- From: David Wipperfurth <cobaltbluedw@gmail.com>
- Date: Wed, 14 Jul 2010 12:47:47 -0500
- To: "public-html-comments@w3.org" <public-html-comments@w3.org>
- Message-ID: <AANLkTinBZ1SPe0c839oaEhiTaLmcDbSUl9DLCisqamXH@mail.gmail.com>
Hello, I'm a web app developer whom has tried working with the cache manifest on a larger-end web platform, and I have three concerns that I would hope to get addressed. Hopefully I'm sending this e-mail to the right place... The first, it appears there are only two javascript hooks for manipulating the cache: 'Update' and 'SwapCache'. While it's not clear from the documentation, I assume 'update' merely loads-up a new cache, while 'SwapCache' tells the browser to use that new cache. My main concern is actually the lack of functionality. I would like to see ways of manipulating the cache, changing the manifest file that the browser is using for the cache, removing the cache all together, changing the cache of another page under the same domain, etc. Web platforms will be forced to be quite convoluted if all caching mechanisms have to be handled on the server side, especially, when the whole point of a cache manifest is that the browser is going to limit it's interaction with the server to begin with. The second, a fairly substantial problem, is that as far as I've been able to discern, the html page that the manifest attribute is attached to MUST be cached. Even if you add that html page to the network list, it is unclear as to the expected behavior in that scenario and browsers are likely to still cache the html. This is a major restriction for the cache manifest functionality, because there are certainly many cases where many things on the page SHOULD be cached, but the html document it's self SHOULD NOT. Since the cache manifest must be attached to the root html, there is no way to express what things should be cached if you don't want the root html cached. It would be preferable to either not assume the html page is a master resource, or invent a manifest mechanism to allow the page to be listed as dynamic content. I understand that this would slightly increase the amount of work a browser would have to do to properly load an offline page, but in general even if no one ever wanted to have dynamic html with cached images, styles, and javascript, it would still be a bad idea to force the page that tells you whether it should be cached or not, to be cached. If the server were to change it's mind about wanting that page to be cached, the browser would never know. (That last bit is more of an anecdote, but still...) Finally, a fairly minor concern, but I find it a break-down of standards that the manifest attribute would be attached to the html tag and not it's own meta tag(or other such name/value pair tag) in the header. Sincerely, David Wipperfurth
Received on Wednesday, 14 July 2010 23:05:15 UTC