0.0
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Get vue-cli working with Rails
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 Dependencies

Development

~> 1.12
~> 10.0
~> 3.0

Runtime

 Project Readme

VueCli::Rails

Build Status

Let's make cool boy Vue even cooler on Rails!

Change Log

Installation

Add this line to your Rails application's Gemfile:

gem 'vue_cli-rails'

And then execute:

$ bundle install

Requirements

  • Ruby >= 2.3
  • Rails >= 4.2
  • Node >= 8.9+
  • Optional: yarn

Features

  • Feel free to use yarn or npm.

  • Single vue_entry rather than confusing javascript_packs_with_chunks_tag, stylesheet_pack_tag, javascript_packs_tag, etc.

  • Get all benefits of Vue CLI.

    • Powered by webpack 4
    • DRY: all-in-one configuration file rather than repeating for webpack, eslint and etc.
    • Out-of-box tooling: Babel, TypeScript, PWA, vue-router, Vuex, CSS pre-processors, linter and testing tools.
    • Enhanced alias support in jest.config.js.
  • Run webpack-dev-server together with Rails server in dev mode.

  • Just single RAILS_ENV, no more NODE_ENV.

  • Rails way configurations in config/vue.yml.

Getting started

Out-of-box workflow:

  1. Make sure @vue/cli already installed globally via npm (npm i -g @vue/cli) or yarn (yarn global add @vue/cli)

  2. bundle exec rake vue:create and follow the steps.

    Don NOT select In package.json for "Where do you prefer placing config for Babel, PostCSS, ESLint, etc.?". Some functionalities like alias of jest may not work.

  3. Put your JavaScript files under app/assets/vue/entry_points.

  4. Insert your entry point by vue_entry 'entry_point' in views or render vue: 'entry_point' in controllers.

  5. webpack-dev-server auto starts alongside rails server in dev mode.

  6. Invoke env RAILS_ENV=production bundle exec rake vue:compile to compile assets (you still must manually set RAILS_ENV to production).

More settings are available in config/vue.yml

Usage

Core

Concept: Entry Point and File structure

The root path of your Vue assets is app/assets/vue. This gem will generate several folders. However, app/assets/vue/entry_points is the only one matters.

The entry path is configurable in config/vue.xml.

Webpack sees one JavaScript file as the center of a web page rather than HTML. Thus all styles, images, fonts and other assets are related to a JS files by import 'css/png/svg/woff2/json'. Any .js file under app/assets/vue/entry_points will be a entry-point.

Please ONLY puts your entry-point files under entry folder with .js extension name.

Be aware, .js.erb and .vue.erb are NOT supported. I will explain the reason in Q&A section.

If you are new to modern front-end development, or more specifically with webpack in this case, please read Q&A section for more information.

Helper vue_entry

vue_entry is like javascript_include_tag and stylesheet_link_tag which generates relative assets links for your entry point. (It's like javascript_packs_with_chunks_tag in Webpacker 4. I will explain why it's different in Q&A.)

You may have interest of path alias in config/vue.yml.

Use render vue: <entry_point> in controllers

Usually you only need <div id="app"></div> and vue_entry 'entry/point' to render a Vue page. You can use render vue: 'entry/point' inside your controller.

This method is simply a wrap of render html: vue_entry('entry_point'), layout: true. So you can pass any arguments supported by render including layout.

For example
# app/controllers/my_vue_controller
class MyVueController < ApplicationController
  layout 'vue_base'

  def foo
    render vue: 'foo/bar'
  end
end
<!-- app/views/layouts/vue_base.erb -->
<!DOCTYPE html>
<html>
<head>
  <title>My Vue</title>
</head>
<body>
  <div id="app"></div>
  <%= yield %>
</body>
</html>
// app/assets/vue/entry_points/foo/bar.js

import Vue from 'vue';

import Bar from '../views/Bar.vue';

Vue.config.productionTip = false;

new Vue({
  render: h => h(Bar),
}).$mount('#app');

Public Output Path

If the default setting vue_assets does not bother you at all, you can ignore this section.

