Focusing on a development workflow, as there are countless choices in how to deploy to a production environment.
Run your Flask app with /api as the root url prefix, either manually by prefixing all your route decorators or with the use of a Blueprint.
py/app.py
@app.route('/api')
def index():
return {'message':'hello'}
Add the Flask development server url to your package.json file
js/package.json
{
...,
"proxy": "http://localhost:5000"
}
Fetch your data using a component
js/Flask.js
import React, { Component } from 'react'
export class Flask extends Component {
constructor(props) {
super(props)
this.state = { data: {}, status: null }
}
fetchData() {
let status
fetch('/api')
.then((res) => {
return {
data: res.json(),
status: status
}
})
.then((data) => {
this.setState({ ...data })
}
.catch((err) => {
console.error(err)
})
}
componentDidMount() {
this.fetchData()
}
render() {
const { data, status } = this.state
return (
<div>
<h3>Status: { status }</h3>
<pre>
{ JSON.stringify(data) }
</pre>
</div>
)
}
}
export default Flask
Finally, include the component in your main App
js/App.js
import React from 'react';
import Flask from './Flask'
function App() {
return (
<div className="App">
<Flask />
</div>
);
}
export default App;
Start your Flask server with your preferred method, either flask run or by executing your script directly, then start your JS development server with either yarn or npm start. You should see the response from your api route displayed at http://localhost:8000
As long as you are running your Flask server with debug=True and use npm start (not npm run build), any changes made with either the backend or frontend will be automatically detected and your app reloaded.
