AspNetCore.SassCompiler

Sass Compiler Library for .NET 6 and above, without node.

Installation

The installation of this package is quite simple, you can install this package using NuGet with the following command:

# Package Manager
PM> Install-Package AspNetCore.SassCompiler

# .NET CLI
dotnet add package AspNetCore.SassCompiler

Configuration

After adding the package, the Sass styles from the Source (defaults to: Styles) will automatically be compiled into .css files in the TargetFolder (defaults to: wwwroot\css) on build. You can also adjust the default configuration in the appsettings.json or sasscompiler.json, do note that when using appsettings.json the configuration needs to be nested under a "SassCompiler" property, but when you're using sasscompiler.json the settings should not be nested.

Available options

Name	Default value	Description
Source	"Styles"	The folder where all the .scss files reside, or an scss file
Target	"wwwroot/css"	When Source is a folder, the folder to output the generated .css files to When Source is a file, the .css filepath where to save the css file
Arguments	"--error-css"	Arguments passed to the dart-sass executable. see here for available arguments.
GenerateScopedCss	true	Enable/disable support for scoped scss
ScopedCssFolders	["Views", "Pages", "Shared", "Components"]	The folders in which .scss files are considered for scoped css
IncludePaths	[]	Add folders to search in when importing modules
Compilations	[]	A list of source/target pairs that should be compiled. These will be added to the default Source and Target configured above.
Configurations	{}	Add configuration to override specific options based on the build conifguration (e.g. Debug/Release)

Examples

appsettings.json

{
  "SassCompiler": {
    "Source": "Styles",
    "Target": "wwwroot/css",
    "Arguments": "--style=compressed",
    "GenerateScopedCss": true,
    "ScopedCssFolders": ["Views", "Pages", "Shared", "Components"],
    "IncludePaths": [],
    
    "Compilations": [
      // Specify a specific file source/target in addition to the "Styles" -> "wwwroot/css" Source/Target above
      { "Source":  "wwwroot/scss/site.scss", "Target":  "wwwroot/css/site.min.css" },
      // Or an extra directory to a different target directory
      { "Source":  "Lib/Styles", "Target":  "wwwroot/lib/css" }
    ],

    // You can override specific options based on the build configuration
    "Configurations": {
      "Debug": { // These options apply only to Debug builds
        "Arguments": "--style=expanded"
      }
    }
  }
}

sasscompiler.json

{
  "Source": "Styles",
  "Target": "wwwroot/css",
  "Arguments": "--style=compressed",
  "GenerateScopedCss": true,
  "ScopedCssFolders": ["Views", "Pages", "Shared", "Components"],
  "IncludePaths": [],

  "Compilations": [
    // Specify a specific file source/target in addition to the "Styles" -> "wwwroot/css" Source/Target above
    { "Source":  "wwwroot/scss/site.scss", "Target":  "wwwroot/css/site.min.css" },
    // Or an extra directory to a different target directory
    { "Source":  "Lib/Styles", "Target":  "wwwroot/lib/css" }
  ],
  
  // You can override specific options based on the build configuration
  "Configurations": {
    "Debug": { // These options apply only to Debug builds
      "Arguments": "--style=expanded"
    }
  }
}

Sass watcher

To use the Sass watcher in your project, you must add the following code to your startup.cs:

public void ConfigureServices(IServiceCollection services) 
{
  
#if DEBUG
  services.AddSassCompiler();
#endif

}

We recommend adding the #if DEBUG statement to only use a watcher during debug mode.

Note: The Sass watcher is currently not supported inside of a docker container. This should only be an issue when you're developing inside of a docker container, running the published application in docker is supported as the compiler is automatically run during the MSBuild publish step. See this issue for the progress.

Blazor WASM

If you use this with Blazor WebAssembly and want to customize the settings you need to use the sasscompiler.json, using appsettings.json is not supported. The sass watcher is currently not supported for Blazor WebAssembly projects, the MSBuild task is still available and will compile your scss during build and publish.

Compiling SCSS at runtime

It is also possible to compile SCSS files at runtime by using the ISassCompiler interface. By default however, the sass executables are not included in a Release build. To make be able to use the ISassCompiler interface in production you need to add the following property to your csproj file: <SassCompilerIncludeRuntime>true</SassCompilerIncludeRuntime>.

If you don't want to use the hosted service to automatically compile your scss files during development, but do want to have the ISassCompiler available, you can use the AddSassCompilerCore() method instead of the AddSassCompiler() method on the IServiceCollection. This will register what is required to use the ISassCompiler interface without registering the hosted service.

Publish

This library also includes an MSBuild task that runs during the publish of your application. Because of this you don't need to include the Sass Watcher in your release builds and you can safely add the generated .css files to the .gitignore file as they are regenerated during publish.

Alpine linux

If you're publishing your application inside an alpine linux container, you will need to install gcompat (using apk add gcompat) before running dotnet build or dotnet publish. This is needed because the dart runtime which is what the sass compiler uses requires this package on alpine linux.

Examples

Take a look at one of our examples on how it can be integrated in your project. We've created example projects for ASP.NET Core MVC, Blazor Server/Wasm and RazorClassLibrary projects.

MVC

Blazor Server

Blazor WASM

Razor Class Library