Serving a web page

Similarly to the RESTful API example, we configure the core Flask framework to serve a web page from the root URL using the @app.route() decorator:

@app.route('/', methods=['GET'])
def index():
    """Make sure index_web_sockets.html is in the templates folder
    relative to this Python file."""
    return render_template('index_web_sockets.html',         # (3)
                           pin=LED_GPIO_PIN)          

For our Web Socket server, this time, we are serving the HTML file, index_web_sockets.html, which we will be covering shortly in the next section, Adding a Web Socket client web page.

Next, we start to see the code that sets up and handles Web Socket event messages.