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Does anyone have any advice regarding progressive enhancement for Three js projects on devices?
I have an app with lots of post-processing which is fine on modern devices but a bit slow on older/cheaper phones. It would be nice to enable post-layers progressively for devices that can handle it.
Is there a reasonably reliable way to measure performance so as to automate this?
Welcome to the everyday world of real-time game development on heterogenous devices: PCs, mobiles, or cross-platform consoles...
You might consider simply keeping a list of common hardware profiles. While there are many kinds of phone there are actually very few different GPU architectures used in most all of them. This is the method that has been used by Chrome on Android, for example, to determine which devices work with WebGL and which don't.
I admit that this might seem crude, that there ought to be some clean way to determine which devices will perform well on your code but frankly it will be different for different devices, which is why companies like NVIDIA have test labs that evaluate products against a wide variety of hardware configurations and then they still end up generating some sort of table of performance options for that single game title, rather than building some function that can figure out performance from First Principles.
A few years ago I was scoping-out a system for a game company at which I worked that would measure a range of performance parameters for each individual user and attempt, via regression ("machine learning") to determine the best performance profile for THAT user on THEIR machine because even with a narrow range of hardware choices you still can never tell just how much other stuff is going on on the player's computer. Are they running youtube and teamspeak and who knows what else in the background? Hard to predict the at-home situation, even in a large testing lab. So an adaptive approach might be the best, but even then it is very numerically-intensive and probably not a good fit (today) for javascript-based web apps using THREE.js. So if you want to attack this problem, choose your strategies (drop compositing layers? Opt for simpler geometry? Fewer or simpler shaders? Depends on your app!), try them yourself (experience will trump speculation every time!) , and then start deploying to the public. If your users permit it, ask them to store a cookie. But expect a long iterative process if you really want it to work.
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I hear about it a bit in tutorials that I watch, that certain things won't work if javascript is disabled. Occasionally I see workarounds.
The question is, are these relevent? I can't imagine anyone not having a javascript enabled browser nowadays, except the most ancient of phones, and chances are your page won't render on them properly anyway.
Do people still bother to write backup code for javascript being disabled?
Edit: As a test, I turned javascript off. Facebook doesn't work.
Edit: I understand about visually impaired users, but do people care (harsh, yes) if their experience is buggy? Not to sound disrespectful, but not sticking to strict standards will alienate people using Internet Explorer 4 and 5 too, but we don't seem to care about them...?
Edit: Saying that people should do it seems like a very automatic response, considering how many people use JQuery and other groovy addon libraries.
Edit: I tried a bunch of fortune 500 sites, and so far about 70% of the ones I tried have broken
Dell
Walmart
Fedex
Intel
Coca Cola
Yes, we still need backup code for people who have JavaScript disabled.
JavaScript is often used to do things that break in screen readers (so many screen reader users disable it) or to cause changes to appear out of sight of a screen magnifier.
JavaScript is still one of the biggest attack vectors to exploit security holes in browsers.
Add-ons such as No-Script are increasing in popularity.
Search engines tend not to execute it (so you don't want to hide your content behind it)
I prefer to think of it as a foundation rather than backup.
I understand about visually impaired users, but do people care (harsh, yes) if their experience is buggy?
Nasty people don't.
The law (in many jurisdictions) does.
Not to sound disrespectful, but not sticking to strict standards will alienate people using Internet Explorer 4 and 5 too, but we don't seem to care about them...?
IE 4/5 have:
a smaller market share than users without JS
many security holes
no support from their own publisher
As a developer I no longer worry about 1% of users who turn off Javascript. It is too time consuming and development time is too expensive to waste on such nonsense. AJAX saves an incredible amount of bandwidth which turns directly into $$$ savings, which makes profits higher. If I lose one or two potential users of the site for every 100 users, those one or two lost users will cost a lot more in development than the potential income of they could ever bring in.
Try turning off Javascript and logging into Facebook, it becomes a very broken website after that. If it's good enough for Facebook, its good enough for me.
Support for JavaScript-disabled web sites a nice thought, but not of much help, and of questionable value, IMHO
It is almost impossible to design a robust website without java script, and those that disable JS, for whatever reason, probably don't expect much of a user experience. So if you are coding for that 1% of the population, you have no choice. But for the majority of us, it is a given that JS is there. Accessibility is a different issue, with its own challenges. When I was doing web sites for Hewlett-Packard, they had to meet strict accessibility standards, and it was tough to create anything more than very basic web pages. I wouldn't wish that on anybody.
