html
header.html

You might run this command:

> jemplate --compile template/* > js/jemplates.js

This will compile all the templates into one Javascript file.

You also need to get the Jemplate runtime.

> cp ~/Jemplate-x.xx/share/Jemplate.js js/Jemplate.js

Now all you need to do is include these two files in the HEAD of your html:

<script src="js/Jemplate.js" type="text/javascript"></script>
<script src="js/jemplates.js" type="text/javascript"></script>

Now you have Jemplate support for these templates in your html document.

PUBLIC API

The Jemplate.js Javascript runtime module has the following API method:

Jemplate.process(template-name, data, [target]);

The template-name is a string like 'body.html' that is the name of the top level template that you wish to process.

The data can be a object, a function or a url. If it is an object, it is used directly. If it is a function, the function is called and the returned object is used. If it is a url, an asynchronous <Ajax.get> is performed. The result is expected to be a JSON string, which gets turned into an object.

The optional target can be an HTMLElement reference, a function or a string beginning with a # char. If the target is omitted, the template result is returned. If it is a function, the function is called with the result. If it is a string, the string is used as an id to find an HTMLElement.

If an HTMLElement is used (by id or directly) then the innerHTML property is set to the template processing result.

The Jemplate.pm Perl module has the following public class methods, although you won't likely need to use them directly. Normally, you just use the jemplate command line tool.

Jemplate->compile_template_files(@template_file_paths);

Take a list of template file paths and compile them into a module of functions. Returns the text of the module.

Jemplate->compile_template_content($content, $template_name);

Compile one template whose content is in memory. You must provide a unique template name. Returns the Javascript text result of the compilation.

Jemplate->compile_module($module_path, \@template_file_paths);

Similar to `compile_template_files`, but prints to result to the $module_path. Returns 1 if successful, undef if error.

Jemplate->compile_module_cached($module_path, \@template_file_paths);

Similar to `compile_module`, but only compiles if one of the templates is newer than the module. Returns 1 if sucessful compile, 0 if no compile due to cache, undef if error.

AJAX AND JSON METHODS

Jemplate comes with builtin Ajax and JSON support.

Ajax.get(url, [callback]);

Does a GET operation to the url.

If a callback is provided, the operation is asynchronous and the request object is returned. Otherwise, the operation is synchronous and the data is returned.

Ajax.post(url, data, [callback]);

Does a POST operation to the url.

Same callback rules as GET apply.

JSON.stringify(object);

Return the JSON serialization of an object.

JSON.parse(jsonString);

Turns a JSON string into an object and returns the object.

CURRENT SUPPORT

The goal of Jemplate is to support all of the Template Toolkit features that can possibly be supported.

Jemplate now supports the following directives:

* Plain text
* [% [GET] variable %]
* [% CALL variable %]
* [% [SET] variable = value %]
* [% INCLUDE [arguments] %]
* [% PROCESS [arguments] %]
* [% BLOCK name %]
* [% FILTER filter %] text... [% END %]
* [% JAVASCRIPT %] code... [% END %]
* [% WRAPPER template [variable = value ...] %]
* [% IF condition %]
* [% ELSIF condition %]
* [% ELSE %]
* [% SWITCH variable %]
* [% CASE [{value|DEFAULT}] %]
* [% FOR x = y %]
* [% WHILE expression %]
* [% RETURN %]
* [% THROW type message %]
* [% STOP %]
* [% NEXT %]
* [% LAST %]
* [% CLEAR %]
* [%# this is a comment %]

All the array virtual functions are supported:

* first           first item in list
* grep(re)        items matching re
* join(str)       items joined with str
* last            last item in list
* max             maximum index number (i.e. size - 1)
* merge(list [, list...])     combine lists
* nsort           items sorted numerically
* pop             remove first item from list
* push(item)      add item to end of list
* reverse         items in reverse order
* shift           remove last item from list
* size            number of elements
* slice(from, to)     subset of list
* sort            items sorted lexically
* splice(off, len [,list])    modifies list
* unique          unique items (retains order)
* unshift(item)   add item to start of list

Many of the standard filters are implemented.

None of the hash virtual functions are supported yet. Very soon.

None of the string virtual functions are supported yet. Very soon.

The remaining features will be added very soon. See the DESIGN document in the distro for a list of all features and their progress.

BROWSER SUPPORT

Tested successfully in:

* Firefox Mac/Win32
* IE 6.0
* Safari
* Opera
* Konqueror

The top level test harness has a bug in Konqueror, but the individual tests all pass.

DEVELOPMENT

The bleeding edge code is available via Subversion at http://svn.kwiki.org/ingy/Jemplate/

You can run the runtime tests directly from http://svn.kwiki.org/ingy/Jemplate/tests or from the corresponding CPAN or JSAN directories.

Jemplate development is being discussed at irc://irc.freenode.net/#jemplate

If you want a committer bit, just ask ingy on the irc channel.

CREDIT

This module is only possible because of Andy Wardley's mighty Template Toolkit. Thanks Andy. I will gladly give you half of any beers I receive for this work. (As long as you are in the same room when I'm drinking them ;)

AUTHORS

Ingy döt Net <ingy@cpan.org>

Tatsuhiko Miyagawa <miyagawa@bulknews.net>

Yann Kerhervé <yannk@cpan.org>

David Davis <xantus@xantus.org>

Cory Bennett <coryb@corybennett.org>

COPYRIGHT

Copyright (c) 2006. Ingy döt Net. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See http://www.perl.com/perl/misc/Artistic.html

cpanm Jemplate

perl -MCPAN -e shell
install Jemplate