I am looking at writing a mobile web application with offline support, and would prefer to use the HTML5 offline capabilities instead of something like phonegap.
A requirement of the app will be that it store 2 collections of different types of objects (lets call them Books and Authors) which, when online, it will download from the server. If it didn’t need to be offline then I’d be using some flavour of SQL tables or (preferably) a document-based DB to store these items, but having done some basic investigation I haven’t found anything that feels “right” that works offline.
My question is: what is the best strategy to store those items? What I have considered so far:
HTML5 localStorage – Seems to have relatively wide support but is limited to key value pairs, which would mean a slightly unpleasant data structure – maybe having a total-authors key and then a series of author-1....author-n key-document pairs. This feels wrong to me – like I am trying to work around the intent of the storage.
CouchDb – I’ve worked with CouchDb quite a bit in the past so would love to use it or an equivalent, but “proper” CouchDb would require a native app (with which I have no experience), and the 2 in-browser equivalents I have seen don’t quite seem to do the trick: Lawnchair doesn’t seem to add much to the localStorage option and BrowserCouch doesn’t appear to have had much activity recently (which always makes me wary).
WebDb – Looks like it would be perfect…except it seems to be officially discontinued and doesn’t look to be widely supported
Gears – Discontinued
IndexedDB – Limited browser support for now (at least according to caniuse)
I’m convinced there must be something out there that does what I want, and I’ve just managed to somehow overlook it. Can anyone suggest the way this ought to be done (as opposed to a way it could be done)?
There’s no browser-native simple solution as far I know; you’ll have to either go with localStorage or develop for both WebDB and IndexedDB.
But non-native you could use a abstraction layer like lawnchair (uses localStorage by default, plugins available for indexeddb, webdb, …) or the one SO-user Gatapia wrote for picnet (uses indexeddb & webdb & gears) that you can find on github.