flask hello world

In this tutorial you’ll learn how to build a web app with Python.

We’ll use a micro-framework called Flask. It has a small core but is extensible with many plugins such as SQLAlchemy, Babel, CouchDB, MongoDB etc.

Some Flask example apps are:

• flaskr — a microblog
• minitwit — a twitter clone
• flask website — static pages + mailinglist archives

Related course
Python Flask: Make Web Apps with Python

• easy to use.
• built in development server and debugger
• integrated unit testing support
• RESTful request dispatching
• uses Jinja2 templating
• support for secure cookies (client side sessions)
• 100% WSGI 1.0 compliant
• Unicode based
• extensively documented

Download Flask Examples

Installing Flask

Install Flask using the command below:

pip install Flask

Flask hello world app

Create a file called hello.py

from flask import Flask
app = Flask(__name__)

@app.route("/")
    def hello():
        return "Hello World!"

if __name__ == "__main__":
    app.run()

Finally run the web app using this command:

$ python hello.py
* Running on http://localhost:5000/

Open http://localhost:5000/ in your webbrowser, and “Hello World!” should appear.

Download Flask Examples

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