logi-tpl

A standalone template engine with support for asynchronous content.

About

logi-tpl is a simple but powerful templating system. The way it works is very close to the way PHP is used as a template engine. Full JavaScript functionality can be used inside the templates. See below for more details.

Features

• No other language should be learned. JavaScript is the template language.
• Subtemplates can be included. Different parameters can be passed to them.
• Async content can be inserted wherever needed.

Installation

Installing npm (node package manager)

Installing logi-tpl

Usage

The template engine may work in several convenient ways. The simplest one is this:

var logiTpl = require ('../logi-tpl');
	
logiTpl.applyToFileTemplate (__dirname + '/template.html', {	
	name : 'John Dow',
	age : 21
}, function (error, result) {
    if (error) {
	    console.log ('Error: ', error);			
	} else {
		console.log (result);
    }
});

template.html

Your name is <%= name %>.
<% if (age > 18) { %>
    You are allowed to proceed.
<% } else { %>
    Sorry, you are not allowed to proceed.
<% } %> 

Output:

Your name is John Dow.
You are allowed to proceed.

Instead of providing a file resource, you can directly pass the template as a string and call

logiTpl.applyToStringTemplate (templateCode, params, function (error, generatedContent) {
    /* ... */
}, templateRoot);

If you need to compile a template for a later use, you can do it easily:

logiTpl.compileTemplateCode (templateCode, function (error, compilationResult) {
    /* ... */
}); 

Then use:

logiTpl.applyToCompiledTemplate (compiledScript, params, function (error, generatedContent) {
    /* ... */
}, templateRoot);

The last argument 'templateRoot' can be used when subtemplates are included. When applyToFileTemplate is used, the templateRoot is automatically exctracted from the template file name.

Basic template syntax

In general, if no <% ... %> sections are present, the content is directly returned as it is. The content inside <% and %> pairs is executed as a standard JavaScript. Syntax like the one below is fully valid:

<% if (a > 1) { %>
    some text
<% } %> 

Additionally, content inside <%= and %> is "printed" to the output. There is one special case - if the expression inside <%= ... %> is a function, then this function is expected to provide a content asyncronously. The engine invokes it with a callback parameter and the function should invoke this "callback" with the content passed as an argument. Check example2.js for more details.

Subtemplates are included by using:

<%~ "sub/template.html" %>   

By default, all the parameters are passed to the subtemplate. If you need to pass different parameter set, you can use:

<%~ "sub/template.html", { a : 3, b : 4 } %>   

Planned features

The following things are planned for future releases:

• Improved parsing
• Better parse error details
• Custom compiler options
• New tag pairs like <%& %> for HTML escape and several more.
• Other :)