αtαt

Fast and simple asynchronous JavaScript template engine without dependencies and for any environment (:

But why?

I wanted to create something simple for what you don't need to spend hours to read the documentation, something that you can start to use in a few minutes. The main idea is using pure JavaScript with pure HTML. You don't need to learn new syntax, just do everything like in JavaScript.

Features

• Embedded JavaScript code
• Browser support
• Complies with Express
• Layouts, partials and sections
• No dependencies and very small size
• TypeScript support
• Easy to use

Installation

Using yarn or npm:

$ yarn add atat
$ npm install --save atat

Tests

Using yarn or npm:

$ yarn test
$ npm test

Usage

import { config, parse, loadAndRender, render, loadAndParse } from 'atat';

var atat = require('atat');

atat object has the following methods

• config to setup global configuration for all templates
• parse to parse a template, returns a render function
• loadAndParse the same with parse but allows a path to a template as the first argument
• render to parse and render a template, returns the result string
• loadAndRender the same with render but allows a path to a template as the first argument

import { parse, loadAndRender, render, loadAndParse } from 'atat';

const render = await parse(templateString, options);
container.innerHTML = render(model);

container.innerHTML = await render(templateString, model, options);

const render = await loadAndParse(pathToTemplate, options);
container.innerHTML = render(model);

container.innerHTML = await loadAndRender(pathToTemplate, model, options);

If your environment doesn't support async/await sytax, use Promise

render(templateString, options).then((err, result) => {
  container.innerHTML = result;
});

Options

• it models variable name, default "it"
• $ helpers variable name, default "$"
• helpers extra helpers
• loader templates provider

import { parse, render, config, DEFAULT_LOADER } from 'atat';
const options = {
    it: "it",
    $: "$",
    helpers: { },
    loader: DEFAULT_LOADER
};

// global config will be applied to all templates
config(options);

// also you can pass options to the parse and render methods
const tmpl = await parse(templateString, options);
const html = await render(templateString, { /* model */ }, options);

Loaders

Loaders allow you to load templates asynchronously. There are two default loaders available right from the library:

• DEFAULT_LOADER - for Node.js, default loader, uses fs module
• FETCH_LOADER - for a browser, loads templates through fetch method

import { loadAndRender, loadAndParse, config, FETCH_LOADER, DEFAULT_LOADER } from 'atat';

const html = await loadAndRender(
  path.resolve(__dirname, './views/main.html'),
  { /* model */ },
  { loader: DEFAULT_LOADER },
);

// in a browser you must specify loader, at least FETCH_LOADER
const html = await loadAndRender(
  'http://localhost:3000/views/main.html',
  { /* model */ },
  { loader: FETCH_LOADER },
);

// custom loader
config({
  loader: async (path) => {
    const template = await loadTemplate(path);
    return template;
  }
});

Syntax

Encoded output

<p>@(it.user.firstName)@</p>

<!-- 
  Model: { user: { firstName: 'Charlotte' } }
  Output:
  <p>Charlotte</p>
 -->

Raw html output

<p>@!(it.rawHTML)@</p>

<!-- 
  Model: { rawHTML: '<i>Hello!</i>' }
  Output:
  <p><i>Hello!</i></p>
 -->

Embedded JavaScript code

@{
  // Any JavaScript code is acceptable in this block
  var firstName = it.user.firstName;
  var secondName = it.user.secondName;
}@

<p>@(firstName)@ @(secondName)@</p>

<!-- 
  Model: { user: { firstName: 'Charlotte', secondName: 'Gamboa' } }
  Output:
  <p>Charlotte Gamboa</p>
 -->

@if

@if (it.user != null) {
<p>@(it.user.firstName)@</p>
<p>@(it.user.secondName)@</p>
}@

<!-- 
  Model: { user: { firstName: 'Charlotte', secondName: 'Gamboa' } }
  Output:
  <p>Charlotte</p>
  <p>Smith</p>
 -->

@if...else if...else

@if(it.user && it.user.firstName && it.user.secondName){
<p>@(it.user.firstName)@</p>
<p>@(it.user.secondName)@</p>
} else if (it.user && it.user.firstName) {
<p>@(it.user.firstName)@</p>
} else {
<p>User is not defined</p>
}@

