Question

使用Ruby on Rails Webpacker在视图中包含图像时出现问题。当我尝试使用html img标签和asset_pack_path在视图中插入图像时，出现错误。我的图像位于app/javascript/images/logo.png中。根据webpacker docs，我应该将/ media /附加到文件中，但这无济于事。我尝试了不同的路径，但仍然无法正常工作。我认为webpacker无法编译我的映像。

Webpacker::Manifest::MissingEntryError in Home#index
Showing app/views/layouts/application.html.haml where line #14 raised:

Webpacker can't find media/logo.png in public/packs/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:
{
  "application.js": "/packs/js/application-321d1c3bcc175b7f61a6.js",
  "application.js.map": "/packs/js/application-321d1c3bcc175b7f61a6.js.map",
  "entrypoints": {
    "application": {
      "js": [
        "/packs/js/application-321d1c3bcc175b7f61a6.js"
      ],
      "js.map": [
        "/packs/js/application-321d1c3bcc175b7f61a6.js.map"
      ]
    },
    "hello_react": {
      "js": [
        "/packs/js/hello_react-c48c89eaf873362b846b.js"
      ],
      "js.map": [
        "/packs/js/hello_react-c48c89eaf873362b846b.js.map"
      ]
    }
  },
  "hello_react.js": "/packs/js/hello_react-c48c89eaf873362b846b.js",
  "hello_react.js.map": "/packs/js/hello_react-c48c89eaf873362b846b.js.map"
}

我认为application.html.haml

!!! 5
%html
  %head
   = javascript_pack_tag 'application', 'data-turbolinks-track': 'reload'
    = stylesheet_pack_tag    'application'
  %body
    %nav.navbar.navbar-expand-lg.navbar-light.bg-primary
      %a.navbar-brand(href="/")
        %img(src="#{asset_pack_path 'media/logo.png'}")

app/javascript/packs/application.js

require.context('../images', true)

import 'bootstrap'
import './src/application.scss'

Procfile.dev

web: bundle exec rails s
webpacker: ./bin/webpack-dev-server

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: []

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

development:
  <<: *default
  compile: true

  # Verifies that versions and hashed value of the package contents in the project's package.json
  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: false

  # Extract and emit a css file
  extract_css: true

  # Cache manifest.json for performance
  cache_manifest: true

Answer 1

我在使图像显示在Rails 6中时遇到问题。我做到了：

将图像添加到

assets/custom_folder/img_filename.file_extension

取消注释javascript / packs / application.js中的两行

const images = require.context('../images', true)
const imagePath = (name) => images(name, true)

然后使用以下方法将图像添加到erb文件中：（我有一个index.html.erb视图文件）

<%= image_tag("custom_folder/file_name.file_extension")%>

这对我有用，希望对您有所帮助。

签出this link

Answer 2

我的图片位于/app/assets/images中。

首先将app/assets添加到resolved_paths: ['app/assets']中的webpacker.yml

然后您可以在JS中使用该法师：

<img src='~images/logo.png' />

在CSS中：

<style lang='sass'>
#app
  background: url('~images/logo.png')
</style>

Answer 3

该路径似乎不在清单文件中。

在Rails 6中，application.js中有两条注释行。无论您运行的是哪个Rails版本，都请确保将它们添加到以下位置：

const images = require.context('../images', true)
const imagePath = (name) => images(name, true)

或者，您可以通过在packs中移动文件夹来强制将图像添加到清单中。 packs/images。路径将更改为media/images/your-file.png。

为了查看路径是否存在，我发现直接从ruby中查找路径更容易：

Webpacker.manifest.send(:data).keys.grep /logo/

Answer 4

将图像放入 app/javascripts/images
将以下代码放入 application.js 中，位于文件的顶部。

// top of packs/application.js

const importAll = (r) => r.keys().map(r)

importAll(require.context('../images', false, /\.(png|jpe?g|svg)$/));
这将从图像文件夹中加载所有图像，然后它应可用于清单中，以供您使用 asset_pack_path
在您的erb文件中，使用类似<%= asset_pack_path 'media/images/image_name.png' %>

-详细了解https://github.com/rails/webpacker/issues/1839

Answer 5

要访问由 Sprockets 处理的图像，请将其添加到 your_file_name.js.erb 文件中：

<% helpers = ActionController::Base.helpers %>
const railsImagePath = "<%= helpers.image_path('your_image.png') %>"

Ruby on Rails Webpacker在asset_pack_path

5 个答案: