Save and track reading progress

[rayssafs]

Hello, I would like to know if there is a way to save and track the reading progress, without saving this information in local storage/ browser. For example, if the users use the reading channel in different devices, they should be able to start on the same page they stop the reading.

[danielweck]

The functionality you are describing is currently not implemented, but you can of course replace the LocalStorage code with an alternative method. There is currently no "extensibility" API to introduce such feature, so you would have to modify the existing code.

From the top of my head, I would suggest looking into the savePlace() function:

readium-js-viewer/src/js/EpubReader.js

Lines 758 to 791 in a9f48eb

	var savePlace = function(){
	var bookmarkString = readium.reader.bookmarkCurrentPage();
	// Note: automatically JSON.stringify's the passed value!
	// ... and bookmarkCurrentPage() is already JSON.toString'ed, so that's twice!
	Settings.put(ebookURL_filepath, bookmarkString, $.noop);
	if (!isChromeExtensionPackagedApp // History API is disabled in packaged apps
	&& window.history && window.history.replaceState) {
	var urlParams = Helpers.getURLQueryParams();
	var ebookURL = urlParams['epub'];
	if (!ebookURL) return;
	ebookURL = ensureUrlIsRelativeToApp(ebookURL);
	var bookmark = JSON.parse(bookmarkString) || {};
	var epubs = urlParams['epubs'];
	var gotoParam = generateQueryParamCFI(bookmark);
	var url = Helpers.buildUrlQueryParameters(undefined, {
	epub: ebookURL,
	epubs: (epubs ? epubs : " "),
	embedded: " ",
	goto: {value: gotoParam ? gotoParam : " ", verbatim: true}
	});
	history.replaceState(
	{epub: ebookURL, epubs: (epubs ? epubs : undefined)},
	"Readium Viewer",
	url
	);
	}
	};

...more specifically reader.bookmarkCurrentPage() and Settings.put() which you could use as a hook / extension point for your distributed / remote storage facility:

readium-js-viewer/src/js/EpubReader.js

Lines 760 to 763 in a9f48eb

	var bookmarkString = readium.reader.bookmarkCurrentPage();
	// Note: automatically JSON.stringify's the passed value!
	// ... and bookmarkCurrentPage() is already JSON.toString'ed, so that's twice!
	Settings.put(ebookURL_filepath, bookmarkString, $.noop);

readium-js-viewer/src/js/storage/Settings.js

Lines 23 to 36 in 4ab8dab

	Settings = {
	put : function(key, val, callback){
	if (!isLocalStorageEnabled()) {
	if (callback) callback();
	return;
	}
	var val = JSON.stringify(val);
	localStorage[key] = val;
	if (callback){
	callback();
	}
	},

I hope this helps.