drn-buildwww-vite

name	drn-buildwww-vite
description	DRN buildwww Vite build system - multi-build configuration, TypeScript aliases, wwwroot output, appPreload/appPostload, and Vite manifest discovery. Keywords: drn, buildwww, vite, typescript, bundling, asset-compilation, npm, javascript, css, scss, build-pipeline, entry-points, manifest
last-updated	"2026-07-07T00:00:00.000Z"
difficulty	intermediate
tokens	~2K

DRN buildwww & Vite

Frontend build system using Vite and TypeScript for repositories that declare the DRN buildwww convention.

When to Apply

• Configuring frontend build
• Adding new JavaScript/TypeScript files
• Modifying Vite build configuration
• Working with path aliases
• Understanding build output structure

---

Directory Structure

<frontend-package>/
├── buildwww/                # Source files (not served)
│   ├── app/                 # Application code
│   │   ├── js/              # JavaScript modules
│   │   │   ├── drn/         # Application utilities
│   │   │   ├── appPreload.js
│   │   │   └── appPostload.js
│   │   └── css/             # Application CSS
│   ├── lib/                 # Library code
│   │   ├── htmx/            # htmx bundle
│   │   ├── bootstrap/       # Bootstrap customization
│   │   └── react/           # React mounted islands (Shadow DOM + Tailwind)
│   ├── plugins/             # Vite plugins
│   └── types/               # TypeScript declarations
├── wwwroot/                 # Built output (served)
│   ├── app/                 # Built app files
│   └── lib/                 # Built library files
├── vite.config.js           # Vite configuration
├── tsconfig.json            # TypeScript configuration
├── package.json             # npm dependencies
└── package-lock.json

---

Vite Configuration

Multi-Build Setup

// vite.config.js — uses rolldownOptions (Vite 6+ with Rolldown)
const builds = {
    app: {
        plugins: [iifeWrap()],
        build: {
            outDir: 'wwwroot/app',
            rolldownOptions: {
                input: {
                    app: resolve(__dirname, 'buildwww/app/css/app.css'),
                    appPreload: resolve(__dirname, 'buildwww/app/js/appPreload.js')
                }
            }
        }
    },
    appPostload: {
        plugins: [iifeWrap()],
        build: {
            outDir: 'wwwroot/appPostload',
            rolldownOptions: {
                input: {
                    appPostload: resolve(__dirname, 'buildwww/app/js/appPostload.js')
                }
            }
        }
    },
    htmx: {
        plugins: [iifeWrap(), stripHtmxEval()],
        build: {
            outDir: 'wwwroot/lib/htmx',
            rolldownOptions: {
                input: {
                    htmxBundle: resolve(__dirname, 'buildwww/lib/htmx/htmxBundle.js')
                }
            }
        }
    },
    bootstrap: {
        build: {
            outDir: 'wwwroot/lib/bootstrap',
            rolldownOptions: {
                input: {
                    bootstrap: resolve(__dirname, 'buildwww/lib/bootstrap/bootstrap.scss'),
                    bootstrapBundle: resolve(__dirname, 'buildwww/lib/bootstrap/bootstrapBundle.js')
                }
            }
        },
        plugins: [iifeWrap()]
    },
    react: {
        plugins: [react(), tailwindcss()],
        build: {
            outDir: 'wwwroot/lib/react',
            rolldownOptions: {
                input: {
                    reactBundle: resolve(__dirname, 'buildwww/lib/react/reactBundle.tsx')
                },
                output: { format: 'iife', name: 'DrnReactMicroFrontend' }
            }
        }
    }
};

// Select build via environment variable
const buildType = process.env.BUILD_TYPE || 'app';

See drn-buildwww-react for the full React build architecture (Shadow DOM, Tailwind 4, IIFE format rationale).

Build Commands

Repository rule: do not run build commands unless the user explicitly allows them.

# Build all targets
npm run build

# Or build individual targets
npm run build:app
npm run build:appPostload
npm run build:htmx
npm run build:bootstrap
npm run build:react

CI validation runs .github/actions/frontend-build in parallel with backend checks. Release workflows run it before .NET build/test and publishing so generated wwwroot assets stay in the release job workspace.

