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I am new in web deploying. Now I have to manage windows server and every month I need to deploy new version of applications.
I have trouble with javascript. In almost every version of web applications is changed some javascript file (all javascript files are bundled in one minify javascript file).
Most of users use google chrome. Trouble is browser cacheds styles a javascript files. After deploy new version is loaded in browser old version of javascript file.
Does exists any solution how to resolve this problem programmatically in application or some solution after deploy? In best case withou user colaboration (for example refresh cache by CTRL+R)? What is the best practice?
Our application is developed as .NET CORE 2 Razor Pages web application.
Thanks for advice

Use the tag helpers for script and style files, which take an additional attribute append-version, which appends a new query string value each time there are changes in the files.
<link href="/styles/site.css" append-version="true" />
<script src="/scripts/site.js" append-version="true"></script>

If you are using normal html, css, js project then you can add versioning in your js and css libraries and update your index.html with updated version.
Or if you are using node js, react js, angular js then you can use index.ejs instead of index.html and you can add hash code with your js and css libraries like
script1.1ebecec8538d52c8f844.js
script2.2e765bd6680f0c925e8a.js
style1.1ebecec8538d52c8f844.css
style2.2e765bd6680f0c925e8a.css
Or you can also use CI/CD for npm project.

you can make sure that any updates you’ve made to your bundle files will take place immediately for all users with using versioned names like:
<link rel="stylesheet" href="style.css?v=1.1">
The browser will view a file name of style.css as different from a file name of style.css?v=1.1. It also works for script files as well:
<script src="main.bundle.js?version=1.0.1"></script>
But then If you have one giant file, and change one line of code, the user must download that entire file again. Think of a solution, to creating more smaller files, like with splitting out npm packages used in your solution from your own code, to have better release-flow.

If this is about .css and .js changes, one way is to to "cache busting" is by appending something like "_versionNo" to the file name for each release. For example:
script_1.0.css // This is the URL for release 1.0
script_1.1.css // This is the URL for release 1.1
script_1.2.css // etc.
Or alternatively do it after the file name:
script.css?v=1.0 // This is the URL for release 1.0
script.css?v=1.1 // This is the URL for release 1.1
script.css?v=1.2 // etc.
Please check link
Link

How to reference javascript which is in the parent folder?

I have a web applictaion which use has the following folder structure
application_root
js
in the html, I refer the js like
<script src="../js/****"></script>
everything is file if I start the html page using file:///protocol, but when I use the web server, like http://loclahost:6000/application_root, I found the js cannot be loaded correctly.
How to solve this issue?

You need to start your path with /: <script src="/js/some.js"></script>
Anyway, this can be problematic because if you use a virtual directory, / won't work since it's the root path.
For example: /js/some.js is http://localhost/js/some.js, and if your web site is hosted in a virtual directory like http://localhost/myapp/js/some.js this approach won't work.
If you find above case part of your issue, you might need to use server-side code to get your application root (i.e. /myapp/) so you can concatenate /myapp/ to js/some.js and get the right URI.

how to load the latest javascript files every time the user visits the website [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How do I force the refresh of javascript files in a browser?
My application in ASP.NET MVC based and javascript files are included in .csHtml file.
I require this so that the user do not have to do a [Ctrl+F5] or manually clear cache and the most recent version of javascript file is loaded everytime in the browser.
I appreciate if some examples can be provided.
Primary technique suggested is to use a dummy paramater while including the file.
Also I do not what to change the parameter manually every time I modify a js file. Need some examples if this can be done automatically.
EDIT 1:
Please provide solution to this with ASP.NET MVC prospective.

Put a version number in the filename for your JS files (like jQuery does). Then, whenever you rev the JS files, you bump the version and change the HTML files that include it.
The jQuery file naming example:
jquery-1.8.3.js
jquery-1.9.0.js
This lets you set very long caching on your server for the JS files themselves which really helps with performance on your site. But, any time you rev the JS files, the viewer gets the new JS files immediately because the newly named files are pulled by the new HTML file because they aren't in the browser cache.

You want to use Bundling and Minification. Depending on your version of MVC, the implementation is slightly different. In the newest version, it is used by default.
Bundling and Minification will combine and minify all your scripts (and styles sheets) into one file (or multiple, depending on how you use it) and serve them up with a unique parameter. Any time a file changes in that particular bundle (and thus the user would require to download the new files) the parameter automatically changes.
For MVC3, you'll need to install Microsoft Web Optimization.
Then in your global.ascx, you'd do something like this and call it from Application_Start:
private static void SetupBundling()
{
var jsBundle = new Bundle("~/Scripts/js", typeof(JsMinify));
jsBundle.AddDirectory("~/Scripts/", "*.js", false);
jsBundle.AddDirectory("~/Scripts/anothr-good-folder/", "*.js", false);
BundleTable.Bundles.Add(jsBundle);
var randomBundle = new Bundle("~/Scripts/random", typeof(JsMinify));
randomBundle.AddFile("~/Scripts/random/main.js");
randomBundle.AddFile("~/Scripts/random/cool.js");
BundleTable.Bundles.Add(randomBundle);
var cssBundle = new Bundle("~/Content/css", typeof(CssMinify));
cssBundle.AddDirectory("~/Content/", "*.css", false);
BundleTable.Bundles.Add(cssBundle);
}
So that first bundle will bundle every .js file in your ~/Scripts folder. In your head file you can reference it like:
<script src="#Microsoft.Web.Optimization.BundleTable.Bundles.ResolveBundleUrl("~/Scripts/js")" type="text/javascript"></script>
And it will be rendered like:
<script src="/Scripts/js?v=-2573834892993289" type="text/javascript"></script>
And any time one of your .js files change (or .css), so will the parameter.
Similar implementation for the CSS bundle, and also if you want to reference the randomBundle only on certain pages.

