webpack/lib/schemes/DataUriPlugin.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

const NormalModule = require("../NormalModule");

/** @typedef {import("../Compiler")} Compiler */

// data URL scheme: "data:text/javascript;charset=utf-8;base64,some-string"
// http://www.ietf.org/rfc/rfc2397.txt
const URIRegEx = /^data:([^;,]+)?((?:;[^;,]+)*?)(?:;(base64))?,(.*)$/i;

const decodeDataURI = uri => {
	const match = URIRegEx.exec(uri);
	if (!match) return null;

	const isBase64 = match[3];
	const body = match[4];
	return isBase64
		? Buffer.from(body, "base64")
		: Buffer.from(decodeURIComponent(body), "ascii");
};

class DataUriPlugin {
	/**
	 * Apply the plugin
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		compiler.hooks.compilation.tap(
			"DataUriPlugin",
			(compilation, { normalModuleFactory }) => {
				normalModuleFactory.hooks.resolveForScheme
					.for("data")
					.tap("DataUriPlugin", resourceData => {
						const match = URIRegEx.exec(resourceData.resource);
						if (match) {
							resourceData.data.mimetype = match[1] || "";
							resourceData.data.parameters = match[2] || "";
							resourceData.data.encoding = match[3] || false;
							resourceData.data.encodedContent = match[4] || "";
						}
					});
				NormalModule.getCompilationHooks(compilation)
					.readResourceForScheme.for("data")
					.tap("DataUriPlugin", resource => decodeDataURI(resource));
			}
		);
	}
}

module.exports = DataUriPlugin;