<!-- 
  Model: { user: { firstName: 'Charlotte', secondName: '' } }
  Output:
  <p>Charlotte</p>
 -->

@for

<ul>
  @for(var i = 0, l = it.users.length; i < l; i++){
  <li>@(it.users[i].firstName)@ @(it.users[i].secondName)@</li>
  }@
</ul>

<!-- 
  Model: { users: [{ firstName: 'Charlotte', secondName: 'Gamboa' }] }
  Output:
  <ul>
    <li>Charlotte Gamboa</li>
  </ul>
 -->

@while

<ul>
  @{ var i = 0, j = 5; }@
  @while (i < j) {
  <li>@(i++)@</li>
  }@
</ul>

<!-- 
  Output:
  <ul>
    <li>1</li>
    <li>2</li>
    <li>3</li>
    <li>4</li>
    <li>5</li>
  </ul>
 -->

Helpers

Custom helper

@<name>(<args...>)@

• name the valid name
• args... whatever you want

const options = {
    $: '$',
    helpers: {
      l10n: (lang, key) => resources[lang][key];
    }
};

const result = await atat.render(template, { lang: 'en' }, options);

<title>@l10n(it.lang, "title")@</title>
<title>@('My Website - ' + $.l10n(it.lang, "title"))@</title>

<!-- 
  Model: { lang: 'en' }
  Output:
  <title>Main page</title>
  <title>My Website - Main page</title>
 -->

Default helpers

• @json(<object>)@ returns a result of JSON stringify
• @encode(<string>)@ the same as @(<string>)@
• @join(<array>, <separator>)@ joins the array with the separator (optional)
• @upper(<string>)@ simple uppercase
• @lower(<string>)@ simple lowercase

Layout

@layout(<path>)@

• path the path to the layout file

index.atat

@layout('/views/_layout.atat')@
<div class="page-container">
  Home page!
</div>

/views/_layout.atat

<html>
  <head></head>
  <body>
    <main>
      @!(body)@
    </main>
  </body>
</html>

Output:

<html>
  <head></head>
  <body>
    <main>
      <div class="page-container">
        Home page!
      </div>
    </main>
  </body>
</html>

Patrial

Patrials allow you to reuse useful pieces of code in different places

@partial(<path>, <model>)@

• path path to partial a view file
• model model for a partial view (optional)

views/_menu.atat

<nav role="main">
  <ul>
    <li>
      <a href="/" class="@(it.page=='home'?'active':'')@">Home</a>
    </li>
    <li>
      <a href="/about" class="@(it.page=='home'?'active':'')@">About</a>
    </li>
  </ul>
</nav>

views/_layout.atat

@{ const { $route } = it; }@
<html>
  <head></head>
  <body>
    @partial('/views/_menu.atat', $route)@
    <main>
      @!(body)@
    </main>
  </body>
</html>

Output:

<html>
  <head></head>
  <body>
    <nav role="main">
      <ul>
        <li>
          <a href="/" class="active">Home</a>
        </li>
        <li>
          <a href="/about" class="">About</a>
        </li>
      </ul>
    </nav>
    <main>
      <!-- Home page content -->
    </main>
  </body>
</html>

Section

Section allows you to pass HTML markup from a view to a layout level

Use the following syntax to specify a new section

@section script {
<script>
  document.addEventListener('DOMContentLoaded', function() {
    // your code is here
  });
</script>
}@

and another one to output the result anywhere

@section(<name>)@

• name sections name

index.atat

@layout('/views/_layout.atat')@
<div class="page-container">
  Home page!
</div>
@section script {
<script>
  document.addEventListener('DOMContentLoaded', function() {
    // your code is here
  });
</script>
}@

/views/_layout.atat

<html>
  <head></head>
  <body>
    <main>
      @!(body)@
    </main>
    @section('script')@
  </body>
</html>

Output:

<html>
  <head></head>
  <body>
    <main>
      <div class="page-container">
        Home page!
      </div>
    </main>
    <script>
      document.addEventListener('DOMContentLoaded', function() {
        // your code is here
      });
    </script>
  </body>
</html>

ExpressJS Integration

Just set 'view engine' value to atat

const express = require('express');

const app = express();

app.set('views', './views');
app.set('view engine', 'atat');

Example available here

Demo

Live demo

License

The JavaScript Templates script is released under the MIT license.