I have a different opinion to many here. I don't think you necessarily should care in some scenarios, especially if your website is targeting a particular group of people or that it is going to mean a lot of work.
if you refer to:
http://visualrevenue.com/blog/2007/08/eu-and-us-javascript-disabled-index.html
(source: visualrevenue.com)
You can see that year on year more browsers than ever have Javascript enabled, contrary to the other answers' claims. It was at 96.9% in 2007.
So you lose 3% of potential viewers, so what, your advertising campaign will do a lot more damage than that!
Yes. Especially when it comes to 508 and WCAG compliance. While the technologies to create accessible JavaScript are coming out of their infancy (see ARIA), developer's should still be coding sites in a way the does not require JavaScript.
http://www.w3.org/WAI/aria/faq
http://www.w3.org/TR/WCAG10/
All the other questions got most of the points covered, but I'll chime in with this: it's not a big deal to have your page(s) degrade gracefully in the absence of javascript. If you've got some super-whizzy ajax-infested real-time comet style app that really isn't going to work without javascript, you should at least render a nice message to the effect that javascript is required.
It depends on your audience and type of website.
For instance, a graphic artist portfolio will not be visited by blind people or people using text browsers. So in that case it's not so important to build nice degradable JS, expecially because it will most probably be used for graphic effects.
If, on the other hand you're developing a news website and you decide (for whatever reason) to dynamically load your news with JS then you should definitely make it degradable. Also, remember that the spiders of indexing engines may have difficulties in indexing content loaded with JS in your page.
At the end of the day, in most cases it's not so difficult to program the site so that it works without JS. If you're retrieving content dynamically you already have the server-side code to load the content, you just need to accomodate how the page is called.
Same thing for forms, you can send the content via AJAX or via a normal POST, the backend will be pretty much the same, so it's again easy to implement.
Of course, the problem is not even posed for JS code that is purely graphical.
My recent experience:
My former supervisor claimed, in earnest, that because Google Analytics told us that "87% of our users have Java enabled and less than 3% are using IE6," that we didn't have to worry about supporting older browsers or users with JavaScript disabled.
Problem 1: Java is not JavaScript.
Problem 2: In order for Google Analytics to track a hit, the browser must have JavaScript enabled because the GA interface is a JS include. GA is not, and can not, be aware of users with JS disabled, which can potentially severely skew its reports.
Problem 3: one of our biggest customers requires that all engineers use IE6 with JS disabled.
Problem 4: The boss (at the time) didn't know how to read analytics reports.
If you want to know how important this support is to your business, a good place to start is the IIS logs. Just about everything related to the browser caps is stored by IIS. I regularly import the logs into SQL Server and run some basic reports from my admin site, which come in handy every time someone starts suggesting that we go crazy with the jQuery BS.
If you decide to start building complicated, script-dependent interfaces, be sure that your interface degrades gracefully and doesn't remove required functionality if JS is disabled.
It is not merely a question of whether a browser is capable of executing javascript, but if a user has disabled it for some reason.
For example, you need to be aware of vison-impaired users. Such users might disable javascript, because the effects are confusing their screen reader software.
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Closed 11 years ago.
HTML and CSS are showing their age.
SASS generates CSS (because CSS isn't clean enough). Graphic Designers don't work in HTML, they work in graphics tools then have to translate it to HTML/CSS. JavaScript has to have abstractions like jQuery, and CSS has a bunch of hacks to even start approaching consistent predictable user experience.
It feels like people are doing some wonderful things despite the technologies, not because of them.
Surely there is a better way?!? Something more closely aligned with the task at hand.. of providing a fluid intuitive (consistent) user experience to let users achieve their goals.
Thoughts?
Nothing, I believe they are here to stay for next 10 years.
The Internet experience might be enhanced by technologies like Flash & Silverlight but what's valuable about Internet is not the technology but the information.
Therefore, breaking Internet compatibility for pure technological enhancement will never work.
BLTML: Bacon, Lettuce and Tomato Markup Language.
In the future, the web with only be used for posting tasty things we want to eat, so it makes sense to develop a language geared just for this.
The pictures of kittens with words on them will likely be supported with a gross hack .
Graphic Designers don't work in HTML
DTP designers don't produce paper and ink either. Design something and produce something, these are separable tasks - when you have an idea for a tv spot you still need lots of technology between your creativeness and the result, the same applies for the web.
Javascript has to have abstractions
like JQuery, and CSS has a bunch of
hacks to even start approaching
consistent predictable user
experience.
