ruby-on-rails - CIに存在しないmanifest.jsonへの適切なRailsソリューション

Question

私のテストが CI、具体的には Heroku で実行されると、次のエラーが発生します。

Webpacker can't find application.js in /app/public/packs-test/manifest.json. Possible causes

これは、フロントエンドのアセットがコンパイルされていないためだと思います。それを解決する正しいRailsの方法は何ですか?

たとえば、追加すると

"test-setup": "bundle exec rake webpacker:compile",

Heroku 用の私のスクリプトでは動作しますが、これは回避策のように感じられ、適切な解決策ではありません。適切な解決策は、Rails がテストの実行時にアセットを自動的にコンパイルするようにすることですよね? CI構成に依存しないもの。

完全なエラーは次のとおりです。

  1) /friendships when logged in gets a list of friends
     Failure/Error: <%= javascript_pack_tag "application", "data-turbolinks-track": "reload" %>
     ActionView::Template::Error:
       Webpacker can't find application.js in /app/public/packs-test/manifest.json. Possible causes:
       1. You want to set webpacker.yml value of compile to true for your environment
          unless you are using the `webpack -w` or the webpack-dev-server.
       2. webpack has not yet re-run to reflect updates.
       3. You have misconfigured Webpacker's config/webpacker.yml file.
       4. Your webpack configuration is not creating a manifest.
       Your manifest contains:
       {
       }
     # ./app/views/layouts/application.html.erb:30:in `_app_views_layouts_application_html_erb___487359012740265845_49820'
     # ./spec/requests/friendships_spec.rb:34:in `block (3 levels) in <top (required)>'
     # ------------------
     # --- Caused by: ---
     # Webpacker::Manifest::MissingEntryError:
     #   Webpacker can't find application.js in /app/public/packs-test/manifest.json. Possible causes:
     #   1. You want to set webpacker.yml value of compile to true for your environment
     #      unless you are using the `webpack -w` or the webpack-dev-server.
     #   2. webpack has not yet re-run to reflect updates.
     #   3. You have misconfigured Webpacker's config/webpacker.yml file.
     #   4. Your webpack configuration is not creating a manifest.
     #   Your manifest contains:
     #   {
     #   }
     #   ./app/views/layouts/application.html.erb:30:in `_app_views_layouts_application_html_erb___487359012740265845_49820'

Webpacker はテストモードでコンパイルするように設定されています (デフォルト):

# Note: You must restart bin/webpack-dev-server for changes to take effect

default: &default
  source_path: app/javascript
  source_entry_path: packs
  public_root_path: public
  public_output_path: packs
  cache_path: tmp/cache/webpacker
  webpack_compile_output: true

  # Additional paths webpack should lookup modules
  # ['app/assets', 'engine/foo/app/assets']
  additional_paths: [ ]

  # Reload manifest.json on all requests so we reload latest compiled packs
  cache_manifest: false

  # Extract and emit a css file
  extract_css: false

  static_assets_extensions:
    - .jpg
    - .jpeg
    - .png
    - .gif
    - .tiff
    - .ico
    - .svg
    - .eot
    - .otf
    - .ttf
    - .woff
    - .woff2

  extensions:
    - .mjs
    - .js
    - .sass
    - .scss
    - .css
    - .module.sass
    - .module.scss
    - .module.css
    - .png
    - .svg
    - .gif
    - .jpeg
    - .jpg

development:
  <<: *default
  compile: true

  # Reference: https://webpack.js.org/configuration/dev-server/
  dev_server:
    https: false
    host: localhost
    port: 3035
    public: localhost:3035
    hmr: false
    # Inline should be set to true if using HMR
    inline: true
    overlay: true
    compress: true
    disable_host_check: true
    use_local_ip: false
    quiet: false
    pretty: false
    headers:
      'Access-Control-Allow-Origin': '*'
    watch_options:
      ignored: '**/node_modules/**'

test:
  <<: *default
  compile: true

  # Compile test packs to a separate directory
  public_output_path: packs-test

staging:
  <<: *default

  # Staging depends on precompilation of packs prior to booting for performance.
  compile: false

  # Extract and emit a css file
  extract_css: true

  # Cache manifest.json for performance
  cache_manifest: true

production:
  <<: *default

  # Production depends on precompilation of packs prior to booting for performance.
  compile: false

  # Extract and emit a css file
  extract_css: true

  # Cache manifest.json for performance
  cache_manifest: true