Edit : I don't know if it actually loads from cache, so I can't create the question named "prevent from loading cache".
Problem : Browsers sometimes save my code and keep loading only the code they saved(Maybe it saves in the cache). When this problem occurs, browser is like caching the old code and won't change anything. This is to say, It won't load any new code I updated.
Information: This occurs in HTML, CSS, Javascript on all browsers. I am using Apache in XAMPP as an appserv.
Deleting cache in all browsers won't fix this.
My first way to stop this is to delete the file, refresh browser and replace it.
The second ways is changing the pathname.
After the fix, the problem will occur again at anytime :(, so I would like to know how to prevent this.
Edited: If possible, please explain for newbie because I am very young beginner.
Try adding a variable like current timestamp to each url in its query string.
Just use querystring e.g. http://www.domain.com/style.css?version=1 for first version.
Now you update the stylesheet and you would like to reflact changes to all users browser who have cached version of old stylesheet. for this just change version querystring value to 1.1
e.g. http://www.domain.com/style.css?version=1.1
This works for javascript, css and all other files called in by your html page.
Also for all files like html, css, js, you can eTag header. More information can be found here.
http://www.w3.org/2005/MWI/BPWG/techs/CachingWithETag.html
I have this weird problem with one of our file. It's named Setup.php and stored under protected/components/
This file is mainly for emails, header, footer generating functions etc. We found out few days back that when we changed the footer layout in this file, the old footer would still show, despite doing a lot of debugging and edits (even removing the footer function itself), it still shows the old one. This is a shocker. I'm aware of cache issues but does Yii cache the whole PHP file? Is this even possible? We are positive the footer used the same function from the same file.
I'm again having this issue with another function in the same file. Determined it's a problem with the component file and Yii, I would like to seek assistance from the Yii users.
Please let me know your thoughts. Thanks in advance.
It's very important for the website I'm working on to be offline-functional. I'm using a Cache Manifest to store all the files on the application cache, so that takes care of that and all is good and well.
BUT, as I read and noticed myself, the browser first shows the cached version of the site before checking for an update online. Hitting refresh reloads the cache again, with the new cached files this time (or what it had time to update for the swift refreshers).
I'm aware of this fix : http://www.html5rocks.com/en/tutorials/appcache/beginner/, where the user is told an update is available and is asked to refresh the page. Not a bad method, but still sketchy for user experience.
Is there any other way to force the browser to show the most up to date files if online? Would cache busting all files manually AND using a cache manifest fix this problem, or will it conflict with the cache manifest and cause problem to the offline functionality?
I found something that works well for me:
The URL linking to the web page contains a parameter. If there is ever a change to the page or related files, the url is changed to something like this: http:/ /www.mywebsite.com/mypage.html?v=3 where v=3 is changed depending on updates.
This is a longer fix to implement (finding every page affected by a change & changing all their cache busting links), but the pages at least show what they're supposed to on the first load and the cache manifest still load the update for offline viewing.
I believe Smarty templates has functionality built in that allows you to manage your site URLs from a config file so if something gets moved, you only have to update the URL in one place. Does this sort of functionality exist in CodeIgniter? If not, any pointers or examples on how/where to add it?
For example:
Instead of hard-coding the link it would be: Settings
But where would you want to set $links so that it was available everywhere? Or is it really best to just hard code them?
Take a look at the config class. It allows you to make custom config files.
It's not entirely made for URL's but you sure can use them.
The base url should be basically right at the start of /app/config/config.php, where app is the name of your codeigniter application folder. You access it through calls to the base_url() function.
Yes, it's called Routes, configuration located at config/routes.php. Documentation
If you ask about the rendered html of the links, then your best bet would be using site_url() in conjunction with constants, for example site_url(URL_SETTINGS);, there is no built in functionality for that, but I can say I don't think that is necessary as it would be used too rarely, but it would influence performance every single load.
I need to clear the IIS cache on my server. The exact reason is detailed below; but the reason doesn't matter. I'm 100% sure that this is the solution I need; as detailed below, I have used the process of elimination to determine that this is, indeed, the problem I'm facing, and the solution I need.
I have an MVC3 app that's themeable (skinnable architecture). Think of it as Wordpress; users can develop a theme, download it, and activate it on their site. The theme controls exactly the final HTML output. This is an over-simplification, since I provide an API with useful functions to be consumed by themes.