Oh man, js doesn't has to have, developers simply like to make their job easier, this rule applies to various programming languages, it's like saying python has to have django. Frameworks and libraries are over the language, they are not a must.
CSS 'has a bunch of hacks' because some browser producers don't give a damn about something called "standards", not because the language is badly designed.
Surely there is a better way?!?
Something more closely aligned with
the task at hand.. of providing a
fluid intuitive (consistent) user
experience to let users achieve their
goals.
What user experience is not provided with html,css,js? I really don't get your point, and what you expect from the Web.
Oh, and if you are like 'you know, you need flash for something or whatever', start getting interested in canvas.
HTML and CSS are here to stay for a long time yet!
While they may not be as intuitive to use for designers as say PhotoShop, well formed HTML is machine readable - this means that it can be used by humans AND computers. This is very important and useful. Imagine a web full of pictures that look beautiful but cannot be crawled or searched by Google?
HTML and CSS are superior because of the structured information that underlines them.
I don't think that HTML and CSS are showing their age, I think that browsers are showing their age. I like being able to describe what I want done, but not HOW to do it.
I guess what I want is browser vendors to use one rendering engine, or if nothing else, a SSL-type of certification for browsers. Kind of a global impartial body that's measures browsers on a quality bar-like scale.
Just like with SSL certification, it's done by a third party. I'm not sure what the pricing structure would be but I don't think you should have to pay for it. I think that it would make a great "works in this browser" logo like the Spam Free and Mal-ware Free logos we've seen popping up on sites over the years. Or perhaps an Acid1, Acid2, Acid3 passed logos for browsers.
I would argue that libraries like JQuery and Prototype exist because browsers all have their quirks. We just got tired of writing all that handling code, so some very smart people did this for us.
Personally I think HTML and CSS are very elegant, and while the W3C certainly isn't hasty, I think it's probably fair to say that a certain browser has been holding back design on the web more than the technologies themselves.
CSS3 has support for fantastic things such as web fonts with #fontface. Javascript engines are becoming increasingly speedy and allowing for things like John Resig's processing port which would have been unimaginable years ago.
We need to see users adopting new browsers at a faster pace, and we need to see vendors getting behind efforts to encourage their users to upgrade.
I think it's a mistake to think that abstractions are a negative thing, and indicate some problem with the base technology - technologies naturally evolve through abstraction. There's some inconsistency in your post in the sense that you decry the need for abstraction, but then mention that you desire consistency - that consistency across clients is achieved through abstraction. I no longer have to worry about how different clients handle the DOM - jquery does this for me. CSS hacks by the same token aren't really necessary, and it's quite acceptable to serve a different stylesheet to that browser; the rendering difference between the other mainstream engines are pretty minimal.
Please also consider that we're still using a lot of "old" technologies (Unix, c, c++ to name a few), because they are functional, elegant and well designed.
Worse is better. HTML and CSS are never going away because of the large volume of content that's written against that platform. Same thing with C. It's a terrible language, but it will always be with us because nearly all software is written in either C or C++.
A huge volume of JAVA means that's never going away. There's still a market for COBOL programmers.
It's a popular idea among some programmers to get really frustrated at a crufty system like HTML/CSS/JS, and think "Hay, let's demolish it and start over". Well you know, I could invent my own phone that is 100 times better, and with better sound quality than any other phone. That's the easy part. The hard part is having someone to call.
Like it or not, HTML/CSS/JS is the technology trio that became popular, and that means millions of people have invested trillions of dollars in producing content for the technology. Millions of people will be quite reluctant to throw that effort away because someone says HTML/CSS/JS sucks.
It's a mysterious thing figuring out what technology is going to become popular. It's not something you can control for the benefit of your own comfort. But at least, you know, there's such lovely computer science concepts as "abstraction", which if you can master it, will be your secret weapon. Jquery is an example, but it can be taken very much further.
The problem would not be to design something to replace HTML/CSS/JS, but to get browser vendors to adopt it. Good luck with that.
As central as the web experience and HTML are in my life and in your life, the only computer most people in the world use is their phone. The web just doesn't work well even on a multitouch touchscreen.
Just like you no longer enter your game using the ROM basic before playing it, and you no longer see text only screens around (well mostly), some day the web is going to be consumed by specialized devices or by specialized applications for your phone. Machine readable web, or in other words, web services. You can call that web 3.0 if you like.