Actually public_output_path in config/vue.yml is very simple - just a sub path under public directory. You might suffer some problems by changing it without understanding how it works:

  • My regular assets no longer work in dev mode server.
  • I lost all my files in public folder. (Using a VCS would get your ass saved.)
  • Where are my compiled assets for prod under public/assets directory?
TL, DR - DO NOT name it as any path used by anything else
  • It's being used in:

    • Rails dev server will forward all request under /#{public_output_path} to webpack-dev-server;
    • Webpack will put all compiled assets under public/#{public_output_path}. Unfortunately, it always remove the entire folder before compiling.
  • Alternative ways

    • For dev proxy problem: to set different values for development and production mode in config/vue.yml.
    • For deleting folder when set it to assets for prod: run rake vue:compile[with_rails_assets] to invoke rake compile:assets as well.

Summary

If you still feel confusing, please create a new project and select copy demo code.

I will explain what happens in Explanation by Demo.

Available Settings

General settings file is config/vue.yml

  • entry_path

    Entry point folder. Default: app/assets/vue

  • manifest_output

    Where to put manifest.json which required by Rails production mode. You can set it in development mode for inspection.

    All entry-points will be compiled into assets files. Rails needs manifest.json to know what are the files and will serve all its JS/CSS tags.

  • package_manager

    Pretty straightforward, which package manager will be used. Valid value: npm or yarn. It does NOT support pnpm or other package managers. You can find the reason in Q&A.

  • public_output_path

    Because it is very important I put it in core section.

  • launch_dev_service (NOT available for production mode)

    rails server will launch it when starting by default vue-cli-service serve. It will be invoked by npx vue-cli-service serve or yarn exec vue-cli-service serve depends on your package_manager.

  • camelCase settings will be used in vue.config.js

    Please see available options.

  • alias

    It's basically resolve/alias for Webpack. However, you don't have to config this settings in .eslintrc.js and jest.config.js again and again. @vue/cli will pass the settings to eslint via its plugin. The configuration for jest will be generated and passed to jest.config.js through vue.rails.js.

Customize your webpack configurations in vue.config.js

Feel free to update vue.config.js by yourself. There are some lines of boiler-plate code to adapt compression-webpack-plugin and webpack-bundle-analyzer.

Rake Tasks

  • vue:create

    Install required packages and configurations. You should run this task to get @vue/cli initializing your project.

    What it does for you
    1. Select package manager: Y=yarn, N=npm

      • Directly use npm if yarn has not been installed.
      • Prefer yarn by default unless detect package-lock.json
    2. Auto install @vue/cli globally with your package manager.

    3. Invoke vue create to initialize Vue project.

      When detected existing package.json

      • Y - Yes: Fully overwrite
      • N - No: Skip
      • A - Auto: You won't loss anything (old_config.merge(new_config))
      • K - Keep: Keep all your settings already have (new_config.merge(old_config))
    4. Install js-yaml and webpack-assets-manifest

    5. Deleting Vue demo code under src folder

    6. Copy demo code to under app folder and update config/routes.rb

    7. Copy vue.rails.js and vue.config.js

      • Do not change vue.rails.js! This rake task will always restore vue.rails.js back.
      • Yes you can update vue.config.js. Just make sure you know what are you won't break the configuration. You can chance config/vue.yml instead.
    8. Generate config/vue.yml

      • The convention is: camelCase for regular vue.config.js, snake_case for special usage.
      • You can find a full list of Vue CLI config options below.
      • All available options here

    BE AWARE: the default option for config/vue.yml is Y (to replace existing file), otherwise your package manager change won't be saved. All your files won't be overwritten silently except vue.rails.js.

  • vue:compile

    Compile Vue assets. Please specify RAILS_ENV=production to compile assets for production.

    Optional argument: [with_rails_assets] to invoke rake compile:assets after it finished.

    However, you can invoke vue-cli-service build (if vue-cli-service installed globally, or you can use npx vue-cli-service build or yarn exec vue-cli-service build) with RAILS_ENV=production to build assets.

    A good practice is to use cross-env to pass RAILS_ENV=production. So cross-env RAILS_ENV=production vue-cli-service build will work on any platform and shell.

  • vue:json_config

    Converts config/vue.yml to JSON to be used by vue.rails.js.

    vue.rails.js prefers parsing config/vue.yml with js-yaml. So this is just in case. You may suffer performance issue when your Rails app grow big.

  • vue:support[formats]

    Adds template or style language support. Vue ships with supporting pug, slm, sass, less and stylus out-of-box. How ever, you still have to install some loaders manually if you did not select that language with vue:create.

