In this tutorial, we are going to see a very basic app that will allow to send messages between the server using Flask and an Angular. My goal is to send messages from the server to the client to keep the data updated on the client-side using WebSockets.
One of the advantages of using WebSockets is that a single connection is used between the server and the client and either the server or the client can send data to each other. In my case a need to send data from my sensor (that is connected to my server) to the angular client to keep the values updated.
David Mata blog 