express hot-reload

expressJS hot update problem, I checked a lot of information, the method is similar, I use nodemon, but the service cannot be started

Later reference: ​ ​Automatically refresh the browser on Node / Express server changes 🚀 - DEV Community​​

It is not possible to use nodemon app.js

It is also recommended to use yarn to start: yarn watch can be used

**Installation

npm install -g yarn

npm install -g nodemon