MonorailCss.Discovery 0.1.3

MonorailCSS.Discovery

Runtime CSS class discovery for MonorailCSS. It scans the IL of loaded assemblies — plus any source files you point it at — to find the utility classes your app actually uses, then compiles them with MonorailCSS. No source generators, no MSBuild tasks, no Node toolchain.

This is the companion package for development-time and runtime CSS generation (e.g. a Blazor app serving /css/app.css live with hot reload). For build-time CSS generation that ships a static stylesheet, use MonorailCss.Build.Tasks instead.

What it scans

• Loaded assemblies via in-memory metadata (Assembly.TryGetRawMetadata) — class-shaped string literals baked into .razor/.cs compiled output, including those in referenced NuGet packages.
• Source files (.razor, .cshtml, .cs, .html, …) for live class extraction during development. Under dotnet watch this reaches across project boundaries: the source directories of referenced, locally-built projects (located from their build PDBs) are watched too, so editing a component in a referenced library regenerates CSS even though its source lives outside the running app.
• Static web assets (.js/.mjs shipped by Razor Class Libraries under _content/), so component libraries that build markup at runtime are covered.

Assemblies marked [assembly: MonorailCssNoScan] — including the MonorailCSS framework assemblies — are skipped automatically. Framework assemblies (Microsoft.*, System.*, …) are excluded by default. You can exclude additional assemblies (e.g. icon packs whose IL is full of class-shaped strings) via options.

Basic usage (ASP.NET Core / Blazor)

builder.Services.AddMonorailCssDiscovery(options =>
{
    options.SourceCssPath = "wwwroot/app.css"; // @theme / @apply / @utility / @source directives
});

// ...
app.MapMonorailCss("/css/app.css"); // serves generated CSS, regenerates on change in development

In your markup, reference the endpoint exactly as you would a static stylesheet:

<link rel="stylesheet" href="/css/app.css" />

A common pattern is hybrid: run Discovery in Development for instant feedback, and let MonorailCss.Build.Tasks emit a static app.css for Release so production serves a plain file with no scanning at startup.

See the MonorailCSS documentation for configuration, theming, and the full directive reference.