    You can add multiple languages at the same time: rake vue:support[pug,stylus]

  • vue:node_env

    Adds cross-env and npm-run-all to your devDependencies in package.json, and adds dev, prod, serve and rails-s to scripts as well.

    It enables you to start rails dev server alongside webpack-dev-server without pain, and compile production assets.

    # to start `rails s` and `webpack-dev-server` together
    npm run dev
    # or
    yarn dev
    
    # same as `/usr/bin/env RAILS_ENV=production bundle exec vue:compile`
    npm run prod
    # or
    yarn prod

    You can update scripts/rails-s and/or scripts/prod if you need to more stuff:

    {
      "scripts": {
        "rails-s": "cross-env NO_WEBPACK_DEV_SERVER=1 rails s -b 0.0.0.0",
        "prod": "cross-env RAILS_ENV=production bundle exec rake vue:compile[with_rails_assets]"
      }
    }
  • vue:inspect

    Alias of vue inspect, npx vue-cli-service inspect or yarn exec vue-cli-service inspect. Display the webpack configuration file.

You may need to invoke rake with bundle exec. Rails 5 and above supports new rails rake:task flavor.

Migrate from Webpacker

It's very easy to migrate from Webpacker.

  1. Install this gem and bundle install
  2. Install @vue/cli globally and follow the instructions of rake vue:create;
  3. Edit config/vue.yml, set default/entry_path to source_path (by default app/javascript) joins source_entry_path (by default packs);
  4. Change all javascript_packs_with_chunks_tag to vue_entry;
  5. Fix all nonsense xxxx_packs_tag;
  6. If you mind public_output_path and manifest_output, you can change them to follow Webpacker values;

    I strongly NOT recommend to put manifest_output.json under public folder;

  7. Update vue.config.js if you have any customized webpack configurations;

    You can inspect webpack settings at anytime with rake vue:inspect or vue inspect

  8. Directly rails s to start dev server;

    You can get rid of bin/webpack-dev-server and bin/webpack now. However, still recommend rake vue:node_dev and run yarn dev so it will kill webpack-dev-server properly when your Rails dev server stopped.

  9. Call env RAILS_ENV=production rake vue:compile[with_rails_assets] instead of env RAILS_ENV=production rake assets:precompile to compile all assets for production.
  10. Delete unused Webpacker files
  • bin/webpack-dev-server
  • bin/webpack
  • config/webpack
  • config/webpacker.yml

Strongly recommend to backup your codebase before the migration.

Enjoy Hot Module Replacement now!

Valid Vue CLI config Options

You can check the full list on Vue CLI official website.

  • Special

    • publicPath - see public_output_path

    • outputDir - see public_output_path

    • configureWebpack - vue.rails.js will generate it. entry, output and resolve/alias are heavily required by this gem. So you must manually update it in vue.config.js very carefully.

      Demo

      Changes to vue.config.js

      const {
        manifest,
        pickUpSettings,
        // isProd,
      -  // getSettings,
      +  getSettings,
      } = railsConfig;
      
      + const { configureWebpack: { entry, output, resolve, module: cwModule } } = getSettings('configureWebpack');
      
      module.exports = {
        ...pickUpSettings`
          outputDir
          publicPath
          devServer
      -    configureWebpack
      
          filenameHashing
          lintOnSave
          runtimeCompiler
          transpileDependencies
          productionSourceMap
          crossorigin
          css
          parallel
          pwa
          pluginOptions
        `,
      +  configureWebpack: {
      +    entry,
      +    output,
      +    resolve,
      +    module: cwModule,
      +  },
        chainWebpack: (config) => {
  • Supported

    • filenameHashing
    • lintOnSave
    • runtimeCompiler
    • transpileDependencies
    • productionSourceMap
    • crossorigin
    • css
    • devServer
    • parallel
    • pwa
    • pluginOptions
  • Unsupported

    • baseUrl - Deprecated
    • assetsDir - ignored
    • indexPath - N/A
    • pages - N/A
    • integrity - N/A
    • chainWebpack - directly edit vue.config.js

Trouble Shooting & Known Issues

  • My dev server can't find assets

    Sometimes your webpack-dev-server might still be running while Rails dev server had terminated. For example, you had executed exit! in pry.

