javascript - Rails : Webpacker 4. 2 在/app/public/packs/manifest.json heroku 中找不到应用程序

Question

我有点难过。我的本地 Rails 应用程序与 webpacker 4.2 配合得很好并且有反应，但是当部署到生产环境时，出现了美妙的无法在/app/public/packs/manifest.json 中找到应用程序 错误。

这是我尝试过的:

• 尝试为 javascript 包标签添加/删除 turbo 链接详细信息。
• 删除了 javascript 包含标记(不确定这是否有帮助)
• 确保我使用的是最新的 webpacker 4.2
• 在 heroku 上手动运行 rake assets:clean && rake assets:precompile 以确保构建成功。

我是否遗漏了构建步骤或生产中会导致此问题的某些内容？还需要检查什么？

服务器错误:

2019-12-03T15:18:19.022024+00:00 app[web.1]: I, [2019-12-03T15:18:19.021952 #30]  INFO -- : [aa0374eb-bab1-40cc-b40b-6ae3d195e07d] Completed 500 Internal Server Error in 112ms (ActiveRecord: 30.4ms | Allocations: 21296)
2019-12-03T15:18:19.023103+00:00 app[web.1]: F, [2019-12-03T15:18:19.023029 #30] FATAL -- : [aa0374eb-bab1-40cc-b40b-6ae3d195e07d]
2019-12-03T15:18:19.023107+00:00 app[web.1]: [aa0374eb-bab1-40cc-b40b-6ae3d195e07d] ActionView::Template::Error (Webpacker can't find application in /app/public/packs/manifest.json. Possible causes:
2019-12-03T15:18:19.023109+00:00 app[web.1]: 1. You want to set webpacker.yml value of compile to true for your environment
2019-12-03T15:18:19.023111+00:00 app[web.1]: unless you are using the `webpack -w` or the webpack-dev-server.
2019-12-03T15:18:19.023114+00:00 app[web.1]: 2. webpack has not yet re-run to reflect updates.
2019-12-03T15:18:19.023116+00:00 app[web.1]: 3. You have misconfigured Webpacker's config/webpacker.yml file.
2019-12-03T15:18:19.023118+00:00 app[web.1]: 4. Your webpack configuration is not creating a manifest.
2019-12-03T15:18:19.023120+00:00 app[web.1]: Your manifest contains:

{
 "application.js": "/packs/js/application-2a0e2c932678ebbf2ae7.js",
"application.js.map": "/packs/js/application-2a0e2c932678ebbf2ae7.js.map",
"entrypoints": {
 "application": {
"js": [
"/packs/js/application-2a0e2c932678ebbf2ae7.js"
],
 "js.map": [
 "/packs/js/application-2a0e2c932678ebbf2ae7.js.map"
 ]
 },
 "server_rendering": {
 "js": [
 "/packs/js/server_rendering-eb794d024d4852e8ab55.js"
],
 "js.map": [
 "/packs/js/server_rendering-eb794d024d4852e8ab55.js.map"
 ]
}
 },
"server_rendering.js": "/packs/js/server_rendering-eb794d024d4852e8ab55.js",
"server_rendering.js.map": "/packs/js/server_rendering-eb794d024d4852e8ab55.js.map"
}

...

<%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track': 'reload' %>
<%= stylesheet_pack_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
<%= javascript_pack_tag 'application' %>

<link href="https://fonts.googleapis.com/css?family=Open+Sans|Roboto+Slab:700&display=swap" rel="stylesheet">

2019-12-03T15:18:19.023193+00:00 app[web.1]: [aa0374eb-bab1-40cc-b40b-6ae3d195e07d] app/views/layouts/application.html.erb:10

Webpacker.yml

    # 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
      check_yarn_integrity: false
      webpack_compile_output: false

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

      # 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:
        - .jsx
        - .vue
        - .mjs
        - .js
        - .sass
        - .scss
        - .css
        - .module.sass
        - .module.scss
        - .module.css
        - .png
        - .svg
        - .gif
        - .jpeg
        - .jpg

    development:
      <<: *default
      compile: true

      # Verifies that correct packages and versions are installed by inspecting package.json, yarn.lock, and node_modules
      check_yarn_integrity: 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
        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

    production:
      <<: *default

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

      # Extract and emit a css file
      extract_css: true

      # Cache manifest.json for performance
      cache_manifest: true

Answer 1

好像没有application.css在你的manifest.json这意味着您可能不会从 Webpack javascript 文件中导入任何 css。

如果这一切都是真的，那么您可以通过以下方式之一修复生产中的错误:

• 快速(临时)修复:添加 extract_css: false给你的production阻止 config/webpacker.yml (这将模仿您本地的环境)
• 如果你不想用 Webpacker 编译 css:删除 <%= stylesheet_pack_tag 'application' %>从您的应用布局
• 如果你想用 Webpacker 编译一些 css:从你的 Webpack javascript 导入至少一个 css 文件