You can do cache-busting by attaching a random hash or number URL parameter after each javascript file URL like so:
http://www.bestsiteonearth.yes/cool_javascript.js?cache_buster=2187sasas1289012890aohkjaiosa0990
Since that number is different each time the page is loaded the URL will not be cached. More info here. Tutorial gives PHP examples, but if you know how to create a hash or random number in any language & can attach it to a URL you are good to go.

Personally I use PHP, but the way I do this is to search the output buffer for static files, such as images, scripts and stylesheets (and audio, video, whatever), then retrieve their modification time from the filesystem and append it as /t=TIMESTAMP. I then use .htaccess to strip the timestamp off and get the original filename. This is preferred over query strings because many clients will not cache files with query strings, and it's also preferred over versioning because it updates automatically simply by modifying the file.

Forcing the browser to reload css/js only if they have changed

There are a lot of questions and answers on SO related to my problem [I want the browser to cache js/css forever. During a new release if some of the js/css files have been updated, the browser should reload and cache them.]
This solution seemed most appropriate to me :
What is an elegant way to force browsers to reload cached CSS/JS files?
However, there is just one thing that I am unable to figure out.
The solution makes use of last_modified_time. However, I am not allowed to use it. I need to use some other mechanism.
What are the options? Is there a possibility of pre-calculating the versions during build and updating(replacing) them in jsps via build script (before deployment, so that the version numbers are not calculated on run time)? Any existing tool for this purpose? I use Java/Jsp.

We always use
file.css?[deploytimestamp]
This way the CSS file is cached for each deployment at the client. The same goes for our minified javascript. Is this an option for you?

It may not be the best way, but this is what I am doing now:
All of my js/css have a [source control = svn] revision number
References in my jsp are like /foo/path1/path2/xyz000000/foo.
Build Step 1 - Generate a map of css|js files and their revision numbers
Build Step 2 - Replace xyz000000 references in jsps with a hash of svn revisions
A rule in url rewriter to direct all /foo/path1/path2/xyz<767678>/foo. to /foo/path1/path2/foo.[js|css]
Infinitely cache the css|js files
Whenever there is a commit, the revision number changes and so do the references in .jsp

Generate an md5-hash of each css file after deployment. Use this hash instead of the timestamp in the url of the css.
file.css?[hash of file.css contents]
It may be wise to calculate the hashes once after deployment and store them to gain some performance. You could store them in a database, or even in a PHP array in a separate file that is included in your website code.

LESS (dynamic style sheet language) and Resource Loaders

I am currently looking at changing from using css to LESS in my current project. A few things to mention before I get to the question are:
1) The project is purely clientside (Html/Js/Css) so there is no server side component for the website (although there is a web service it calls via CORS)
2) I load almost everything via resource loading frameworks, currently I am using yepnope
So given the above I need to be able to get the LESS styles to be processed clientside, but as I am using a resource loader and more css/less could be loaded after the initial page load has happened I was wondering if:
1) Does Less work with content loaders when using client side processing? As it says:
Client-side usage
Link your .less stylesheets with the rel set to “stylesheet/less”:
<link rel="stylesheet/less" type="text/css" href="styles.less">
Then download less.js from the top of the page, and include it in the <head> element of your page, like so:
<script src="less.js" type="text/javascript"></script>
Make sure you include your stylesheets before the script.
I think I may be able to tell yepnope how to handle less files and give them the required element attributes. If I can providing the less resources are brought in before the less javascript will it be ok?
2) Is there any manual way to tell it what to process in javascript?
This would cover the case where everything has been loaded for the current page, the user clicks a button which dynamically loads a new template which is displayed in the current page, this may require new less resources to be loaded, but the less.js file has already been included.
Hopefully the above gives you some context as to what I am trying to do and what the 2 questions are.

Yes you can.
Reading this post Load less.js rules dynamically and adjusting it a bit:
less.sheets.push(document.getElementById('new-style-1'));
// Add the new less file to the head of your document
var newLessStylesheet = $("<link />").attr("id", "new-style-1").attr("href", "/stylesheets/style.less").attr("type", 'text/less');
$("head").append(newLessStylesheet);
// Have less refresh the stylesheets
less.refresh(true);
You could also generate all the CSS in your development environment and put it in one file.
There are lots of options. The easiests way would be to use an application. You could use apps like http://incident57.com/less/ for Mac. You can even compile online: Search for something as "lessphp".