html-template-tag

ES6 Tagged Template for compiling HTML template strings.

Installation

This package is distributed via npm:

npm install html-template-tag

Usage

String Interpolation

At its core, this module just performs simple ES6 string interpolation.

var html = require("html-template-tag");
// - or - import html from "html-template-tag";

var name = `Antonio`;
var string = html`Hello, ${name}!`;
// "Hello, Antonio!"

Nevertheless, it escapes HTML special characters without refraining its use in loops!

var html = require("html-template-tag");
// - or - import html from "html-template-tag";

var names = ["Antonio", "Megan", "/><script>alert('xss')</script>"];
var string = html`
  <ul>
    ${names.map((name) => html` <li>Hello, ${name}!</li> `)}
  </ul>
`;
// "<ul><li>Hello, Antonio!</li><li>Hello, Megan!</li><li>Hello, /&gt;&lt;script&gt;alert(&#39;xss&#39;)&lt;/script&gt;!</li></ul>"

Skip autoscaping

You can use double dollar signs in interpolation to mark the value as safe (which means that this variable will not be escaped).

var name = `<strong>Antonio</strong>`;
var string = html`Hello, $${name}!`;
// "Hello, <strong>Antonio</strong>!"

HTML Template Pre-Compiling

This small module can also be used to pre-compile HTML templates:

var html = require("html-template-tag");
// - or - import html from "html-template-tag";

var data = {
  count: 2,
  names: ["Antonio", "Megan"],
};

var template = ({ names }) => html`
  <ul>
    ${names.map((name) => html` <li>Hello, ${name}!</li> `)}
  </ul>
`;

var string = template(data);
/* 
	"
	<ul>
		<li>Hello, Antonio!</li>
		<li>Hello, Megan!</li>
	</ul>
	"
*/

NB: The formating of the string literal is kept.

Interpolation inside URI attributes

To avoid XSS attacks, this package removes all interpolation instide URI attributes (more info). This package also ensures that interpolations inside attributes are properly escaped.

If you want to interpolate inside a URI attribute, you need to skip autoescaping (make sure that the string is safe!):

var url = "https://www.example.com/test=1234&54>6";
var string = html`<a href="$${html`${value}`}">link</a>`;
// "<a href="https://www.example.com/test=1234&amp;54&gt;6">link</a>"

Note that $${html`${value}`} isn't strictly necessary, but it allows the escaping of characters in the string inside the URI attribute. You could technically just use $${value} but make sure that value is properly escaped!

License

MIT

Thanks

The code for this module has been heavily inspired on Axel Rauschmayer's post on HTML templating with ES6 template strings and Stefan Bieschewski's comment.