This is a WebSocket server that transforms the controlling data from the web client to operate the cash launcher from Raspberry Pi.
It uses the ws library to accept WebSocket connections from the client. It
has 2 endpoints: /orientation and /velocity. It transforms the device
orientation and swiping velocity sent from the client to PWM signals and
enabling signals, which are used to control the 2 servos and 1 motor connected
to Raspberry Pi. The low-level GPIO operations are handled by the rpio
package. rxjs is also used to help with the data transformation.
The server is secured using HTTPS, so a pair of key and certifications files
namely key.pem and crt.pem need to be put under the project root before
running the server.
The server also provides an HTTP endpoint /siri. When called. it makes the
motor on the cash launcher to work for 500ms.