Vite Integration For Go

A Go module that lets you serve your Vue 3, React, or Svelte project from a Go-based web server. You build your project, tell Go where to find the dist/ directory, and the module figures out how to load the generated Vue application into a web page.

Installation

go get github.com/torenware/vite-go

To upgrade to the current version:

go get -u github.com/torenware/vite-go@latest 

Getting It Into Your Go Project

The first requirement is to use ViteJS's tooling for your JavaScript code. The easiest thing to do is either to start out this way, or to create a new project and move your files into the directory that Vite creates. Using NPM:

npm create vite@latest

Using Yarn:

yarn create vite

Just answer the questions asked, and away you go.

You will need to position your source files and the generated dist/ directory so Go can find your project, the manifest.json file that describes it, and the assets that Vite generates for you. You may need to change your vite.config.js file (vite.config.ts if you prefer using Typescript) to make sure the manifest file is generated as well. Here's what I'm using:

/**
 * @type {import('vite').UserConfig}
 */
import { defineConfig } from 'vite';
import vue from '@vitejs/plugin-vue';

export default defineConfig({
  plugins: [vue()],
  build: {
    manifest: 'manifest.json',
    rollupOptions: {
      input: {
        main: 'src/main.ts',
      },
    },
  },
});

This, however, is more than you need. A minimal config file would be:

import { defineConfig } from 'vite'
import vue from '@vitejs/plugin-vue'

// https://vitejs.dev/config/
export default defineConfig({
  plugins: [vue()],
  build: {
    manifest: "manifest.json",
  },
})

The essential piece here is the vue plugin (or whatever plugin you need instead for React, Preact or Svelte) and the build.manifest line, since vite-go needs the manifest file to be present in order to work correctly.

Here's some sample pseudo code that uses the go 1.16+ embedding feature for the production build, and a regular disk directory (frontend in our case) as a development directory:

package main

import (
  "embed"
  "html/template"
  "net/http"

  vueglue "github.com/torenware/vite-go"
)

//go:embed "dist"
var dist embed.FS

var vueGlue *vueglue.VueGlue

func main() {
    
    // This:
    
    // Production configuration.
    config := &vueglue.ViteConfig{
        Environment: "production",
        AssetsPath:  "dist",
        EntryPoint:  "src/main.js",
        Platform:    "vue",
        FS:          frontend,
    }

    // OR this:
    
    // Development configuration
    config := &vueglue.ViteConfig{
        Environment: "development",
        AssetsPath:  "frontend",
        EntryPoint:  "src/main.js",
        Platform:    "vue",
        FS:          os.DirFS("frontend"),
    }

  // Parse the manifest and get a struct that describes
  // where the assets are.
  glue, err := vueglue.NewVueGlue(config)
  if err != nil {
    //bail!
  }
  vueGlue = glue
  
  // and set up your routes and start your server....
  
}

func MyHandler(w http.ResponseWriter, r *http.Request) {
  // Now you can pass the glue object to an HTML template
  ts, err := template.ParseFiles("path/to/your-template.tmpl")
  if err != nil {
      // better handle this...
  }
  ts.Execute(respWriter, vueGlue)

}

You will also need to serve your javascript, css and images used by your javascript code to the web. You can use a solution like http.FileServer, or the wrapper the library implements that configures this for you:

   // using the standard library's multiplexer:
    mux := http.NewServeMux()

    // Set up a file server for our assets.
    fsHandler, err := glue.FileServer()
    if err != nil {
        log.Println("could not set up static file server", err)
        return
    }
    mux.Handle("/src/", fsHandler)

Some router implementations may alternatively require you to do something more like:

// chi router
mux := chi.NewMux()

...

mux.Handle("/src/*", fsHandler)

YMMV :-)

Templates

Your template gets the needed tags and links by declaring the glue object in your template and calling RenderTags on, as so:

<!doctype html>
<html lang='en'>
{{ $vue := . }}
    <head>
        <meta charset='utf-8'>
        <title>Home - Vue Loader Test</title>
        
        {{ if $vue }}
          {{ $vue.RenderTags }}
        {{ end }}
        
    </head>
    <body>
      <div id="app"></div>
      
    </body>
  </html>
      
 

You should check that the glue ($vue in our example) is actually defined as I do here, since it will be nil unless you inject it into your template.

The sample program in examples/sample-program has much more detail, and actually runs.

Configuration

Vite-Go is fairly smart about your Vite Javascript project, and will examine your package.json file on start up. If you do not override the standard settings in your vite.config.js file, vite-go will probably choose to do the appropriate thing.

As mentioned above, a ViteConfig object must be passed to the NewVueGlue() routine, with anything you want to override. Here are the major fields and how to use them:

Caveats

This code is relatively new; in particular, there may be some configurations you can use in vite.config.js that won't work as I expect. If so: please open an issue on Github. I've posted the code so people can see it, and try things out. I think you'll find it useful.

Copyright © 2022 Rob Thorne

MIT License