Running background tasks when streaming
Our image service works but has a significant flaw. Currently it will wait between requests before taking each action, but what if we want our robot to be doing something? To do this, we need to be able to run a behavior in parallel with the server. That behavior and the server both need access to the image data.
We will approach this by making the Flask web app a secondary process, with the behavior as the primary process for the robot when it is running. Python has a handy tool for precisely this kind of structure, called multiprocessing. Find out more at https://docs.python.org/3/library/multiprocessing.html.
Communicating between multiple processes is tricky. If two processes try to access (read or write) the same data simultaneously, the results can be unpredictable and cause strange behavior. So, to save them trying to access data simultaneously, we will use the multiprocessing queue object. A queue allows one process to put data...
