Scope of localStorage for subdomains

Question

LocalStorage variables are available to any pages retrieved from the same origin. This means that a page can access the local storage variables set by any other page that shares the same scheme (e.g., http, https), domain (e.g., www.example.com), and port (e.g., 80, 443, 8080).

It persists browsers, windows and tabs, but unfortunatelly this does not work for different domains or subdomains. This level of isolation ensures us that we don't accidentally modify any data that other 3rd party sites may have already set in the storage.

But in our case, we need to be able to access some large variables(JSON-objects) persisted by a subdomain.

A workaround for this, as pointed out here, is the use of an iframe in combination with a postMessage. But in my opinion, this is a clumsy and inelegant solution to the problem. Using a cookie will not do the job either, the JSON-objects are too large.

Any other suggestions?

Not sure, but `Access-Control-Allow-Origin` http-header may help you — Maxim Mazurok, Jan 14 '16 at 13:33
Well you could always simply retrieve this object via Websocket or ajax... — Lashus, Jan 14 '16 at 13:33
It seems like I was wrong about CORS: http://stackoverflow.com/questions/20190114/does-cors-affects-localstorage — Maxim Mazurok, Jan 14 '16 at 13:36

score 1 · Answer 1 · answered Jan 14 '16 at 13:34

1

The solution what you have provided in your original post is widely implemented and used in such situations, here are some other alternates which you can try.

answered Jan 14 '16 at 13:34

Thalaivar

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Scope of localStorage for subdomains

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