How do I clear a browsers cache with JavaScript?
We deployed the latest JavaScript code but we are unable to get the latest JavaScript code.
Editorial Note: This question is semi-duplicated in the following places, and the answer in the first of the following questions is probably the best. This accepted answer is no longer the ideal solution.
How to force browser to reload cached CSS/JS files?
How can I force clients to refresh JavaScript files?
Dynamically reload local Javascript source / json data
Update: See location.reload() has no parameter for background on this nonstandard parameter and how Firefox is likely the only modern browser with support.
You can call window.location.reload(true) to reload the current page. It will ignore any cached items and retrieve new copies of the page, css, images, JavaScript, etc from the server. This doesn't clear the whole cache, but has the effect of clearing the cache for the page you are on.
However, your best strategy is to version the path or filename as mentioned in various other answers. In addition, see Revving Filenames: don’t use querystring for reasons not to use ?v=n as your versioning scheme.
You can't clear the cache with javascript.
A common way is to append the revision number or last updated timestamp to the file, like this:
myscript.123.js
or
myscript.js?updated=1234567890
Try changing the JavaScript file's src? From this:
<script language="JavaScript" src="js/myscript.js"></script>
To this:
<script language="JavaScript" src="js/myscript.js?n=1"></script>
This method should force your browser to load a new copy of the JS file.
Other than caching every hour, or every week, you may cache according to file data.
Example (in PHP):
<script src="js/my_script.js?v=<?=md5_file('js/my_script.js')?>"></script>
or even use file modification time:
<script src="js/my_script.js?v=<?=filemtime('js/my_script.js')?>"></script>
You can also force the code to be reloaded every hour, like this, in PHP :
<?php
echo '<script language="JavaScript" src="js/myscript.js?token='.date('YmdH').'">';
?>
or
<script type="text/javascript" src="js/myscript.js?v=<?php echo date('YmdHis'); ?>"></script>
window.location.reload(true) seems to have been deprecated by the HTML5 standard. One way to do this without using query strings is to use the Clear-Site-Data header, which seems to being standardized.
put this at the end of your template :
var scripts = document.getElementsByTagName('script');
var torefreshs = ['myscript.js', 'myscript2.js'] ; // list of js to be refresh
var key = 1; // change this key every time you want force a refresh
for(var i=0;i<scripts.length;i++){
for(var j=0;j<torefreshs.length;j++){
if(scripts[i].src && (scripts[i].src.indexOf(torefreshs[j]) > -1)){
new_src = scripts[i].src.replace(torefreshs[j],torefreshs[j] + 'k=' + key );
scripts[i].src = new_src; // change src in order to refresh js
}
}
}
try using this
<script language="JavaScript" src="js/myscript.js"></script>
To this:
<script language="JavaScript" src="js/myscript.js?n=1"></script>
Here's a snippet of what I'm using for my latest project.
From the controller:
if ( IS_DEV ) {
$this->view->cacheBust = microtime(true);
} else {
$this->view->cacheBust = file_exists($versionFile)
// The version file exists, encode it
? urlencode( file_get_contents($versionFile) )
// Use today's year and week number to still have caching and busting
: date("YW");
}
From the view:
<script type="text/javascript" src="/javascript/somefile.js?v=<?= $this->cacheBust; ?>"></script>
<link rel="stylesheet" type="text/css" href="/css/layout.css?v=<?= $this->cacheBust; ?>">
Our publishing process generates a file with the revision number of the current build. This works by URL encoding that file and using that as a cache buster. As a fail-over, if that file doesn't exist, the year and week number are used so that caching still works, and it will be refreshed at least once a week.
Also, this provides cache busting for every page load while in the development environment so that developers don't have to worry with clearing the cache for any resources (javascript, css, ajax calls, etc).
or you can just read js file by server with file_get_contets and then put in echo in the header the js contents
Maybe "clearing cache" is not as easy as it should be. Instead of clearing cache on my browsers, I realized that "touching" the file will actually change the date of the source file cached on the server (Tested on Edge, Chrome and Firefox) and most browsers will automatically download the most current fresh copy of whats on your server (code, graphics any multimedia too). I suggest you just copy the most current scripts on the server and "do the touch thing" solution before your program runs, so it will change the date of all your problem files to a most current date and time, then it downloads a fresh copy to your browser:
<?php
touch('/www/control/file1.js');
touch('/www/control/file2.js');
touch('/www/control/file2.js');
?>
...the rest of your program...
It took me some time to resolve this issue (as many browsers act differently to different commands, but they all check time of files and compare to your downloaded copy in your browser, if different date and time, will do the refresh), If you can't go the supposed right way, there is always another usable and better solution to it. Best Regards and happy camping.
