HMR in asp.net core with React - asp.net

Question

I started my project using .net core cli.
dotnet new react -o my app
and for development, I changed my env var
export ASPNETCORE_Environment=Development
I am not very comfortable with Typescript so, I prefer use .jsx files and babel, so I decided to change my webpack.config.js. In module rules, I added:
const BABEL_LOADER_PLUGINS = [
require.resolve("babel-plugin-transform-class-properties"),
require.resolve("babel-plugin-transform-object-rest-spread"),
require.resolve("babel-plugin-transform-regenerator")
];
/*...webpack config code ... */
{
test: /\.jsx$/,
exclude: /node_modules/,
use: [
{
loader: "babel-loader",
options: {
presets: ["env", "react"],
plugins: BABEL_LOADER_PLUGINS
}
}
]
}
I did my new components with .jsx extensions and it works. So my next step is to do HMR work.
In my Startup.cs:
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
app.UseWebpackDevMiddleware(new WebpackDevMiddlewareOptions
{
HotModuleReplacement = true
});
}
In client at root component, using react-hot-loader':
let HotApp;
if (__CONFIGS__.isDevServer) {
const { hot } = require('react-hot-loader');
HotApp = hot(module)(App);
} else {
HotApp = App;
}
const Root = (
<Provider store={store}>
<BrowserRouter>
<HotApp />
</BrowserRouter>
</Provider>
);
hydrate(Root, document.getElementById('react-app'));
And this sometimes works. In the console, I can see [HMR] connected and updates. If I stop the process, it is possible that console shows [HMR] connected but if I do some changes in a component nothing happens. I don't know why sometimes works well.

Answer 1

We can use Create React App Configuration Override (#craco/craco) along with craco-plugin-react-hot-reload CRACO plugin to add HMR without ejecting the CRA application.
Install #craco/craco by following the installation guide
Install craco-plugin-react-hot-reload
npm i -D craco-plugin-react-hot-reload
Add craco-plugin-react-hot-reload into craco.config.js
const reactHotReloadPlugin = require('craco-plugin-react-hot-reload');
module.exports = {
plugins: [{
plugin: reactHotReloadPlugin
}],
webpack: [...]
}
Install #hot-loader/react-dom
npm i #hot-loader/react-dom
Mark your App component as hot-exported (into ClientApp\src\App.js)
import { hot } from 'react-hot-loader/root';
function App() {...}
export default hot(App);
Now HMR will work properly when we start the project using dotnet run.
Tested (on May 2020) using React 16.13.1. We must use the same major and minor versions for react, react-dom and #hot-loader/react-dom (16.13.x).