Javascript Ajax Graceful-degradation, With Different Pages?

I'm starting to give a little more attention to making my javascript and ajax degrade gracefully. Which is more recommended: working on incorporating the graceful degradation into

Solution 1:

Though it doesn't work well for existing sites, often it's more useful to use the Progressive Enhancement paradigm: build the site so it works with no special add-ons, then start layering your awesomeness on top of that.

This way you can be sure it works from the ground up and everyone (including those who use screen readers, those who turn off images or stylesheets, and those who don't use javascript) can all access your site.

For an existing site, however, it will depend on what functionality the ajax is delivering. In general you should strive to mirror all the ajax functionality with js disabled. If you have security holes in your js version, than you probably will in your non-js version too. AJAX can't get to anything that can't be accessed via ordinary URL.

Solution 2:

Developing two separate sets of pages, one for JS enabled and one for non-JS, is obviously a lot of work, not only initially, but also as your application keeps evolving. If that doesn't bother you too much, I think that's the way to go. I think you are right about same-page graceful degradation being very tricky sometimes. Sometimes this is just because of the layout: With JS enabled, you can simply hide and show elements, where as without JS: where to put everything? Separate sets of pages can help keep page structure cleaner.

About hacking attempts: You can never, never, never rely on client-side JavaScript validation. Everything has to be checked (or re-checked) server-side, and your server-side code may make no assumptions whatsoever on the user input. Therefore, I think the scenario of someone de-activating JS while using the application is irrelevant. Try to keep the expected user input uniform for the non-JS and the JS versions, validate it properly, and you're good.

Solution 3:

You'll probably want to check out jQuery Ajaxy. It lets you gracefully upgrade your website into a full featured ajax one without any server side modifications, so everything still works for javascript disabled users and search engines. It also supports hashes so your back and forward buttons still work.

It's been implemented on these two sites (which I know of) http://wbhomes.com.au and http://www.balupton.com