I had some troubles with the code suggested by yboussard. The inner j loop didn't work. Here is the modified code that I use with success.
function reloadScripts(toRefreshList/* list of js to be refresh */, key /* change this key every time you want force a refresh */) {
var scripts = document.getElementsByTagName('script');
for(var i = 0; i < scripts.length; i++) {
var aScript = scripts[i];
for(var j = 0; j < toRefreshList.length; j++) {
var toRefresh = toRefreshList[j];
if(aScript.src && (aScript.src.indexOf(toRefresh) > -1)) {
new_src = aScript.src.replace(toRefresh, toRefresh + '?k=' + key);
// console.log('Force refresh on cached script files. From: ' + aScript.src + ' to ' + new_src)
aScript.src = new_src;
}
}
}
}
If you are using php can do:
<script src="js/myscript.js?rev=<?php echo time();?>"
type="text/javascript"></script>
Please do not give incorrect information.
Cache api is a diferent type of cache from http cache
HTTP cache is fired when the server sends the correct headers, you can't access with javasvipt.
Cache api in the other hand is fired when you want, it is usefull when working with service worker so you can intersect request and answer it from this type of cache
see:ilustration 1 ilustration 2 course
You could use these techiques to have always a fresh content on your users:
Use location.reload(true) this does not work for me, so I wouldn't recomend it.
Use Cache api in order to save into the cache and intersect the
request with service worker, be carefull with this one because
if the server has sent the cache headers for the files you want
to refresh, the browser will answer from the HTTP cache first, and if it does not find it, then it will go to the network, so you could end up with and old file
Change the url from you stactics files, my recomendation is you should name it with the change of your files content, I use md5 and then convert it to string and url friendly, and the md5 will change with the content of the file, there you can freely send HTTP cache headers long enough
I would recomend the third one see
You can also disable browser caching with meta HTML tags just put html tags in the head section to avoid the web page to be cached while you are coding/testing and when you are done you can remove the meta tags.
(in the head section)
<meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
<meta http-equiv="Pragma" content="no-cache" />
<meta http-equiv="Expires" content="0"/>
Refresh your page after pasting this in the head and should refresh the new javascript code too.
This link will give you other options if you need them
http://cristian.sulea.net/blog/disable-browser-caching-with-meta-html-tags/
or you can just create a button like so
<button type="button" onclick="location.reload(true)">Refresh</button>
it refreshes and avoid caching but it will be there on your page till you finish testing, then you can take it off. Fist option is best I thing.
I tend to version my framework then apply the version number to script and style paths
<cfset fw.version = '001' />
<script src="/scripts/#fw.version#/foo.js"/>
Cache.delete() can be used for new chrome, firefox and opera.
I found a solution to this problem recently. In my case, I was trying to update an html element using javascript; I had been using XHR to update text based on data retrieved from a GET request. Although the XHR request happened frequently, the cached HTML data remained frustratingly the same.
Recently, I discovered a cache busting method in the fetch api. The fetch api replaces XHR, and it is super simple to use. Here's an example:
async function updateHTMLElement(t) {
let res = await fetch(url, {cache: "no-store"});
if(res.ok){
let myTxt = await res.text();
document.getElementById('myElement').innerHTML = myTxt;
}
}
Notice that {cache: "no-store"} argument? This causes the browser to bust the cache for that element, so that new data gets loaded properly. My goodness, this was a godsend for me. I hope this is helpful for you, too.
Tangentially, to bust the cache for an image that gets updated on the server side, but keeps the same src attribute, the simplest and oldest method is to simply use Date.now(), and append that number as a url variable to the src attribute for that image. This works reliably for images, but not for HTML elements. But between these two techniques, you can update any info you need to now :-)
Most of the right answers are already mentioned in this topic. However I want to add link to the one article which is the best one I was able to read.
https://www.fastly.com/blog/clearing-cache-browser
As far as I can see the most suitable solution is:
POST in an iframe. Next is a small subtract from the suggested post:
=============
const ifr = document.createElement('iframe');
ifr.name = ifr.id = 'ifr_'+Date.now();
document.body.appendChild(ifr);
const form = document.createElement('form');
form.method = "POST";
form.target = ifr.name;
form.action = ‘/thing/stuck/in/cache’;
document.body.appendChild(form);
form.submit();
There’s a few obvious side effects: this will create a browser history entry, and is subject to the same issues of non-caching of the response. But it escapes the preflight requirements that exist for fetch, and since it’s a navigation, browsers that split caches will be clearing the right one.
This one almost nails it. Firefox will hold on to the stuck object for cross-origin resources but only for subsequent fetches. Every browser will invalidate the navigation cache for the object, both for same and cross origin resources.
==============================
We tried many things but that one works pretty well. The only issue is there you need to be able to bring this script somehow to end user page so you are able to reset cache. We were lucky in our particular case.
window.parent.caches.delete("call")
close and open the browser after executing the code in console.
