Save callback should not be executed while the previous wasn't resolved

[Reinmar]

I wrote such a simple sample:

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

/* globals ClassicEditor, console, window, document, setTimeout */

import { CS_CONFIG } from '@ckeditor/ckeditor5-cloud-services/tests/_utils/cloud-services-config';

ClassicEditor
	.create( document.querySelector( '#snippet-autosave' ), {
		cloudServices: CS_CONFIG,
		toolbar: {
			viewportTopOffset: 60
		},
		autosave: {
			save( editor ) {
				return saveData( editor.getData() );
			}
		}
	} )
	.then( editor => {
		window.editor = editor;
	} )
	.catch( err => {
		console.error( err.stack );
	} );

function saveData( data ) {
	return new Promise( resolve => {
		log( `Saving... (${ data })` );

		setTimeout( () => {
			log( 'Saved.' );

			resolve();
		}, 1500 );
	} );
}

function log( msg ) {
	const console = document.querySelector( '#snippet-autosave-console' );

	console.textContent = msg + '\n' + console.textContent;
}

<div id="snippet-autosave">
	<p>TODO</p>
</div>

<pre id="snippet-autosave-console"></pre>

It behaves like this now:

IMO, it should wait with the next "Saving..." until the previous save attempt was completed.

It isn't a big deal if it doesn't wait, but it's odd. It wasn't natural for me.

[Reinmar]

Adding to the next iteration, but it'd be good to get some feedback what's the expected behaviour. We can also check some other implementations.

[wwalc]

it should wait with the next "Saving..." until the previous save attempt was completed.

Just a note that if we ever implement this, we should handle correctly a situation where the first save attempt failed (not sure what was the definition of "completed" above). We should try to continue saving the data again after getting an error/timeout or sth.

[pjasiun]

Just a note that if we ever implement this, we should handle correctly a situation where the first save attempt failed (not sure what was the definition of "completed" above). We should try to continue saving the data again after getting an error/timeout or sth.

We agreed to handle errors in the separate ticket. In this ticket, we should focus not to execute another save action before the previous one finish.