Code a simple app In Flask
How To code a simple Flask Application
This page explains how to code a simple Flask application.
- Basic programming knowledge in Python
- Basic Flask knowledge
- Comfortable using a terminal
✅ A minimal app
Before using Flask, we need to install it. Open a terminal and type:
$ pip install Flask
Create a new file hello.py with the following content:
from flask import Flask
app = Flask(__name__)
return f'Hello from Flask!'
Once the file is saved, let's start the app:
$ # Set up the DEBUG environment
$ # (Unix/Mac) export FLASK_ENV=development
$ # (Windows) set FLASK_ENV=development
$ # (Powershell) $env:FLASK_ENV = "development"
$ flask run
$ # Visit the app in browser: http://127.0.0.1:5000/
By visiting the app in the browser we should see "Hello from Flask" message.