I believe that the problem is not HTML, CSS and JS or their age (they are constantly evolving anyway). Theoretically you should be able to create one version of something and have it work exactly the same across different platforms. Which is where the problem lies: the platforms.
Saying those technologies are old and therefore need replacing is like saying C++ is old and therefore should not be used for game development. They are actually very appropriate and powerful tools for what they were designed for. Therefore I would predict that its not the HTML, CSS and JS that need to or will be replaced, but that the current platforms need to get their shit together (some more than others) and follow the bloody standards!
That said, they do need to keep evolving to stay relevant.
I think XML with XSL is the future. Graphical designer tools would come with their own XSL stylesheets, tailored to the strengths of the tool, and the tool would generate XML files that use the stylesheets.
But I'm no clairvoyant; what's going to be hot in the next 5 years, who knows. :-P
If you listen to Microsoft, Silverlight will feature prominently in the new web. Since it uses XAML, which is just a text file, it has the potential to be search engine friendly.
Others like Flash.
Of course I am sure that something else new will be invented in the future....
I think RIA's like Adobe flex/air/apollo and Silverlight etc will eat into some of the html market share , but not totally replace it.
Some of the issues that plagued RIA's like SEO related stuff, lack of back button support are being resolved.
The good thing with RIA's is that it is browser independent (as long as the user has the right plugin) , I could foresee future browsers launching with RIA support built-in thereby ensuring a 100% market penetration for apps built using them.
For documents and usual web pages, HTML and CSS are there to stay and evolve (Sass is nice indeed).
For applications, mobile code (javascript most probably) driving canvas-like graphics will help merge web apps and internet-enabled desktop applications.
— I wonder how ridiculous these predictions will look like in 10 years :)
I understand that server-side validation is an absolute must to prevent malicious users (or simply users who choose to disable javascript) from bypassing client-side validation. But that's mainly to protect your application, not to provide value for those who are running browsers with javascript disabled. Is it reasonable to assume visitors have javascript enabled and simply have an unusable site for those who don't?
I browse with NoScript in Firefox, and it always annoys me when I get pages that don't work. That said - know your audience. If you're trying to cater to paranoid computer security professionals - assume they might not have JavaScript enabled. If you're going for a general audience, JavaScript is probably on.
Totally depends on who you're aiming at.
If your site or app is for an Intranet, you can make lots of assumptions. If your target audience is bleeding-edge social-networking types, you can assume JavaScript will work. If you anticipate a lot of paranoia sysadmin types, you can assume a bunch of them will be trying to access your site in lynx or have JS turned of for "security reasons."
A good example of this is Amazon -- their approach is driven by their business goals. They are a mass-market site, but for them, locking out users in old/incapable browsers means potential lost sales, so they work hard on non-script fallbacks.
So like lots of these kinds of questions, the answer is not just regurgitating what you've read somewhere about accessibility or progressive enhancement. The real answer is "it depends."
I think there is another reason which push you to support at least some main functionality without JS - lots of us now browsing from mobile and PDA, which have no the same lvl of JavaScript support.
http://www.w3schools.com/browsers/browsers_stats.asp
They claim 95% of users have Javascript on.
Duplicate
There's at least one category where the answer is definitely "no". If you work for the government, you must make sure the site is accessible to those using screen readers.
Is it reasonable to assume visitors
have javascript enabled and simply
have an unusable site for those who
don't?
There are actually two questions, and the answers are: Yes, it is reasonable to assume visitors have javascript enabled. And, No this does not mean others should be left with unusable site.
Progressive enhancement is the way to go. Have your site usable without javascript and then add bells and whistles.
As for client side validation, it is no more than a convenience for user to avoid unnecessary roundtrips to server (where real validation should be performed).
I browse with the NoScript plugin in firefox and I'm surprised at the amount of developers that haven't even considered making their site degradable.
Never assume the user has JavaScript disabled - especially seeing as it may not always be their fault. Many enterprises have firewalls which block JavaScript/ActiveX etc. - In this instance the <noscript> element won't work so I would NOT recomend using that either!
Unless you're creating a full-on web application which is going to be 90% Ajax then you must make sure to abide by standards and progressively enhance your site through various layers of interactivity.
Also don't forget the important of object detection, especially with the rise of mobile phone web browsing. One of the most popular mobile web browsers (Opera mini 4.0) doesn't allow all "Background javaScript" to work and Ajax calls rarely execute correctly... Just something to be aware of.
To be honest I am sick and tired of developers that think everyone will have JS enabled! What ignorance!!