    Usually webpack-dev-server should be killed when next time you start rails server. However, for some reason it could fail and the new webpack-dev-server will listen to another port. Then you must manually kill them:

    lsof -i:3080 -sTCP:LISTEN -Pn
    kill -9 <pid>

    Alternatively, you can run rake vue:node_dev and always start your dev server with:

    npm run dev
    # or
    yarn dev

    I know it is not Rails-way at all. I don't want to waste time to reinvent it - you are already using Node, why it bothers you?

  • My API does not work with CSRF token

    Because Vue does not have opinion of Ajax (or JSON API) preference, you must implement what jquery-ujs does by yourself. There is an example in vanilla JS with querySelector (which should work for IE8+) and Fetch API:

    async (url, data) => {
      const $csrfParam = document.querySelector('meta[name="csrf-param"]');
      const $csrfToken = document.querySelector('meta[name="csrf-token"]');
      const csrfParam = ($csrfParam && $csrfParam.getAttribute('content')) || undefined;
      const csrfToken = ($csrfToken && $csrfToken.getAttribute('content')) || undefined;
    
      try {
        const response = await fetch(url, {
          method: 'POST',
          headers: {
            'Content-type': 'application/json',
            'X-CSRF-Token': csrfToken,
          },
          body: JSON.stringify({
            ...data,
            [csrfParam]: csrfToken,
          }),
        });
    
        if (!response.ok) {
          // handle bad response
        }
    
        return response.json();
      } catch (e) {
        // handle failed case
      }
    }

    Alternatively you can turn off CSRF token and set SameSite cookie if all your clients no longer use IE. Modern browsers can handle SameSite flag to prevent CSRF attacks.

  • My Jest complains about import

    Seems transformIgnorePatterns in jest.config.js not working the same way in different environments. I found sometimes <rootDir>/node_modules/ works while /node_modules/ works on another machine. Try to change the order and you will find which one works for you.

  • Mocha tests not working

    This is a known issue and I am not going to fix it recently.

  • TypeScript can not find my aliases

    This is a known issue. TS is still using tsconfig.json rather than a .js or .ts file. You must manually update it for now. I will try to find a way out.

  • My yarn test:.../npm run test:... not working properly

    The test requires setting RAILS_ENV=test. You can invoke rake vue:test[unit] rake vue:test[e2e] instead.

  • Got errors like command "..." does not exist for rake vue:lint/test

    This rake task simply invokes vue-cli-service test:.... Those commands will be generated by some vue plugins. It won't be available unless you got correct plugin installed.

Q & A

Q&A

Can I get rid of js-yaml and webpack-assets-manifest

Only webpack-assets-manifest is a required dependency. It will be used to generate manifest.json which required for both dev and prod.

vue.rails.js uses js-yaml for parsing config/vue.yml. It will fallback to rake vue:json_config if js-yaml not been installed. However, when your Rails app grow bigger, you will very likely find rake tasks start slower and slower.

Can I use HAML for template inside .vue files

Short answer I don't know and I don't recommend. There are several HAML packages but all are too old. JS world suggests pug. You can also use slm if you prefer Slim. Both are quite similar to CSS selector syntax, which means you don't really need to spend time to learn.

Just rake vue:support[pug,slm] and try them out: <template lang="pug"> or <template lang="slm">.

Does it support pnpm

No.

The reason is Vue CLI does not support pnpm very well, or npm does not support @vue/cli. Who knows.

You still have a chance to get it worked by giving pnpm --shamefully-flatten flag, which makes no difference from npm or yarn.

If someday they support each other, I'd like to support pnpm as well.

Your demo code seems awful

Yes I admit it. Personally I'd like to directly write SPA with webpack tooling for front-end. Back-end will be a separated project, and it will be a Rails-API or Sinatra project if I want to use ActiveRecord.

webpack-dev-server can simply be configured with a proxy and I can use something like npm-run-all to start 2 services at the same time. I had to write some not-so-good code to get those things done in Rails.

The demo is more Rails way - separated layouts and views. SPA world uses some client router like vue-router.

It does not work on Windows

Sorry, I don't think many gems work on Windows. Please install a virtual machine and run Linux on it. This gem is very likely working with WSL, however you may suffer performance issues due to its file system

Currently vue.config.js is reading configurations from vue.rails.js which depends on js-yaml. It will fallback to bundle exec rake vue:json_config without js-yaml installed. Your rake tasks may spend a minute to load which apparently is not a good idea.

Will you support SSR

I do want to support SSR. However, the way Vue officially provided requires you to write separated code for client and server then compile with Webpack, which is quite complicated. prerender-spa-plugin might be easier to achieve it.

