draft-js-prism is a decorator for DraftJS to highlight code blocks using Prism. It only decorates code blocks with syntax highlighting, if you're interested in providing a correct edition UX for code blocks, take a look at draft-js-code.

$ npm install draft-js-prism prismjs

var Draft = require('draft-js');
var PrismDecorator = require('draft-js-prism');
var Prism = require('prismjs')

var decorator = new PrismDecorator({
  // Provide your own instance of PrismJS
  prism: Prism,
});
var editorState = Draft.EditorState.createEmpty(decorator)

You'll also need to include the css for one of the Prism themes.

You can use this decorator combined with others by using draft-js-multidecorators