Simple and efficient JavaScript and CSS minification for ASP.NET MVC

NOTE: This project has been discontinued, use ASP.NET bundles instead.

CacheTag helps speed up your page load times in a number of ways:

• Reduces the number of HTTP requests by combining resources
• Makes resources quicker to download thanks to minification
• All resources are hashed, preventing clients from using old resources
• Since any change creates a new hash, resources can be cached aggressively

CacheTag provides a number of benefits compared to other similar frameworks.

• It's real easy to use, see the examples below
• It's flexible because it works with generic lists, no custom bundle classes
• It's faster because it only compiles resources when needed, even in debug mode
• Built to be extendable, use the source Luke!

Add project references to CacheTag.Core and the modules you need, CacheTag.Mvc is a required module for now.

Try something like this in a view:

:::csharp
@Html.RenderStyles(new []
{
	"~/CSS/Reset.css",
	"~/CSS/Site.less"
})
@Html.RenderScripts(new []
{
	"~/Scripts/jquery-1.7.1.js",
	"~/Scripts/app.coffee"
})

You can also reference scripts or styles mid page like this:

@Html.ReferenceScript("~/Scripts/flot.js")

And then render all referenced scripts at once at the end of the page:

@Html.RenderReferencedScripts()

If you want, you can render scripts or styles inline as well, just add Inline to any render method.

Or you can build your scripts and styles manually:

:::csharp
var styleTags = new StyleList(new [] { "~/CSS/Reset.css", "~/CSS/Site.less" }).Compile().RenderHtml();
var scriptTags = new ScriptList(new [] { "~/Scripts/jquery-1.8.0.js", "~/Scripts/app.coffee" }).Compile().RenderHtml();

ScriptList and StyleList are just there for convenience, they only inherit from List<IScriptList> and List<IStyleList> respectively and do a bit of magic to resolve the type of resources based on the file name.

Since we are working with lists, it's easy to do what you want with it.

:::csharp
var scriptUrls =
	new [] {
		new ScriptFile("~/Scripts/jquery-1.8.0.js"),
		new CoffeeScript("~/Scripts/app.coffee")
	}.Compile().Select(x => x.Url);

The code snippet above will load two scripts, compile them if in release mode, and return a list of their resulting URLs. This might be useful for lazy loading scripts via yepnope or something similar.

In release mode resources are combined, and minified if a minification module is referenced, to reduce the number of HTTP requests the client has to make.

<link rel="stylesheet" type="text/css" href="/_cachetag/e4dddf2cdd91d693e023cdc5dc0b56d8664766db.css" />
<script src="/_cachetag/80e9e6fc43c6644ea9badec99eb5c6cbec87c4b0.js" type="text/javascript"></script>

When Web.config is configured for debug mode, resources ar linked individually with a SHA1-hash to ease debugging and prevent any browser cache issues.

:::html
<link rel="stylesheet" type="text/css" href="/CSS/Reset.css" />
<link rel="stylesheet" type="text/css" href="/CSS/Site.less" />
<script src="/Scripts/jquery-1.8.0.js" type="text/javascript"></script>
<script src="/Scripts/app.coffee" type="text/javascript"></script>

Note: To serve .less and .coffee-files individually in debug mode, you need to add their respective HTTP handlers manually (or via NuGet) to your web project.

To use a module, simply make a project reference, it will be configured automatically.

CacheTag.Mvc
Registers routes and an MVC controller for serving scripts

CacheTag.Modules.AjaxMin
Minifies scripts and stylesheets using AjaxMin, depends on AjaxMin

CacheTag.Modules.DotLess
Support for .less style sheets files, depends on dotless.Core

CacheTag.Modules.SassAndCoffee
Provides support for .coffee-scripts for now, depends on SassAndCoffee.Core and SassAndCoffee.JavaScript

The idea is sane defaults and zero configuration, but there are some things you can configure if you want.

CacheTagSettings.HashAlgorithm
MD5 is used by default

CacheTagSettings.RuntimeMode
Default mode is Dynamic, other options are ForceDebug or ForceRelease

CacheTagSettings.HashFilesInDebugMode
If true, then CacheTag will append hash of files includeded in debug mode to force browsers to reload changed resources. Default is off because this confuses debuggers

CacheTagSettings.HideFileExtensions
Set to true if you think file extensions are unnecessary

CacheTagMvcSettings.RouteUrl
Default value is "_cachetag/{id}"

Implement ICacheTagModule and it will automatically be run on startup.

:::csharp
public class ModuleConfiguration : ICacheTagModule
{
	public void Initialize()
	{
		CacheTag.Core.Configuration.Settings.RuntimeMode = RuntimeMode.ForceRelease;
	}
}

Most of CacheTag is based around a couple of extension methods operating on either IEnumerable<IScriptResource> or IEnumerable<IStyleResource>, these are explained here.

Compile()
When operating in debug mode, Compile() does nothing, it just returns the same list it was passed. When in release mode however, it will compile the list of resources using whatever resource compiler is registered for that type of resource. For instance, when using the AjaxMin module, Compile() will minify the list and return a list of one item.

In release mode Compile() also calls Store(), see below.

RenderHtml()
Renders HTML script tags with items linked as external resources.

RenderHtmlInline()
Renders HTML script tags with the resource content inlined.

RenderMvcHtml()
Calls RenderHtml() but wraps the result in a IHtmlString.

RenderMvcHtmlInline()
Calls RenderHtmlInline() but wraps the result in a IHtmlString.

Store()
When serving items as external resources they have to be stored somewhere so they can be retrieved when the browser next requests them. Therefore Store() saves the list of resources in a static Dictionary<> in the class ResourceStorage.

When running a site in production, scripts and styles tend to be static, so storing your compiled resources in a static dictionary should not be a problem.