debug mode flask code example

Example 1: flask debug

$ export FLASK_ENV=development
$ flask run

Example 2: flask how to run app

$ export FLASK_APP=hello.py
$ python -m flask run
 * Running on http://127.0.0.1:5000/

Example 3: how to set debug mode on in flask

set "FLASK_DEBUG=1" in .flaskenv file of your project.

Example 4: default flask app

from flask import Flask
app = Flask(__name__)

@app.route('/')
def index():
    return 'Flask'