EBC Exercise 32 gpio via flask

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thumb‎ Embedded Linux Class by Mark A. Yoder

Intro. Much of this is from https://towardsdatascience.com/python-webserver-with-flask-and-raspberry-pi-398423cc6f5d.

Installing Flask

Flask should already be installed on the Bone. But if not:

bone$ sudo apt update
bone$ sudo apt install python3-flask

All the examples are in the class repo

bone$ git clone https://github.com/MarkAYoder/BeagleBoard-exercises.git examples
bone$ cd examples/flash/server

First Flask - hello, world

Our first example is helloWorld.py

#!/usr/bin/env python3
# From: https://towardsdatascience.com/python-webserver-with-flask-and-raspberry-pi-398423cc6f5d

from flask import Flask
app = Flask(__name__)
def index():
    return 'hello, world'
if __name__ == '__main__':
    app.run(debug=True, port=8081, host='')

The first line loads the Flask module into your Python script. The second line creates a Flask object called app. The third line is where the action is, it says to run the index() function when someone accesses the root URL (‘/’) of the server. In this case, only send the text “hello, world” to the client’s web browser thru return.

The last line says to “listen” on port 8081, reporting any errors.

thumb‎ Embedded Linux Class by Mark A. Yoder