UrlReader CKEditor5

urlreader.js

/**
 * @license Copyright (c) 2003-2018, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md.
 */

/**
 * @module upload/urlreader
 */

/* globals window */

/**
 * Wrapper over the native `UrlReader`.
 */
export default class UrlReader {
	/**
	 * Creates an instance of the UrlReader.
	 */
	constructor() {
		this._error = null;
		this._reject = null;
	}

	/**
	 * Returns error that occurred during url featching.
	 *
	 * @returns {Error}
	 */
	get error() {
		return this._error;
	}

	/**
	 * Reads the provided url.
	 *
	 * @param {String} url URL to be read.
	 * @returns {Promise} Returns a promise that will be resolved with  the `File` instance with contents of a given url.
	 * The promise will be rejected in case of an error or when the reading process is aborted.
	 */
	read( url ) {
		return new Promise( ( resolve, reject ) => {
			this._reject = reject;

			window.fetch( url )
				.then( resource => resource.blob() )
				.then( blob => {
					const type = blob.type;
					const filename = `file.${ type.split( '/' ).pop() }`;
					const file = new window.File( [ blob ], filename, { type: blob.type } );

					this._reject = null;

					resolve( file );
				} )
				.catch( error => {
					this._reject = null;
					this._error = error;

					reject( error );
				} );
		} );
	}

	/**
	 * Aborts url reader.
	 */
	abort() {
		if ( this._reject ) {
			this._reject();
		}
	}
}