Bundling and minification ASP.NET - asp.net

I have a huge web application that bundles and minifies a huge amount of javascript and css files.
When we release a new version, we notice that at the first request of each page (controller + view) the software takes a lot of time to respond. So, I started to search a little bit and find out Bundle Caching and it seems when some .js or .css files are changed, the bundle will create a new token. But I have some doubts about it:
When exactly the join and minification of the files is made? It is when it is called at the first time on a view?
There is a possibility that when the software is build, the files will be joined and minified during that process, so when at the first time the virtual path is called, this process already had occurred and cached?
If the slowly problem about my application is not the bundling and minification of the files, what could be?
Thank you.
Note: I'm talking about the process in a production environment. So,
thinks like putting debug=false in the web.config I already have.

1) I would not bet on this one, but I am pretty sure that this needs to be done upfront provided that the version of the bundle is appended to the path as a query string parameter. Since this value is the hash of the bundle result, this needs to be done before any bundle can be downloaded in order for ASP.NET to even be able to add this parameter when you do something like this:
#Url.Content("~/bundles/yourbundle")
Whether it is calculated the first time the bundle url is rendered into the view or at app startup is something I don't know. I still post this answer because I believe I can give you useful information for the 2) and 3) points.
2) It is possible to bundle your files beforehand. You can either use some Gulp or Grunt task, use the Bundler & Minifier extension, or any tool of your preference. In that case, however, you are not required (or even advised1) to use virtual paths as these tools produce physical files. However, you will need to make sure yourself that they are versioned properly so whenever you change some input file, the clients will be forced to download the new one instead of using the one in their cache.
3) Keep in mind that C# is not compiled to machine code. Initial slowness can, and usually is, caused by something called JITting (which is explained in greater detail here), that is, the process of transforming the IL code into machine code. This is a rather lazy process in that it basically happens just before the actual execution of your code. If, for example, you have a method A, it does not get transformed to machine code up until it is actually invoked. Therefore, the first access of every controller/action is slower than subsequent ones (because after the first run, the resulting machine code is kept).
You can also configure your project to compile your views which will cause your app to be slightly faster at the cost of making the build process slower.
1 It is advisable to use physical paths if the files are actually physically present on the disk because like that, you can skip the virtual path resolving process altogether thus making script loading to be a little bit faster.

Bundling and minification is enabled or disabled by setting the value of the debug attribute in the compilation Element in the Web.config file. In the following XML, debug is set to true so bundling and minification is disabled.+
XML
<system.web>
<compilation debug="true" />
<!-- Lines removed for clarity. -->
</system.web>
To enable bundling and minification, set the debug value to "false". You can override the Web.config setting with the EnableOptimizations property on the BundleTable class. The following code enables bundling and minification and overrides any setting in the Web.config file.
C#
public static void RegisterBundles(BundleCollection bundles)
{
bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
"~/Scripts/jquery-{version}.js"));
// Code removed for clarity.
BundleTable.EnableOptimizations = true;
}
Unless EnableOptimizations is true or the debug attribute in the compilation Element in the Web.config file is set to false, files will not be bundled or minified. Additionally, the .min version of files will not be used, the full debug versions will be selected. EnableOptimizations overrides the debug attribute in the compilation Element in the Web.config file

Related

ScriptBundle adding both full and minified file in debug mode

I have the following ScriptBundle defined in BundleConfig.cs-
public class BundleConfig
{
public static void RegisterBundles(BundleCollection bundles)
{
bundles.Add(new ScriptBundle("~/js/yepnope").Include(
"~/Scripts/yepnope.{version}.js"));
}
}
It isn't in fact the only bundle, but that is all in there that is pertinent to the question - the rest is just other bundle definitions.
When in "debug" mode as set in the web.config-
<compilation debug="true" targetFramework="4.5">
Both the full and minified versions of the script are sent to the browser-
<script src="/Scripts/yepnope.1.5.4-min.js"></script>
<script src="/Scripts/yepnope.1.5.4.js"></script>
The script is added using the HTML helper like so-
#section HeadScripts
{
#Scripts.Render("~/js/yepnope")
}
This is an MVC4 project running in Visual Studio 2012 on Windows 7 Professional 64-bit.
Whatever I do I cannot get the {version} wildcard to behave as described in the Microsoft documentation-
Note: Unless EnableOptimizations is true or the debug attribute in the
compilation Element in the Web.config file is set to false, files
will not be bundled or minified. Additionally, the .min version of
files will not be used, the full debug versions will be selected.
For ASP.NET MVC 4, this means with a debug configuration, the file
jquery-1.7.1.js will be added to the bundle. In a release
configuration, jquery-1.7.1.min.js will be added. The bundling
framework follows several common conventions such as:
Selecting “.min” file for release when “FileX.min.js” and “FileX.js”
exist.
Selecting the non “.min” version for debug.
Ignoring “-vsdoc”
files (such as jquery-1.7.1-vsdoc.js), which are used only by
IntelliSense.
The {version} wild card matching shown above is used to
automatically create a jQuery bundle with the appropriate version of
jQuery in your Scripts folder. In this example, using a wild card
provides the following benefits:
Allows you to use NuGet to update to a newer jQuery version without
changing the preceding bundling code or jQuery references in your view
pages.
Automatically selects the full version for debug configurations
and the ".min" version for release builds.
If I add "EnableOptimizations" it seems to behave as expected.
Has anyone else noticed this or found a solution?
MVC4 only knows how to handle a .min.js file. It doesn't recognize -min.js (with a dash).
The way I typically do this, with easy success, is to get rid of any .min.js or -min.js files provided by libraries that provide both a .js and either a .min.js or -min.js. By default, MVC will automatically minify any bundled .js files when you deploy your website, so there's no need to use the provided .min.js or -min.js files.
This isn't necessarily a direct answer to your particular question - it's a way to circumvent the problem entirely.