Yes it is. But expose as much of it as possible through regular HTML and URLs, if for nothing else than for Google.
Accessible, yes... functional? Not really.
This is really a customer requirement question more than developer-answerable, but if your customer tries to enforce a requirement that non-JS browsers work, you should argue heavily against it and really hammer them on the "cool" factor they'll be missing.
Given the heavy reliance by GWT, RichFaces, etc. on Javascript, it's just not feasible to make an app with any kind of user-friendly UI without it.
You should certainly warn non-JS enabled users that the site they're trying to visit relies heavily on JS, though. No point in being rude about it.
It is ok in these days to assume your visitors have JS enabled. With that said, you should strive for the best possible degradation of your site with JS disabled. It is ideal if your site falls back to a state that is still usable without JS.
No! Some environments will have it disabled as a matter of policy, with nothing you can do to enable it. And even if it's enabled, it might be crippled.
This question has been asked before.
One interesting point to consider is that as a web developer you have a social responsibility to push technology forward - and by using things like AJAX, you increase exposure and potentially rate of adoption along with it. The only thing that should stop you from using the tech to its fullest extent is money - if you won't make the money that you need because people will have trouble viewing the material, you've got to reconsider.
Never ever assume Javascript for form validation, as your question implies. Someone will eventually realise this and turn Javascript off.
Instead, code the app in fairly regular html manner and use Javascript for what it is: an optional perk for your users.
Even for an entirely AJAX app like Gmail, the complete works of form validation is required on the server side.
Yes it is, JavaScript is as old as CSS and no one tries to build around browsers that don't support CSS. Cross Site Scripting is the reason people are afraid of JavaScript, but believe me if a developer wants to screw you over he doesn't need JavaScript to do it. As far as mobile browsers, most of them now have JavaScript, and the others shouldn't be considered browsers. My advice is not to open yourself to hackers by making your site vulnerable to those who choose to turn off their JavaScript, but at the same time don't go out of the way to support those who are living in the stone age. You aren't going to support IE 4 or Netscape, right? Then why support those who sabotage their own browsers because of blatant fear or paranoia?
I think it's fair to assume that the majority of visitors to your site will have JavaScript enabled. Some of the more trafficked sites out there have a dependency on JavaScript. For example, I was surprised to learn that you can't authenticate through a Passport-enabled site without a JS-enabled browser.
Nearly all (but not quite all!) users will have javascript enabled. (I believe the figure quoted above of about 5% is accurate.)
Given the vast improvement in usability you can make with the judicious use of javascript, my opinion is that most of the time, it is reasonable to assume it is enabled.
There will of course be some instances where that is not the case, (ie, a site designed for mobile devices, or with a high percentage of disabled users etc), and always a effort should definitely be given to making your site as accessible as possible to as large a percentage of the population as possible.
That said, if you only have a low traffic site, 5% of a small number is a very small number. It may not be worth bending over backwards to make your site accessible to these people when it may only gain you one or two extra users.
I guess the short answer is (as always), there is no correct answer - it will depend entirely on the target use, and target users of the sit in question.
According to this little page Javascript is enabled in 95% of browsers and it keeps raising.
The W3C Browser Statistics page (scroll down) has some information on this; they say that 95% of visitors have JavaScript on as of January 2008.
It's reasonable to assume your visitors have javascript enabled !-)
-- but of course it depends on who you're trying to reach ...
Several times above w3schools have been mentioned and, as Dan stated, its their own visitors which make it somewhat quirky to draw conclusion from.
However, if you look at theCounter.com it seems that their audience has the same habits in general on this point ...
A twist that hasn't been mentioned yet is the growing amount of crawlers, mailharvesters and so on, they definitely do not have javascript turned on, and how good are counters to detect them ?-)
My guess would be, that this sort of machine-browsers fill up a lot of those 5-6% !o]
-- that said, if it's at all possible, make your app degrade gracefully (as a wise man said)
Your questions seems to suggest form based input for an application. If it's an intranet application then you'd be guided by the in-house security experts. If it's public app, then as other posters have suggested, fail gracefully.
I will argue that it is more than reasonable to expect them to have javascript so long as you provide suitable means to replace javascript should it not be enabled. One of the reasons that I like the Yahoo UI Library is that it degrades gracefully.
I always try to code my sites as static one first, THEN i add js/ajax functionality. This way i can be kinda sure that will work on non JS browsers :)
But, javascript is like flash: all users have it, but developer have to concern on WHAT IF.... ? :D
No its not, period, full-stop, end of story. Its just naive and wrong at an ethical level, not to mention you miss out on around 50% of Internet users worldwide (believe it or not 70% of web access worldwide is from mobile devices).