Cause browser cache same link, you should add a random number end of the url.
new Date().getTime() generate a different number.
Just add new Date().getTime() end of link as like
call
'https://stackoverflow.com/questions.php?' + new Date().getTime()
Output: https://stackoverflow.com/questions.php?1571737901173
I've solved this issue by using
ETag
Etags are similar to fingerprints, and if the resource at a given URL changes, a new Etag value must be generated. A comparison of them can determine whether two representations of a resource are the same.
Ref: https://developer.mozilla.org/en-US/docs/Web/API/Cache/delete
Cache.delete()
Method
Syntax:
cache.delete(request, {options}).then(function(found) {
// your cache entry has been deleted if found
});
In our app, we are serving static angular app files out of foobar.com/public/angular. The home page (foobar.com) is configured to serve foobar.com/public/angular/index.html. Thus, in our index file's <head>, we have:
<base href="http://foobar.com/public/angular">
However, during development, we use foobar.com/debug, which causes the server to use this instead:
<base href="http://foobar.com/public/angular-debug">
The server returns unprocessed (not minified, uglified, etc) versions of the files from this url. We are also using angular-route for our views.
TLDR:
We have a production route: foobar.com
We have a dev route: foobar.com/debug
We have a base tag: <base href="http://foobar.com/public/whatever">
We are using hash-bang urls for angular routes
The trouble is generating urls on the client side. As discussed in comments, Click here does not work because the resulting url contains the base tag, which the server rejects and looks odd since the user starts somewhere else: foobar.com/public/angular/#/myRoute). The best I could think of to create the desired url was this:
/**
* Returns current url after replacing everything after the hashbang with a new string.
*
* #param {string} s - string to change route with (e.g. 'asdf')
* #return {string} - new url e.g. http://google.com/foobar/#!/asdf
*/
makeRouteUrl = function(s) {
var root = $location.absUrl().match(/.*#!/);
if (root && (root.length > 0)) {
root = root[0];
return( root + s );
} else {
// no hashbang in path? Choose home page (not intended use)
return "/";
}
}
However, this just seems a little gross. Is there a function in angular that makes the above function unnecessary? I have looked for functions in $location, $route, etc., but nothing seems to handle our complex setup correctly. We need to ultimately get the url as a string, not navigate (we are supporting open in new tab, so need to used ng-href). Since Angular apps often use hashbang urls for routing, I figured there must be something that allows you the just change the route after the hashbang while still preserving what's in front of it.
I'm not entirely sure if I understand the problem...
$location.url('/stuff/after/hash?params=hey');
Or if you only want to set the path after #:
$location.path('/stuff/after/hash');
Is what I usually use. But you need to return the url without hash after this?
How about
window.location.origin + window.location.pathname
For the current url without hashes and parameters?
Have you considered using the UI Router library?
In general, it's excellent.
Specific to your question, the UrlMatcher service provides a method format that- unless I'm misunderstanding what you're asking- does what you're trying to do.
new UrlMatcher('/your/route/here').format(optionalNamedParameters);
// returns a formatted URL
I have a very standard ASP MVC app that I use a little javascript to show a Partial View. In order to make that Javascript work I needed to hard code a path to the Partial which is different between Dev and Production.
Mainly, in Dev there is no App specification where as in Production there is. See here:
Production=var URL = '/WetWashRequest/wetWashRequests/GetDetails?WONumber=' + wo;
Dev = var URL = '/wetWashRequests/GetDetails?WONumber=' + wo;
What this means is that as I work on it locally I delete the first part and when I want to deploy I have to remember to re add it.
This seems so ridiculously flawed that I can only assume I am being ignorant and doing something wrong...
You can take advantage of UrlHelper to get the URLs, as long as you do it in view:
var URL = '#Url.Action("GetDetails")';
Obviously, it doesn't make sense to put all your JavaScript in view, so what I will normal do is set just this in my view, in a namespace var, and then reference it in my external JavaScript:
View
<script>
var MyApplication = MyApplication || {};
MyApplication.GetDetailsUrl = '#Url.Action("GetDetails")';
</script>
External JS
$.get(MyApplication.GetDetailsUrl, { WONumber: wo }, function (result) {
...
});
Our site contains href links to various subdomains: foo.mysite.com, bar.mysite.com. For testing purposes, I'd like to run the site on a completely different main domain name, and point to subdomains off the new domain name.
Rather than manually change all the links, I'd like to have only one version of the site with links that look like this:
Link
What's the simplest syntax for doing this?
I know I could write jQuery code to hijack links, but a simpler in-link syntax would be better.
You could try on click:
<a href="foo.{host}/mypage?myparam=value"
onclick="this.href=this.href.replace('{host}', window.location.hostname)">Link</a>
Couldn't you use javascripts onclick event ? tpo do this :
Link
Honestly, the easy way for such a simple, global testing change is to do a search/replace on your whole site. If you want to proceed with your plan, I would use a server side language such as PHP, if possible. It will be much more foolproof for what you want.
