vite-plugin-singlefile

This Vite build plugin allows you to inline all JavaScript and CSS resources directly into the final dist/index.html file. By doing this, your enter web app can be embedded and distributed as a single HTML file.

Why?

Bundling your entire site into one file certainly isn't recommended for most situations.

However, this can be very handy for offline web applications--apps you can simply opeen the HTML file in your default web browser. This might include utilities, expert system tools, documentation, demos, and other situations where you want the full power of a web browser, without the need for a Cordova or Electron wrapper or the pain of normal application installation.

Limitations

Web applications running from a local file have some browser security limitations:

No ability to access external domains -- no images, no API calls, etc.
Limited state management options -- no cookies, no localStorage. However, you can use the new FileSystem API, with user permission.
Some web features that require a secure context may not be available.

How do I use it?

Here's an example vite.config.ts file.

import { defineConfig } from "vite"
import vue from "@vitejs/plugin-vue"
import { viteSingleFile } from "vite-plugin-singlefile"

export default defineConfig({
	plugins: [vue(), viteSingleFile()],
	build: {
		target: "esnext",
		assetsInlineLimit: 100000000,
		chunkSizeWarningLimit: 100000000,
		cssCodeSplit: false,
		brotliSize: false,
		rollupOptions: {
			inlineDynamicImports: true,
			output: {
				manualChunks: () => "everything.js",
			},
		},
	},
})

The cssCodeSplit option results in all CSS being emitted as a single file, which vite-plugin-singlefile can then inline.
The assetsInlineLimit ensures that even very large assets are inlined in your JavaScript.
The inlineDynamicImports also ensures that as many resources as possible are inlined.
The manualChunks option became necessary somewhere around Vite 2.0 release to prevent the creation of a separate vendor.js bundle. outputOptions became just output some time after that.
The brotliSize option just avoids the extra step of testing Brotli compression, which isn't really pertinent to a file served locally.
The chunkSizeWarningLimit option just avoids the warnings about large chunks.
The filename you choose for manualChunks ultimately doesn't matter, it will get rolled into index.html by the plugin.

Caveats

favicon resources are not inlined by Vite, and this plugin doesn't do that either.
There may be other situations where referenced files aren't inlined by Vite and aren't caught by this plugin either. I've done little testing so far, I just wanted to get this out there first.
This is my first Vite and first Rollup plugin. I have no idea what I'm doing. PRs welcome.
This doesn't remove the build artifacts from the dist folder, it just embeds them in the index.html. You can ignore the extra files. I'd be open to a PR to remove the recognized files so the dist folder is cleaner, especially if there's a way to just prevent them from being written in the first place (i.e., not having to delete the files).

Installation

yarn add vite-plugin-singlefile -D or npm i vite-plugin-singlefile -D

License

MIT