Add extra nifty stuff that requires Javascript, thats fine. Don't make your site unusable without Javascript unless you have really, really, really good reason to do so.
Someone rightly pointed out that I don't have evidence to back up my claim of 70% mobile web users. Unforunately I can't find the source I got it from but I remember it being authorative so have no reason to doubt it. It does make sense though when you consider worldwide usage, many developing countries have more mobile phones than landlines and broadband. A statistic that was quoted in my not-to-be-found source was that one African country in particular has 300,000 landlines, but has 1.5 million mobile phones!
This is totally a "it depends" question, as many people have pointed out.
This is why metrics is valuable on sites to help show if you can really run with the analogy that "major sites say that the majority of people have JS on" - you could have a site where it's 99%.
I won't dig in to what's been said above, as it's been answered very well :)
Not that everyone else hasn't chimed in, but I disagree with the "look at your audience" position to some extent.
It really should be "look at your app" if you are just displaying some information, and your js is for bell/whistle purposes, then certainly look at nice degradation, if you want to.
However, if you're building something like Google Docs, it's really asinine that someone would think they could use your site without js, so perhaps let them know that via a nice sarcastic message inside <noscript> tags.
From a purely philosophical point of view, if users want to access your site, they will flip the js switch, or upgrade to a decent browser, etc. And you should force them to do this, because evolution is important for the survival of the species.
According to this site, 95% of browsers use JavaScript.
That said, there are a LOT of bots that don't use JavaScript: scrapers, search bots, etc. I'd say closer to 100% of actual human users use JavaScript. But your guess is just as good as mine.
Is it alright to expect that the user using the back end will have Javascript enabled?
I guess the answer I'll get is 'it depends on your target users'. I am developing a system for fun that will hopefully be used by other people. I would like to hear from other people developing back end systems, and what did they decide to do and why?
SEO I'm not concerned with, and semantics aern't of as much importance.
Personally I would expect the failover, but there are circumstances (particularly low profile sites, intranets, e-learning content) where you can assume JS.
Mostly you can even go with a simple "You require JS / This works better with JS" and I would consider that good enough, but there's a couple of instances where I would demand real failover:
.gov or other public service sites (legal requirements)
sites for web-tech companies (you need to demonstrate your ability to do this)
very high traffic sites (where the 3% of non-JS users becomes a high absolute number)
sites (or pages) for mobile devices (most of these haven't got JS reliably)
In general, it's reasonably easy to provide some kind of noscript, so why not do it anyway?
if its for fun please go ahead and require javascript.
considering the 3 points :
backend means only a few people will be accessing them (and all of them probably have knowledge about web too, eg. know what javascript is and how to get it enabled)
SEO isn't important
it's for fun
I'd say that it's alright. :)
annakata provided a pretty good insight as well.
It really depends on your application and its target audiences. Do you care about user accessibility (can disabled people use the site), do you want your site to work on various mobile browsers with limited JavaScript support? I would try to build the site so that it would gracefully degrade without CSS or JavaScript. That is unless you site is very dynamic, like say a word processor which can't possible work at all without JavaScript.
Yes, It mostly depends on your target user.
Whatever the front end is, the back end must be bulletproof.
At least, it should make ensure that, nobody can hack or make a mess by disabling javascript.
server-side filtering/validations is important for security, while client-side validation and interactivity is important for usability.
I don't think it's unreasonable to require Javascript for a web based backend/CMS, where your target users are likely to be a fairly small and pretty specific group.
All the CMS systems that I've worked on so far have required it.
I refer you to this post by Jeff Atwood. The important assertion in it is that you can expect that javascript will work as expected among browsers. The security risks are also lower today. So I would say that is now safe to ignore clients that do not enable javascript. If you want to attack users javascript would give a clear advantage.
The only exception I can think of is mobile sites. Although mobile browsers have gone better and do support javascript, the extra download bandwidth and the small screen make js less suitable.
As long as the function that your application will be serving is general, I'd say it is safe to rely on Javascript. One of the sites that I manage receives ~35,000 UV's on a good day. I think it is fair to say we come in contact with quite a variety of browser and operating system combinations. According to our stats, roughly 97% of our users have Javascript enabled.
If it can fail elegantly without Javascript, I'd opt for that solution, but I wouldn't lose sleep over the fact that you might be losing a few people everyday.