Anyway, users can change the theme of the site. The theme is currently stored in a static variable. When a view page is rendered, the name of the theme determines the location of the layout file (which contains references to the CSS files, etc.) and the view files. The theme is a setting that persists in the DB.
For example, if I have a theme called "Foo", then when requesting the /Admin page, I might use /Themes/Foo/Admin.cshtml. If I have another theme called "Bar" which does not have that file, then for /Admin it might request /Themes/Bar/Generic.cshtml as the layout.
The problem is that changing a theme means that every single page on the site is outdated. This means that any sites cached on IIS7 will show the old theme; this is incorrect. I need them to show the new theme.
Anyway, IIS7 uses caching by default. I need essentially a way to clear the cache when a user changes the theme. Currently, this is not happening, and users continue to see the old theme until the cache (somehow) expires itself.
I am not using output caching, or any other form of explicit caching; this is a "vanilla" ASP.NET MVC3 application from a caching perspective (i.e. I didn't add/configure any caching). IIS7 has its own default caching. I know this, because if I disable output caching in IIS7 for my Site, I will always see the correct theme after a change.
How can I flush the cache? Other SO questions point to using Cache.blah, and I tried using HttpContext.Current but that is null during tests (using VS test tool) -- because the ASP.NET pipeline is not used in full.
To explain, in an integration test, I basically:
Go to localhost/Test/
Log in (submit values into the forms)
Change the theme by browsing to the right page and clicking the right link
Request another page
See if the theme changed (based on the layout/css file name).
This is all done by code; I use a C# port of HtmlUnit, and along with deploying my app to /Test in IIS, I can essentially browse it like an end user.
Currently, this test passes around 50% of the time. The problem is that IIS is caching the results, and I can't cleanly reliably reset the cache on the server-side.
Again, I'm not talking about clearing the session or the user-side cache; IIS itself is the culprit guilty of caching my application. Nor do I want to completely disable the cache via the IIS settings, a) because I can't force people who install my application to do that, and b) because caching is good.
So how can I force flushing the cache on the server?
For example, I tried programatically touching web.config; this works, but recycles my application pool, and so, kills my static variables; every request means reloading all the static vars from the DB, which kills my performance.
As you requested I have amended this post:
You can use output cache, you say that the selected theme is stored in the database ( like settings for the site ) Well I would add another column with say a GUID and then use this as the varybycustom value.
Your global.asax file will be able to run code:
void Page_Init() {
///code here to get the GUIDforthissitestheme
var outputCacheSettings = new OutputCacheParameters() {
Duration = Int32.MaxValue, //think its maxvalue
VaryByCustom = GUIDforthissitestheme
};
InitOutputCache(outputCacheSettings);
}
At least here you will have output cache, but also every change of theme, changes the GUID so therefore changes the cache and then your page should be new.
I did something like this on a site that listed products, and when the products database was updated the key would be changed, however I can't find what site I implemented it and I work on a hell of a lot of sites.
hope this helps
Set up 'Cache Rule' in 'Output caching' feature with 'File Cache Monitoring' set to 'Using file change notification'. Then 'touch' the files theme change affects, from .net code you could do:
System.IO.File.SetLastWriteTimeUtc(fileName, DateTime.UtcNow);
The issues you are describing sound a lot like a client side caching issue. Have you checked this with a HTTP Proxy like Fiddler to verify if this is getting cached on the client?
If you are seeing HTTP 304's after a template change you may want to try configuring IIS (or your site template) to disable client side caching.
I dont think the approach mentioned for themes is correct.
If we are using STATIC variables , then it will affect all the users and all the pages.(Which is certainly not required.)
We can think of two approaches,
Use theme name in url and make it as a prat if RouteData. So the url "http://myHost/BLUE/.." will return in BLUE theme and "http://myHost/RED/.." will return in RED theme. If user will change theme then url will be updated.
The problem with above approach is next time user browse, it will load default theme.
So better approach will be save theme as a part of user preference. Once user logged in read the theme from DB and set the RouteData value.
Just touch web.config. That's the easiest and most reliable way. Flushing the application pool programmatically is overkill.
If you have a problem finding out where web.config is in a test environment (since System.Web.HttpRequest.Current is null, and similar for Server), you can always use an app.config file to point out the location.
Again, there's no other easy way to do it; even disabling output caching, as mentioned in the question, is hard to do through web.config alone.