react-jsxrender

JSXRender React component class

react-jsxrender

react-jsxrender is a drop-in React component designed to render simple, static JSX-like markup at runtime.

react-jsxrender is designed to be used with a textarea-like such as CodeMirror, and allow users to produce content containing a mix of regular HTML and custom React components.

Users are given access to a custom environment of React components, but can only set static props, to avoid code injection issues. As long as the exposed components (both HTML elements and React components) are deemed safe, the rendered code will also be safe. Think about it like exposing React components goodness to your users with limited risks. (See, however, the note security at the bottom)

Assume you have defined a component class LoremIpsum which displays dummy text:

/** jsx React.DOM */
var React = require("react");
var LoremIpsum = React.createClass({
    renderfunction() {
        return (
            <div>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin neque nisl, elementum at metus quis, malesuada eleifend dolor. Nunc et feugiat nibh, molestie tincidunt dolor. Nam sodales nisi in urna volutpat tincidunt. Fusce id pharetra neque. Aliquam et feugiat erat. Aliquam posuere tempor venenatis. Pellentesque gravida turpis sollicitudin, laoreet felis a, dignissim enim. Nunc vel vehicula mi. Nulla bibendum malesuada sagittis. Mauris egestas ut nunc sit amet hendrerit.</div>
        );
    }
});
module.exports = LoremIpsum;

Now you want to render a simple markup at runtime such as <div><LoremIpsum /><LoremIpsum /></div> while forbidding <script> and <iframe> tags:

/** jsx React.DOM */
var React = require("react");
var JSXRender = require("jsxrender");
var env = {
    LoremIpsum: require("./LoremIpsum"),
    iframe: null,
    script: null,
};
React.renderComponent(
    <JSXRender env={env} code={"<div><LoremIpsum /><LoremIpsum /></div>"} />,
    document.getElementById("container")
);

A JSXRender components takes 2 props, env and code. env defines a mapping which augments and/or replaces standard React.DOM components. To prevent standard DOM elements from being rendered, simply map their lowercased name to null in env. code resembles jsx markup, but only constant (non-dynamic) props are accepted, i.e. no {magic}. Not a single bit of code will ever be eval-ed, unless of course some components from env explicitly evals its props.

The rendered markup will be wrapped in a <div class='JSXRender'></div>. If for any reason code cannot be rendered, then it will produce instead a <div class='JSXRender JSXRender-error'></div> containing a description of the error. You may or may not style accordingly.

Note that code must respect usual jsx conventions, such as using className instead of class and htmlFor instead of for, special meaning of key, etc.

Note that while no {magic} will occur, usual HTML injection vectors still apply, e.g. you should sanitize code from things like <a href='javascript:alert("injection!");'>, maybe blacklist script, iframe, etc.