IIS Web application and class-library configuration - config file is lost when deployed

I have an ASP.NET web application written in C# 4.0. The application references a class library that comes with its own configuration file. At runtime, the class library uses similar to the following code to load this specific configuration:
var exeConfigPath = this.GetType().Assembly.Location;
var config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
This is done because the library has to load its bundled configuration rather than the application configuration. The application configuration should not be concerned of the library's settings and should not be able to alter them.
Now, there are a few other things that need to be done for this concept to work. I have to set the library's configuration file build operation as Content in the properties window and the Copy to be Copy Always or Copy If Newer. So far so good - the file gets automatically both into the class library's bin directory, and the web applications's bin directory, and is correctly renamed from App.config to CustomLibrary.dll.config (as supposed, the library's dll is CustomLibrary.dll).
Now I am facing two issues.
1) When I publish the web application to a filesystem location (mapped in IIS), the CustomLibrary.dll.config appears back as App.config in the bin folder of the published app. OK - I will rename it in the class library project to match the expected convention - and problem solved.
2) Even when published, the IIS compiles the application again and stores it in the ASP.NET Temporary Files. There is a fancy directory structure with a folder dedicated for each assembly referenced. The folder corresponding to the CustomLibrary.dll does not contain the config file in it. Since this.GetType().Assembly.Location will return the path to the temp folder, the application fails to load the configuration and crashes as it should.
I need to preserve the pattern of having the configuration in the class library, and be able to make it work in the web application. When manually copying the .config to the temp folder, the app works, but see, I really hate manual copying to randomly-named folders.
Is there a way to either prevent IIS from using the temp folders, or to make it copy along the config files? I believe the problem I am facing is configuration-related rather than conceptual since the application works as expected when the config file is in place. I'd prefer not to mess with using hard-coded physical paths to the config file either.
Edit:
To make it clearer, I will point out what and why I want to achieve. The idea is that the library and the web project will be developed as separate products - there will be no user or application specific information in the configuration of the library, so it will not change for different use scenarios. It is also rather specific to the class library functionality rather than the end application. It makes sense for me to keep the library's configuration information bundled within it (similar to Java, where a spring context xml file, or a properties file, get bundled with the jar of the library). I'd like to avoid having to copy the configuration in each app/web config of the consumer application. There will be cases where the consumer application is developed by third parties, and I do not want to rely on them doing their configuration right for my stuff to work. Again, the only issue here is not having the config file copied to the right place.
If those are static, internal settings that nobody should see or change, wouldn't you be better off having a file with the configuration included within the class library as an embedded resource? Either that or just a static class with the settings.
That way you'd be certain that nobody alters it, which in your scenario seems to be a plus.
I have come along a way to work arround the described issue, still not a very pleasant one to my requirements.
The solution is to take advantage of the application configuration (web.config in web apps, or app.config) which is always available. I have added as settings the absolute paths to the config file for each library. So I ended up with:
<!--
THIS IS IN THE WEB.CONFIG FILE
-->
<appSettings>
<add key ="ClassLibrary_ConfigPath"
value ="{My Publish Output Folder}\ClassLibrary.dll.config"/>
</appSettings>
and the class library now uses the following code to load its configuration:
Configuration config = null;
try
{
var exeConfigPath = this.GetType().Assembly.Location;
config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
}
catch (Exception e)
{
if (!IsConfigurationNotFoundError(e))
{
// IsConfigurationNotFoundError logic skipped for brevity
var exeConfigPath =
ConfigurationManager.AppSettings["ClassLibrary_ConfigPath"];
if (exeConfigPath != null)
{
config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
}
}
else
{
throw;
}
}
While this works, I will wait for a better solution if possible. Still, I do not have to copy the entire ClassLibrary.dll.config into the web.config file, but now I must manage filesystem locations and be aware of app-setting names. What I really want is the consumer app of the ClassLibrary.dll not to deal with its configuration in any way. If it were a desktop app, I have this covered, as Visual Studio copies the ClassLibary.dll.config appropriately. I hope there is a way to make it work smoothly for web apps.
The short answer is: you can't. You have to merge both configuration sections and place all settings in the main configuration file of your application. In case of the web application it would be the web.config. Read this

