ruby-on-rails - React Rails 与 Webpacker 不热重载

Question

我已将 react-rails 添加到我们正在慢慢迁移到 React 的现有项目中。

当前的 webpacker.yml

default: &default
  source_path: app/javascript
  source_entry_path: packs
  public_output_path: packs
  cache_path: tmp/cache/webpacker

  # 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

  extensions:
    - .jsx
    - .js
    - .sass
    - .scss
    - .css
    - .module.sass
    - .module.scss
    - .module.css
    - .png
    - .svg
    - .gif
    - .jpeg
    - .jpg
    - .tsx
    - .ts

development:
  <<: *default
  compile: true

  # Reference: https://webpack.js.org/configuration/dev-server/
  dev_server:
    https: false
    host: localhost
    port: 3035
    public: localhost:3035
    hmr: true
    # 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/

我在一个终端中启动 Rails 应用程序，在另一个终端中启动 ./bin/webpack-dev-server，我可以看到编译中出现的热门模块:

[./node_modules/webpack-dev-server/client/index.js?http://localhost:3035] (webpack)-dev-server/client?http://localhost:3035 7.93 kB {0} {1} [built]
[./node_modules/webpack-dev-server/client/overlay.js] (webpack)-dev-server/client/overlay.js 3.67 kB {0} {1} [built]
[./node_modules/webpack/hot/dev-server.js] (webpack)/hot/dev-server.js 1.61 kB {0} {1} [built]
[./node_modules/webpack/hot/emitter.js] (webpack)/hot/emitter.js 77 bytes {0} {1} [built]
[./node_modules/webpack/hot/log-apply-result.js] (webpack)/hot/log-apply-result.js 1.31 kB {0} {1} [built]
[./node_modules/webpack/hot/log.js] (webpack)/hot/log.js 1.04 kB {0} {1} [built]
   [0] multi (webpack)-dev-server/client?http://localhost:3035 webpack/hot/dev-server ./app/javascript/packs/application.js 52 bytes {1} [built]
   [1] multi (webpack)-dev-server/client?http://localhost:3035 webpack/hot/dev-server ./app/javascript/packs/server_rendering.js 52 bytes {0} [built]

问题是当我运行 ./bin/webpack-dev-server 时，每次更新 react 文件(而不是刚刚更新的组件)时，我都会刷新整个页面。全页面刷新仅在开发服务器运行时发生。另外，在整个页面刷新之前，我没有看到组件更新。

所以问题是，为什么 webpack-dev-server 发出浏览器页面刷新信号以及为什么组件不热重载？

Answer 1

这就是 Webpack HMR 的工作原理，如果你想在你的 React 模块上启用 HMR，你可以尝试 React Hot Loader与 Webpack plugin

。使用 yarn 安装 react-hot-loader

。编辑 .babelrc 文件并将 react-hot-loader/babel 添加到插件列表中。

。让你的 React 组件“热”。

import React from 'react'
import { hot } from 'react-hot-loader'

class Example extends React.Component {
}

export default hot(module)(Example);