I would like to give my CSS and javascript files far-future headers and add a token onto the URLs referrring to them. That way browsers don't have to re-download CSS and javascript unless I've released a new build of the site.
http://example.com/css/styles.css?build=23424
How can I pass a build number or timestamp to my code-behind so it can add the timestamp?
Obviously C# doesn't have macros, which is what I would use in C/C++.
I realise that this will force browsers to download assets whenever I do a new build - regardless of whether or not the build involved changing the assets. However, I would like to put a simple scheme in place before I implement anything more advanced like looking at individual file modification times.
Here's a bit of code that I use to extract the build id from the current assembly at application start. It reads the version number from the assembly, a version designator (dev/qa/blank) from the web config, then constructs a version number string to stuff into the application. This code goes in Global.asax.cs. You can then refer to it in your markup from the Application instance.
var webAssembly = Assembly.GetAssembly( typeof(...known class...) );
var designator = WebConfigurationManager.AppSettings["VersionDesignator"];
string version = webAssembly.GetName().Version + designator;
this.Application.Add( "Version", version );
Here's an example of how you could use it in an MVC context (sorry I don't have any WebForms examples).
<link type="text/css" rel="stylesheet"
href="/Content/styles/screen.css?build=<%= this.Application["Version"] %>" />
Interesting idea.
Here's one way to do it:
Go into your AssemblyInfo.cs class under the Properties folder in your project.
Change your assembly version to include the star wildcard: [assembly: AssemblyVersion("1.0.*")].
In your code, you can retrieve the current build version like this:
_
var buildNumber = Assembly.GetExecutingAssembly().GetName().Version.Build;
_
That's it, you're done.
Changing the AssemblyVersion to 1.0.* will cause Visual Studio/MSBuild to increment the build number automatically for you each build. Then, you can access this build number at runtime using the above code snippet. Easy as cheese.
Browsers and servers know how to handle caching via HTTP. So, I misunderstand, what are you trying to accomplish with providing this kind of caching. A browser will not re-download your CSS and Javascript if it has seen it recently. And it will re-download it if you do a push of your new build on the server. See cache headers like Cache-control and Expires etc. Here's a tutorial http://www.mnot.net/cache_docs/
Related
I created a new .NET 6 Blazor Server-side project and made a couple of changes. I have a couple of files using CSS isolation (like Contact.razor + Contact.razor.css).. In the _Layout.cshtml page the template added the following:
<link href="CustomerPortal.styles.css" rel="stylesheet" />
Where CustomerPortal is my Project Name. I can see the file is generated correctly under "CustomerPortal\CustomerPortal\obj\Debug\net6.0\scopedcss\projectbundle\CustomerPortal.bundle.scp.css" and "C:\Data\Git\WebApps\CustomerPortal\CustomerPortal\obj\Debug\net6.0\scopedcss\bundle\CustomerPortal.styles.css"
BUT when I run the project, both with Kernel or IIS Express, I get a 404 not found for the CSS, if I try to manually navigate to the CSS I also can't find it. Any ideas? My csproj doesn't have any flags that would affect it.
Edit:
There is a new extension as part of the minimal setup in .NET 7, and backported to newer versions of .NET 6 as well.
Both in .NET 7 and .NET 6 you can now do:
builder.WebHost.UseStaticWebAssets();
Old answer:
You've got a couple options here to resolve this depending on the approach you want to take. I think we've figured out why it's happening, but UseStaticWebAssets() seems to not be supported for the new minimal startup code. So, here's your options I can think of off the top of my head.
Migrate your code back to the "old" way of doing application startup. This is still a supported and completely valid approach as there's edge cases that aren't supported (like this one).
Pass a new WebApplicationOptions to the CreateBuilder() method and, depending on environment, look for the static files in a separate (and correct) location. See some examples here.
With the existing builder, check the environment and use the StaticWebAssetsLoader to load static web assets.
A complete example of #3
if (builder.Environment.IsEnvironment("Local"))
{
StaticWebAssetsLoader.UseStaticWebAssets(builder.Environment, builder.Configuration);
}
That being said - I'd imagine they'll plug this hole eventually and provide parity for UseStaticWebAssets(). You can see the progress of this effort in this open GitHub issue.
For anyone else...
I had the exact same issue with a .net 6 blazor server app. For me it came down to the fact that I had changed the project name but the reference to {project}.styles.css in _Layout.cshtml was still pointing to the old project name.
Simply updating {project} here to the correct project name fixed my issue.
When I encountered this error, it was because I'd named my MVC project with a hyphen: htmx-spike.
When I generated the project from a template (dotnet new mvc -o htmx-spike), the tooling renamed the namespace to htmx_spike—with an underscore instead of a hyphen, because hyphens aren't allowed in C# identifiers—and used that modified name as the CSS filename in _Layout.cshtml.
However, it turns out that in this case the CSS location actually still corresponds with the project name, with the hyphen. So the auto-generated code is incorrect, and was causing the 404 to be returned:
Once I renamed the file in the link element to the correct name with the hyphen, everything was fine.
I had the same issue with a component I imported from another project. I solved it by closing all instances of Visual Studio, deleting the hidden folder [.vs] from the project folder, and then restarting the project in Visual Studio. On restart, Visual Studio recreated that folder and imported CSS file(s) were included.
I've recently started using Xamarin/MonoDevelop as an alternative to Microsoft Visual Studio and my first project was to create a website using ASP.NET with MVC pattern. This has been going well, and I don't mind the extra code work, but I'm having a rough time with the CSS.
For whatever reason, any CSS file only seems to compile once, ignoring any changes I write to the file. From my research, this because content files are cached for the build.
Is there a method in Xamorin's files, Microsoft's aspnet and web packages, or Newtonsoft's or Razor's library? If so, in which part of my solution do I call it?
Is there an add-on to Xamarin? How do I use it?
Do I have to modify a config file?
As pointed out in the comments, the issue was being caused by the browser cache not refreshing with changes to the build. The solution to this is to append a version to the end of the path name for the stylesheet. Since I am using cshtml, I decided to use this:
<head>
#{
string version = "?v=2";
string stylePathSite = "../../Content/Styles/SiteStyles.css" +
version;
string stylePathNav = "../../Content/Styles/NavBarStyles.css" +
version;
}
<link rel="stylesheet" href="#stylePathSite"/>
<link rel="stylesheet" href="#stylePathNav"/>
</head>
I can later write a controller to be update the version variable from my model. Hope any fellow newbies out there find this helpful.
So I created an ASP.NET 4 application in VS2010, that needs to play sound to the end user, and it is working perfectly in my local development environment. The problem is the sound resource nor the Resources.resx is not being published to the server. Any idea why?
What I did:
1) Under Project Properties Recources I added my sound resource called: soundbyte (containing soundbyte.wav). I noticed this creates a Resource folder with the wav file and under my project a Resources.resx file referencing the file
2) In my code I play the file as follows:
Dim audioFile = My.Resources. soundbyte
Dim player = New Media.SoundPlayer(audioFile)
player.Load()
player.Play()
In the Visual Studio Solution Explorer right-click on Resources.resx and select Properties. Build Action. Set to content.
EDIT: The following resource might also help.
http://blog.andreloker.de/post/2010/07/02/Visual-Studio-default-build-action-for-non-default-file-types.aspx
Ultimately, I found a way to play the sound to the client browser (as opposed to the server the asp app is running on) was to follow the techniques in this example: http://www.vbdotnetheaven.com/UploadFile/scottlysle/PlaySoundsInASPX09032006083212AM/PlaySoundsInASPX.aspx
But I found an even better way in my case was to use Javascript, which doesnt' require the Resources technique.
simply embed the sound on the page after the tag:
<embed src="Sounds/jump.wav" autostart=false width=1 height=1 id="sound1" enablejavascript="true">
Then in javascript setup the function:
function EvalSound(soundobj) {
var thissound=document.getElementById(soundobj);
thissound.Play();
}
Finally play the sound in the browser as needed in Javascript:
EvalSound('sound1');
I want to make a "properties style web form" that shows the application version for various .NET applications.
If I know the URL e.g. /someapp/default.aspx is it possible via reflection to execute that page and figure out the assembly version?
It's quite easy to find the executing assembly version, but without modifying the other application, is it possible?
Both the property page and the other application is running on the same server and in the same application pool.
Update: I've had some luck with
var url = "~/SomeApp/default.aspx";
var appType = System.Web.Compilation.BuildManager.GetCompiledType(url);
But navigating appType to find the assembly file version is not the same everytime.
Without modifying the web application to expose the version number through some URL-based retrieval (a simple page GET being the easy, obvious one), you're going to need to find a way to figure out where the DLL for the web application is from the URL.
If you can know the DLL's location, either by some convention (e.g. /appX/ is always at D:\Sites\appX\bin\appX.dll) or some configuration (you manually enter where each URL base's DLL is in a database), then you can retrieve that DLL's assembly version using the following code:
Assembly assembly = Assembly.LoadFrom("MyAssembly.dll");
Version ver = assembly.GetName().Version;
Code taken from this question.
Edit:
I've had a little look around, and there are some APIs to inspect the IIS configuration, so this is certainly a route to explore if you're trying to get from the URL to the assembly location. This question has an example of getting the physical path from the application/site name, for example. Microsoft.Web.Administration is the assembly to explore.
The ASP.NET engine streams nothing but HTML, javascript, etc.. to the client. There is nothing left of the assembly that gets passed in the response that can show what version of .net/asp.net that the application is running unless the developer on the server side adds it.
That said, you can gather some information from a utility at http://uptime.netcraft.com/up/graph that will give you some server information. Not down to the assembly version, but this is as close as I believe you are going to get.
You may implement custom HttpModule, put it to the bin folder of each application that you wish to monitor and append register this module in web.config files. In this module for example you should handle request, retrieve all required information and put it to response cookie.
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 :))