Shared Configuration

const sharedConfig = {
    base: '/',
    build: {
        emptyOutDir: true,
        manifest: true,
        rolldownOptions: {
            output: {
                entryFileNames: `[name].[hash:16].js`,
                chunkFileNames: `[name].[hash:16].js`,
                assetFileNames: `[name].[hash:16].[ext]`
            }
        }
    },
    resolve: {
        alias: {
            '@css': resolve(__dirname, 'buildwww/app/css'),
            '@js': resolve(__dirname, 'buildwww/app/js'),
            '@lib': resolve(__dirname, 'buildwww/lib'),
            '@types': resolve(__dirname, 'buildwww/types'),
            '@plugins': resolve(__dirname, 'buildwww/plugins')
        }
    }
};
// Per-build configs are deep-merged with sharedConfig
export default defineConfig(drnUtils.deepMerge(sharedConfig, builds[buildType]));

Note: TypeScript path alias @/* → buildwww/* is configured in tsconfig.json and resolved by moduleResolution: "bundler". The Vite resolve.alias entries above mirror the actual buildwww/app, buildwww/lib, buildwww/types, and buildwww/plugins layout. No root buildwww/js, buildwww/css, buildwww/ts, or buildwww/scss directories are assumed.

---

TypeScript Configuration

{
  "compilerOptions": {
    "target": "ES2023",
    "module": "ESNext",
    "moduleResolution": "bundler",
    "strict": true,
    "noEmit": true,
    "allowJs": true,
    "allowImportingTsExtensions": true,
    "verbatimModuleSyntax": true,
    "lib": ["ES2023", "DOM", "DOM.Iterable"],
    "baseUrl": ".",
    "paths": {
      "@/*": ["buildwww/*"],
      "@js/*": ["buildwww/app/js/*"],
      "@css/*": ["buildwww/app/css/*"],
      "@lib/*": ["buildwww/lib/*"],
      "@types/*": ["buildwww/types/*"],
      "@plugins/*": ["buildwww/plugins/*"]
    },
    "typeRoots": ["./buildwww/types", "./node_modules/@types"]
  },
  "include": [
    "buildwww/app/**/*",
    "buildwww/lib/**/*",
    "buildwww/types/**/*"
  ],
  "exclude": ["node_modules", "wwwroot/dist"]
}

---

Package Configuration

Detailed package versioning and dependency definitions are managed in:

• drn-buildwww-packages.md

---

Entry Points

Current builds are app, appPostload, htmx, bootstrap, and react.

appPreload.js

Loaded early, before page content:

• Critical initializations
• Theme setup
• Cookie consent checks

appPostload.js

Loaded after page content:

• Event handlers
• DOM manipulations
• Non-critical scripts

---

Output Structure

wwwroot/
├── app/
│   ├── appPreload.[hash].js
│   ├── app.[hash].css
│   └── .vite/manifest.json
├── appPostload/
│   ├── appPostload.[hash].js
│   └── .vite/manifest.json
├── lib/
│   ├── htmx/
│   │   ├── htmxBundle.[hash].js
│   │   └── .vite/manifest.json
│   ├── bootstrap/
│   │   ├── bootstrap.[hash].css
│   │   ├── bootstrapBundle.[hash].js
│   │   └── .vite/manifest.json
│   └── react/
│       ├── reactBundle.[hash].js
│       └── .vite/manifest.json

---

Using Built Assets in Razor

<script src="buildwww/app/js/appPreload.js"></script>
<link href="buildwww/app/css/app.css" rel="stylesheet" />
<link href="buildwww/lib/bootstrap/bootstrap.scss" rel="stylesheet" />
<script src="buildwww/lib/htmx/htmxBundle.js"></script>
<script src="buildwww/lib/bootstrap/bootstrapBundle.js"></script>
<script src="buildwww/app/js/appPostload.js"></script>
<script src="buildwww/lib/react/reactBundle.tsx"></script>

TagHelpers resolve these source paths through the per-output .vite/manifest.json files and emit content-hashed wwwroot paths with SRI where applicable.

Runtime manifest discovery is source-owned by DRN.Framework.Hosting.Utils.Vite.ViteManifest. DRN Hosting currently discovers Vite's default .vite/manifest.json files below the active web root, or ContentRootPath/wwwroot when the web root is empty. When changing environment defaults, publish behavior, or static-web-asset roots, verify that the running app can still see the Vite manifests; a rendered page can otherwise be missing CSS/JS even when server startup succeeds.

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Related Skills

• overview-ddd-architecture.md - Architecture guidance
• drn-buildwww-libraries.md - Library usage
• drn-buildwww-react.md - React build architecture
• drn-buildwww-packages.md - Package dependencies
• frontend-razor-pages-shared.md - Layout integration

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