I will do more investigation like how Nuxt.js does SSR. But I can't guarantee anything now.

Difference from Webpacker

  1. Webpacker is designed more generic. vue_cli-rails is opinionated to just get @vue/cli worked.

  2. Due to the ease of use of @vue/cli this gem is much easier to configure.

  3. This gem does not support .erb files at all

    It does not make any sense to me. What's the benefit? What if someone wants to pass dynamic data in production, which the way erb supposed to work for? Should it launch webpack and spend maybe 10s to compiled it on-the-fly?

    If you want some dynamic data, you should fetch it via some API. That's my opinion and why I don't even think it should have this feature.

  4. This gem only provides 1 helper vue_entry rather than stylesheet_pack_tag, javascript_pack_tag, javascript_packs_with_chunks_tag, image_pack_tag and etc. in Webpacker

    • First of all, JS files are the center of modern front-end world.
    • Modern front-end bundlers like webpack offer lots of fancy features with tools like Babel, TypeScript, eslint and etc. They can take care of all your assets, and always give you correct set of assets.
    • Webpack 4 is even smarter to split common code into chunks.
    • Vue also provides some awesome features like scoped styles, async components.

    All those functionalities are just working out-of-box. You should not even touch them. There is no point of managing assets by yourself. You will eventually shot on your foot:

    • Why my component does not look right? Because you forgot to change your stylesheet_pack_tag after renaming the file.
    • Why my styles from another component aren't working? Because your component uses scoped styles, which designed to only work for that component.
    • Why my component does not work anymore? Because there is a new asset and you never write a _tag for it.

    Trust me, you are not smarter than webpack. This design will save your time.

  5. This gem supports both npm and yarn. Webpacker requires yarn to be installed.

    npm and yarn are not much different nowadays. I myself prefer yarn. But you should be able to use npm which ships with node itself to reduce the complexity of deployment.

    Unfortunately it does not support pnpm

  6. Webpacker ships with plenty of node dependencies in dependencies section rather than devDependencies.

    I'd say this is another thing does not make sense to me. Even there is no real difference for front-end projects, I'd expect a project follows common pattern: the packages will be used in your front-end code should be in dependencies.

  7. productionSourceMap is off by default for production

    You may or may not know Rails turn this flag on by default.

    I just don't buy it. It could be a security issue, especially for a startup or small company where Rails is widely being adapted. There are plenty ways if you intended to open your source, like Gitlab does. You should not do unaware contribution.

    You can manually set productionSourceMap to true in config/vue.yml. Good on you!

  8. This gem puts manifest.json in app/assets/vue directory by default than public.

    Again, I have no idea why Webpacker doing that.

  9. webpack-dev-server automatically starts with rails server in dev mode.

    I don't understand why not to start the killing feature of webpack. Stop wasting your life on stupidly refreshing and waiting the whole page being reloaded while debugging front-end code.

    If your computer is too slow, ask your boss to buy a good one. You deserve it.

  10. Less configurations and easier to understand.

    Only a few platform-specific settings available. All others are very standard.

Explanation by Demo

Copy Demo Code

Install

Run bundle exec rake vue:create or rails vue:create in Rails 5+, and follow the steps:

$ bundle exec rake vue:create
Which package manager to use? (Y=yarn, N=npm) [Yn]
...
? Generate project in current directory? Yes
...
? Check the features needed for your project: Babel, Linter, Unit
? Pick a linter / formatter config: Airbnb
? Pick additional lint features: (Press <space> to select, <a> to toggle all, <i> to invert selection)Lint on save
? Pick a unit testing solution: Jest
? Where do you prefer placing config for Babel, PostCSS, ESLint, etc.? In dedicated config files
...
Do you want to copy demo code? (Y=Yes, N=No) [yN]y
...

First Taste

Now with rails s, open http://localhost:3000/vue_demo/foo in a browser you should be able to see a red big red "Foo" with blue "Hello Vue!".

Do not stop your rails server, open app/assets/vue/views/Foo.vue in your editor:

<template>
  <div id="app">
    <h1>Foo</h1>
-    <HelloWorld msg="Vue!"></HelloWorld>
+    <HelloWorld msg="Rails!"></HelloWorld>
  </div>
</template>

Change msg="Vue!" to msg="Rails!" and save. You will the text in your browser changed to "Hello Rails!". You can change styles or edit app/assets/vue/components/HelloWorld.vue and immediately see the result as well.

