how to prevent css and js being cached by internet service provider? - css

I got "dump" isp that always cached internet pages and its css for at least 1 day.
Although the css / js in the server changed, the presented css are not changed (i have been clear my cache everytime)
how to "tell" my isp not to cache some files like css and js ?
thank you !!
at the moment: i'm using proxy to check a under developed web so that it don't get cached ..

The way Stack Overflow itself solves this problem is to add a version parameter to the CSS and JS URLs, which refer to the version of the referenced files:
<link rel="stylesheet" href="http://sstatic.net/so/all.css?v=4542">
Every time the referenced files change, the href attribute of the link tag is updated in the HTML code, thus supporting caching and updated referenced files.

You could try to append some random string to every request of an external file like:
<link href="/css/style.css?cachekiller=1337" media="screen" rel="stylesheet" type="text/css" />
where the 1337 in the above code should be generated randomly for every request e.g.
<?php time() ?>
or something

You can include these documents directly in your HTML files, between <script> or <style> tags. It will obviously make all your HTML files bigger, but that's basically what you're asking.
It's the only way you can be 100% sure that your CSS and JS is not cached at all.

Related

accessing the CSS in browser using question mark (?) in end

can someone explain what is the difference in accessing CSS in browser by putting question mark ? in the end and why the new CSS is not making any affects on Website.
I have deployed a new CSS on web server but its not making any affect.
I tried to open the URL in browser as below:
www.mysite.com/styles/css/main.css
and it loads the older version of CSS.
Then I tried it as below and it loads the new version of CSS.
www.mysite.com/styles/css/main.css?
After doing all this. New CSS change does not affecting the website. Its still displaying the old design.
Kind Regards
You need to add something after the ? then change it when you change the CSS. What is happening is a browser will cache anything that doesn't change for a specific period, it does that by checking file names. so main.css? is still main.css? Anything after the question mark is a query string, generally it's used to pass data to a particular file. In this case it's just used to change the file string so the browser will update it every time it changes without affecting the file itself.
There are a couple of ways you can handle this, the first is manually changing the version, probably the easiest idea if you have a single header file, as in a template system that always loads the same head data.
<link rel="stylesheet" type="text/css" href="assets/css/main.css?ver1/>
Then on next change:
<link rel="stylesheet" type="text/css" href="assets/css/main.css?ver2/>
If you'd rather do it automatically you can add a bit of PHP script to the css line like this:
<link rel="stylesheet" type="text/css" href="assets/css/main.css?time=<?php echo filemtime('./assets/css/main.css');?>" />
This is essentially adding a value that changes every time you save the file and results in something like this, the next time I save the file that time= value will change:
<link rel="stylesheet" type="text/css" href="http://localhost/refficient/trunk/assets/css/main.css?time=1350305706" />
browser cache is the reason,Adding ? after css is not recommended.Open your hosting space and clear cache and thread pool as well.

Shopify: Can't load external stylesheet from another server

https://friends-with-you.myshopify.com/
I'm trying to develop my first shopify theme. I'm trying to load a stylesheet which is hosted on another server, but the CSS is not loading. If I copy and paste that CSS directly into a file in the shopify theme, it works.
<link type="text/css" rel="stylesheet" href="http://fwy.pagodabox.com/magic/themes/fwy/fwy.css" />
What am I doing wrong at the above URL, and why isn't the css loading?
thanks!
Can you load your CSS file over both http and https? If so, change your tag to look like this:
<link type="text/css" rel="stylesheet" href="//fwy.pagodabox.com/magic/themes/fwy/fwy.css" />
That way whether a user visits using http://yourstore.com or https://yourstore.com, they'll get the stylesheet served using the protocol they're on (and you won't get any mixed content warnings).
A little more background: http://paulirish.com/2010/the-protocol-relative-url/
Under IE7 and IE8, using this in a <link> tag will result in your content being fetched twice.
Change your link tag to use a secure URL:
<link type="text/css" rel="stylesheet" href="https://fwy.pagodabox.com/magic/themes/fwy/fwy.css" />
^
The URL you're using now works fine on its own, but since you're browsing to the Shopify store over SSL, many web browsers are going to be hesitant to load the CSS over an unsecured connection.
I just checked and pagodabox serves the CSS file just fine over SSL.
In normal HTML documents one can load stylesheets from anywhere, as long as they exist and you're able to load them by typing the URL in (which I can).
I see the page as two navigation bars with a logo on the left hand side. There are hover states with transitions to a colour background on each item. Although, when I loaded the page, Chrome warned me not to load supposedly insecure content. Before this is loaded I just see text in Times New Roman. I think this is you problem.
I use themes with WordPress and style-sheets come with them (mostly). I don't see why you couldn't just put the style-sheet in with the rest of the theme.
Overall, the answer is yes (normally) but in this case browsers may regard it as un-safe and therefore not load it.
Yes you can! But it is faster to host the stylesheet on your server/where the other files reside. If you plan to include a stylesheet from elsewhere, you could run into problems of that server being down/busy and hence your theme will not display as required. As #Blieque mentioned, some browsers may question external content causing unnecessary warning popups to a user/user-agent.