IIS take long time to first run

I have a big website and we converted it to a web application. then again we published the application and get the result files in to another web application and do our own development on top of that. above steps are taken to reduce the build time. it reduced the build time but take long time to the first run. our site containing large number of files. is there any suggessions to reduce the run time. after each and every change we have to wait 5-10 minutes to load the site.
I think Application Initialization Module will be usefull for you ;)
EDIT
Adding following code solved the problem,
<compilation optimizeCompilations="true" />
Optional Boolean attribute Specifies whether dynamic compilation will
recompile an entire site if a top-level file is changed. Top-level
files include the Global.asax file and all files in the Bin and
App_Code folders. If True, only changed files are recompiled.The
default is False. For more information, see Understanding ASP.NET
Dynamic Compilation.

Assembly unavailable after Web.config change

I'm using a custom framework that uses reflection to do a GetTypeByName(string fullName) on the fully-qualified type name that it gets from the database, to create an instance of said type and add it to the page, resulting in a standard modular kind of thing.
GetTypeByName is a utility function of mine that simply iterates through Thread.GetDomain().GetAssemblies(), then performs an assembly.GetType(fullName) to find the relevant type. Obviously this result gets cached for future reference and speed.
However, I'm experiencing some issues whereby if the web.config gets updated (and, in some scarier instances if the application pool gets recycled) then it will lose all knowledge of certain assemblies, resulting in the inability to render an instance of the module type. Debugging shows that the missing assembly literally does not exist in the current thread assemblies list.
To get around this I added a second check which is a bit dirty but recurses through the /bin/ directory's DLLs and checks that each one exists in the assemblies list. If it doesn't, it loads it using Assembly.Load and fixing the context issue thanks to 'Solving the Assembly Load Context Problem'.
This would work, only it seems that (and I'm aware this shouldn't be possible) some projects still have access to the missing assembly, for example my actual web project rather than the framework itself - and it then complains that duplicate references have been added!
Has anyone ever heard of anything like this, or have any ideas why an assembly would simply drop out of existence on a config change? Short of a solution, what is the most elegant workaround to get all the assemblies in the bin to reload? It needs to be all in one "hit" so that the site visitors don't see any difference other than a small delay, so an app_offline.htm file is out of the question. Programatically renaming a DLL in the bin and then naming it back does work, but requires "modify" permissions for the IIS user account, which is insane.
Thanks for any pointers the community can gather!
Generally, you should avoid relying on what assemblies are currently loaded in an appdomain, as that happens dynamically. Instead, simply call System.Web.Compilation.BuildManager.GetType() instead of Type.GetType() or Assembly.GetType(). This should just do the right thing for you, and not be affected by appdomain cycles.
As you obviously know, there are many situations where the current appdomain is unloaded and reloaded. After each reload, all assemblies are unloaded and the whole application starts running "from scratch".
Assemblies are by default loaded on demand. Usually that is the case when the JIT stumbles across some reference. In consequence, a appdomain reload will clear out the assemblies in the appdomain and they will only appear again later on when the JIT loads them.
As solution I'd rever to using the static Type.GetType() method and supply an assembly qualified name (e.g. a type name with the assembly name included). That's the same thing the framework uses when loading types specified in the config file, and it will make sure that the required assembly is searched and loaded on demand without using any tricks. See the remarks section of the method above (the method name above name is a link).
This will require updates to your database to hold assembly qualified names instead of "only" fully qualified type names. However, it also makes sure that you don't run into name collisions when two assemblies provide different type with the same name, so this is a good idea anyways I think.
I've never heard of this problem before.
I'm not sure if this will work, as I only recently read about it while researching workarounds to ODAC dependencies, but specifying the probing path for assemblies may fix your issue.
see: http://msdn.microsoft.com/en-us/library/823z9h8w(VS.80).aspx
sample:
<configuration>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<probing privatePath="bin;bin2\subbin;bin3"/>
</assemblyBinding>
</runtime>
</configuration>
I have a similar problem, when I update 2-5 files, ether web.config, ether other files, and asp.net needs to recreate the running files, then some times did not find some classes/function that exist on dll files, and my system is not working - throw errors like yours.
My solution to that is that I place the app_offline.htm on the root, make my updates, then rename/remove the app_offline.htm and my system works fine.
I am sure that have something to do with the cached compiled files, but I did not have deaply search whats exactly cause that.
[what is the most elegant workaround to get all the assemblies in the bin to reload]
Now what is the most elegant workaround on this is to call the HttpRuntime.UnloadAppDomain and actually make your application to stop and starts again.
http://msdn.microsoft.com/en-us/library/system.web.httpruntime.unloadappdomain(VS.80).aspx
I do not know if this solve your issue, you need to make tests.
probably on Global.asax make something like that
void Application_Error(object sender, EventArgs e)
{
Exception ex = Server.GetLastError().GetBaseException();
...if ex is your error, and you get more than 2 ...
{
HttpRuntime.UnloadAppDomain();
}
}
I would try to create some basic class from which assembly, which is interesting for you without reflection on Application Start to make sure it is loaded.
E.g.
var temp = new BaseModuleBuilder();
This do not look smart, but it is very straitforward and asp.net should do everything for you. In case when your list is too dynamic, it could be something like
var temp = Activator.CreateInstance(Type.GetType("BaseModuleBuilder, Modules.dll"));
Make sure to always specify DLL when working with dynacmically loaded classes.