This functionality is called HMR (Hot Module Replacement) which is the killing feature provided by webpack-dev-server. You will soon fail in love with this feature and never want to go back to manually refresh your browser again and again.

What in the box

.
├── app
│   ├── assets
│   │   └── vue
│   │       ├── components
│   │       │   ├── HelloWorld.vue
│   │       │   └── layouts
│   │       │       ├── App.vue
│   │       │       └── index.js
│   │       ├── entry_points
│   │       │   ├── bar.js
│   │       │   └── foo.js
│   │       └── views
│   │           ├── Bar.vue
│   │           └── Foo.vue
│   ├── controllers
│   │   └── vue_demo_controller.rb
│   └── views
│       ├── layouts
│       │   └── vue_demo.html.erb
│       └── vue_demo
│           └── foo.html.erb
├── config
│   ├── routes.rb
│   └── vue.yml
├── tests
│   └── unit
│       └── example.spec.js
├── .browserslistrc
├── .editorconfig
├── .eslintrc.js
├── .gitignore
├── babel.config.js
├── jest.config.js
├── package.json
├── postcss.config.js
├── vue.config.js
├── vue.rails.js
└── yarn.lock

You can run ESLint by

$ yarn lint # npm run lint

Run Jest

$ yarn test:unit # npm run test:unit

Compile Assets

First let's compile the assets

$ env RAILS_ENV=production bundle exec rake vue:compile
run: yarn exec vue-cli-service build
...
  File                                      Size             Gzipped

  public/vue_assets/js/chunk-vendors.b54    82.49 KiB        29.80 KiB
  85759.js
  public/vue_assets/js/foo.dcbad15e.js      2.74 KiB         1.23 KiB
  public/vue_assets/js/bar.d4fc59af.js      2.03 KiB         1.00 KiB
  public/vue_assets/css/foo.4bbe6793.css    0.12 KiB         0.11 KiB
  public/vue_assets/css/bar.96de90a8.css    0.02 KiB         0.04 KiB

  Images and other types of assets omitted.
...

Your file names could be different from mine. Don't worry, we won't look those files. There are the files you will get:

.
├── app
│   ├── assets
│   │   └── vue
│   │       └── manifest.json
└── public
    └── vue_assets
        ├── css
        │   ├── bar.96de90a8.css
        │   └── foo.4bbe6793.css
        └── js
            ├── bar.d4fc59af.js
            ├── chunk-vendors.b5485759.js
            └── foo.dcbad15e.js

How Entry Point works

Let's take a look at app/assets/vue/manifest.json:

{
  "bar.css": "/vue_assets/css/bar.96de90a8.css",
  "bar.js": "/vue_assets/js/bar.d4fc59af.js",
  "chunk-vendors.js": "/vue_assets/js/chunk-vendors.b5485759.js",
  "entrypoints": {
    "bar": {
      "js": [
        "/vue_assets/js/chunk-vendors.b5485759.js",
        "/vue_assets/js/bar.d4fc59af.js"
      ],
      "css": [
        "/vue_assets/css/bar.96de90a8.css"
      ]
    },
    "foo": {
      "js": [
        "/vue_assets/js/chunk-vendors.b5485759.js",
        "/vue_assets/js/foo.dcbad15e.js"
      ],
      "css": [
        "/vue_assets/css/foo.4bbe6793.css"
      ]
    }
  },
  "foo.css": "/vue_assets/css/foo.4bbe6793.css",
  "foo.js": "/vue_assets/js/foo.dcbad15e.js"
}

As mentioned above, there are 2 files under app/assets/vue/entry_points folder: foo.js and bar.js. They will become entry points in manifest.json. When you call render vue: 'bar' in VueDemoController or <%= vue_entry('foo') %> in app/views/vue_demo/foo.html.erb, vue_entry will look for them in entrypoints of manifest.json, then generate <link href="<path>" rel="stylesheet"> and <script src="<path>"></script> for each asset.

It's slightly different on dev server. This gem will send requests to webpack-dev-server and fetch the paths on-the-fly. The request will be GET http://localhost:3080/__manifest/?<entry_point> for each vue_entry. You can also send GET request to http://localhost:3080/__manifest/?!!INSPECT!! to get the full manifest.