django css file cached

I'm having a css file and i want to modify it to fit my needs.
The problem is that it seems to be cached somewhere, as i just cannot see the changes, no matter what i do in the css file.
I am sure i am pointing to the right file, as by now i'v modified in it, and it worked.
Is there any setting so that i can turn the cache off?
Thanks!
As pointed out in this article http://www.wkoorts.com/wkblog/2009/07/12/css-auto-reload-with-django-templates/, you could force django reload your css file by using a parameter in your css link :
<link rel="stylesheet" type="text/css" href="/site_media/css/style.css?{% now "U" %}" />
This is a timestamp which takes a different value every second, so you could even reload your css second every second if needed!
Just go into your site, view source, and copy the link to your CSS file. Verify the link, verify it's being modified. Refresh the CSS file manually via your browser to get the latest.
This isn't a Django issue.
Did you try appending a datetime stamp to the end of the request? I know some frameworks do this to .js and .css files automatically to prevent caching.
Instead of using complicated solutions you can add extra parameter to your includes in the templates.
For static includes:
<script src="{% static 'js/polls/polls.js' %}?version=1"></script>
For direct includes:
<link rel="stylesheet" type="text/css" href="/site_media/css/style.css?version=1" />
Note the ?version=1 in the code. Every time you're modifying the file, change this version in the template, so browser will be forced to reload the file.
Of course you can use even now as suggested by #rom, but if your static files are not being changed very often, it's not the smartest idea to don't use cache at all.

Problems referring a css from an XHTML

In my JSF Application (My faces 1.2.3) , I am referring to a css file as
<link href="css/nav.css" type="text/css" rel="stylesheet" />,
This worked when the rendered HTML is accessed as an HTML file using the browser but not inside my customized servlet container.
It wasn't referring correctly, eventhough the relative path was correct. Then I tried with
<link href="../css/nav.css" type="text/css" rel="stylesheet" />
It worked in a browser and did not in some other browsers.
I was told that I should use facelets.DEVELOPMENT" = true to make it work , It worked in Dev Env and it did not in Test Env (There will be some inherited properties!!! and not everything will be used from my application)
I have some knowledge on these accompanying technologies but not an expert. Wondering whats the issue and where ? - Servlet Container , XHTML , Facelets , JSF Impl ?
Any Idea - What could be the problem?
A relative <link> URL is relative to the request URL as it is on the client side, in the webbrowser's address bar (the webbrowser is namely the one responsible for loading the CSS files), it is not relative to the folder structure as it is on the server side.
So if the request URL is for example http://example.com/context/page.jsf, then the CSS which is referenced by href="css/nav.css" will be loaded by http://example.com/context/css/nav.css and the CSS referenced by href="../css/nav.css" by http://example.com/css/nav.css.
If you still stucks with this, then you need to post both the absolute URL with which you can request the page in question successfuly and the CSS file itself. This way we can explain you which relative URL to the CSS file you should be using for the page in question.
Probably the problem is that your application is not absolute to the request url
Lets assume that you access your application via:
http://localhost/my-app/
And now when you try to load a resource as you described above
<link href="css/nav.css" type="text/css" rel="stylesheet" />
It will be loaded by
http://localhost/css/nav.css
I would suggest using the context path property when referring resources.
<link rel="stylesheet" type="text/css" href="#{request.contextPath}/css/style.css"/>
One potential solution here would be to use a root relative path, something like.
/MyCSSFolder/myfile.css
In most cases this can resolve the issues.

css file not getting updated

the font of the content of my facebook app keeps getting italicized even when i've removed the italics from the css file. if i make minor changes in the css file and upload it to the server, the firebug shows the unedited previous css file and hence, the app keeps showing unformatted content. what exactly is going wrong here?
i made a new css file and copied the contents of the previous css exactly as it was, and i linked it in all the files which require css. but when i upload these files to the server, facebook canvas doesn't show any css at all. i replaced the css filename with the previous one, and it works. why is this?
Actually it looks like facebook is currently experiencing some weird problems with styling. It doesn't cache any new styles, only displays what was previously cached (from yesterday). If you provide a new stylesheet url it will not be able to pull it up (like that url doesn't exist).
During normal conditions what others already suggested should work.
Facebook does like to cache things. Persistently. I don't know why the new file wouldn't have worked, by I can recommend 'spoofing' your css filename with a spurious querystring variable, and incrementing it each time you make an update.
eg
href="my_css_file.css?x=1"
Sounds like the browser is caching your CSS file, which is why even Firebug sees the older version.
There are numerous ways you can prevent the browser from caching your CSS file during development (once in production mode, you probably want it to remain in the cache). The most common technique used by web frameworks like Ruby on Rails is to append a random query string to the URL, like so:
<link rel="stylesheet" type="text/css" href="style.css?96234987" />
...but the trick is that it should be different every time, so the browser thinks it's a different file.
Here are links to a simple trick for PHP, a JSP example, and other possible methods.
According to Include files on facebook developer wiki:
Stylesheet includes are cached automatically by Facebook. Just include a tag like:
<link rel="stylesheet" type="text/css" media="screen"
href="http://yourapp.com/stylesheets/style.css?v=1.0" />
Increment the version number upon each change to your style sheet, as specified above.

Resources