web.config - auto generate a release version

Simple task, but for some reason no simple solution just yet.
We've all got web.config files - and I haven't worked anywhere yet that doesn't have the problem where someone yells across the room "Sh*t, I've just uploaded the wrong web.config file".
Is there a simple way of being able to auto generate a web.config file that will contain the right things for copying to release? An example of these being:
Swap connection string over to use live database
Change
Switch over to use the live/release logging system, and live/release security settings
(in our case we need to change the SessionState mode to InProc from StateServer - this isn't normal)
If you have others, let me know and I'll update it here so it's easy for someone else to find
Maintaining 2 config files works, but is a royal pain, and is usually the reason something's gone wrong while you're pushing things live.
Visual Studio 2010 supports something like this. Check it out here.
How are you deploying your builds. In my environment, this used to be a pain point too, but now we use cruisecontrol.net and script our builds in nant. In our script, we detect the environment and have different versions of the config settings for each environment. See: http://www.mattwrock.com/post/2009/10/22/The-Perfect-Build-Part-3-Continuous-Integration-with-CruiseControlnet-and-NANT-for-Visual-Studio-Projects.aspx for my blogpost onthe subject of using cruisecontrol.net for build management. Skip to the end fora brief description of how we handle config versions.
In my most recent project I wrote a PowerShell script which loaded the web.config file, modified the necessary XML elements, and saved the file back out again. A bit like this:
param($mode, $src)
$ErrorActionPreference = "stop"
$config = [xml](Get-Content $src)
if ($mode -eq "Production")
{
$config.SelectSingleNode("/configuration/system.web/compilation").SetAttribute("debug", "false")
$config.SelectSingleNode("/configuration/system.web/customErrors").SetAttribute("mode", "off")
$config.SelectSingleNode("/configuration/system.net/mailSettings/smtp/network").SetAttribute("host", "live.mail.server")
$config.SelectSingleNode("/configuration/connectionStrings/add[#name='myConnectionString']").SetAttribute("connectionString", "Server=SQL; Database=Live")
}
elseif ($mode -eq "Testing")
{
# etc.
}
$config.Save($src)
This script overwrites the input file with the modifications, but it should be easy to modify it to save to a different file if needed. I have a build script that uses web deployment projects to build the web app, outputting the binaries minus the source code to a different folder - then the build script runs this script to rewrite web.config. The result is a folder containing all the files ready to be placed on the production server.
XSLT can be used to produce parameterized xml files. Web.config being xml file this approach works.
You can have one .xslt file(having xpath expressions).
Then there can be different xml files like
1. debug.config.xml
2. staging.config.xml
3. release.config.xml
Then in the postbuild event or using some msbuild tasks the xslt can be combined with appropriate xml files to having different web.config.
Sample debug.config.xml file can be
<Application.config>
<DatabaseServer></DatabaseServerName>
<ServiceIP></ServiceIP>
</Application.config>
.xslt can have xpaths referring to the xml given above.
Can have a look at the XSLT transformation This code can be used in some MSBuild tasks or nant tasks and different web.config's can be produced depending on the input config xml files.
This way you just have to manage the xml files.
There is only one overhead that the xslt file which is similar to web.config need to be managed. i.e whenever there is any tag getting added in the web.config the xslt also needs to be changed.
I don't think you can 100% avoid this.
The last years of work ever and ever shows: where human worked, there are fails.
So, here are 3 ideas from my last company, not the best maybe, but better then nothing:
Write an batch file or an C#.Net Application that change your web.config on a doubleclick
Write a "ToDo on Release"-List
Do pair-realesing (== pair programming while realease :))

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