I've seen back-end systems use an ENV variable to make changes between production environments. For example, you would set an environment variable, like var ENV = 'live' or var ENV = 'production. You could then use that to define what subdomain to use.
var ENV = 'production';
// set subdomain based on ENV variable
var subdomain = 'bar';
if(ENV == 'production'){
var subdomain = 'foo';
}
// modify every link to use the subdomain
$('a').each(function(){
var modifyHref = 'http://' + subdomain + $(this).attr('href')
$(this).attr('href', modifyHref);
});
I don't think you should be doing this on front-end JS though.
If subdomains are an issue, I would set all the paths to <a href="/mypage?myaparam=value">. That way, it won't matter what the subdomain. If you are on the foo subdomain, it will go to "foo.whatever/mypage?myaparam=value", and if you are on the bar subdomain, it will go to "bar.whatever/mypage?myaparam=value".
I am having some difficulty aligning my paths without a hardcode in javascript. I am running an asp.net MVC3 web application.
If my path is of the form
var url = 'http://serverNameHardcode/websiteNameHardcode/service/service?param1=' + param;
Then things work fine when I do
$.get(url,
{},
function (data) {alert('callback success');},'json');
I would like to create a relative path. I tried
var url = 'service/service?param1=' + param;
And this works when I run locally and also in Firefox, but not in IE7. When I publish to the server without the hardcode the callback never fires. I know MVC-3 adds some complexity to routing, but I do not know if it applies to this situation; so, I marked this question as such.
How should I setup my path so I don't need hardcodes?
Just write out the app path as a global js variable from your master view, then compose links as
APPPATH + "path/whatever"
Just had to solve this for one of my jQuery plugins, where it is preferable not to modify anything global (i.e. outside the scope of the plugin use) so I had to disregard the marked answer.
I also found that because I host DEV locally in IIS I could not use a root-relative path (as localhost is not the root).
The solution I came up with extended what I had already started with: a data-controller attribute specifying which controller to use in the element I am applying my plugin to. I find it preferable to data-drive the controller names so the components can be more easily reused.
Previous:
<div data-controller="Section">
Solution:
<div data-controller="#Url.Content("~/Section")">
This injects the server root (e.g. /Test.WindowsAzure.Apr2014/ before the controller name so I wind up with /Test.WindowsAzure.Apr2014/Section which is perfect for then appending actions and other parameters as you have. It also avoids having an absolute path in the output (which takes up extra bytes for no good reason).
In your case use something like:
// Assuming $element points to the element your plugin/code is attached to...
var baseUrl = $element.data('controller');
var url = baseUrl + '/service?param1=' + param;
Update:
Another approach we now use, when we do not mind injecting a global value, is Razor-inject a single global JavaScript variable onto window in the layout file with:
<script>
window.SiteRoot = "#Url.Content("~/")";
</script>
and use it with
var url = window.SiteRoot + '/service?param1=' + param;
One option:
var editLink = '#Url.Action("_EditActivity", "Home")';
$('#activities').load(editLink + "?activityID=" + id);
another example:
var actionURL = '#Url.Action("_DeleteActivity", "Home")';
$('#activities').load(actionURL + "?goalID=" + gID + "&activityID=" + aID);
If you don't need to add to the string:
$('#activities').load('#Url.Action("_Activities", "Home", new { goalID = Model.goalID},null)');
I really need the path to get this to work, maybe its IE7. Who knows. But this worked for me.
Grab the URL and store it somewhere. I chose to implement the data attribute from HTML5.
<div id="websitePath" data-websitePath='#Request.Url.GetLeftPart(System.UriPartial.Authority)#Request.ApplicationPath'></div>
Then when you need to perform some AJAX or otherwise use a URL in javascript you simply refer to the stored value. Also, there are differences in the versions of IIS (not cool if your devbox is IIS5 and your server is IIS7). #Request.ApplicationPath may or may not come back with a '/' appended to the end. So, as a workaround I also trim the last character if it is /. Then include / as part of the url.
var urlprefix = $('#websitePath').data('websitepath');
urlprefix = urlprefix.replace(/\/$/, "");
var url = urlprefix + '/service/service?param1=' + param;
While the accepted answer is correct I would like to add a suggestion (i.e. how I do it).
I am using MVC, and any ajax request goes to a controller. My controllers have services so if a service call is required the controller will take of that.
So what's my point? So if ajax always communicates with a controller, then i would like to let the MVC routing resolve the path for me. So what I write in Javascript for url is something like this:
url: 'controller/action'
This way there is no need for the root path etc...
Also, you can put this in a separate Javascript file and it will also work whereas #Url.Content will need to be called on the view.