I'm new to software development in general, and I'm writing a backend for a simple ride-sharing iOS application (which I'll develop later). I'm using Vapor to create the backend.
When a user makes a trip request to the API, I want to create a new trip and establish a websocket session between the user and a driver. The problem I'm having is how can I notify a driver that a request is in and add him to the session?
Here's what I've come up with so far, although I'm not sure if it's going to work:
When a trip request comes in, I would create a session and a trip object with the session id. When a driver visits the "Trip requests" tab in the app he would make a get request to retrieve active trip requests. When he then clicks on one of the trip requests, he would make a request with the session id of that particular trip to be added to that session.
The problems I'm seeing with the above solution is that that would make the User the Poster, and the Driver the Observer, which I'm not sure is the way to go since I want the driver to act as a poster (to send location updates so that the user can track the driver on the map in real time).
Another problem is that users would have to wait indefinitely before a driver accepts their request.
Is there a better way to notify the driver of a trip request? How can I go about achieving this?
First, you will get trouble when trying to establish a direct connection between user and driver, because it's quite difficult to directly connect to an app on a smartphone (changing IPs, NAT, firewalls and opening ports are some of the problems).
I'd suggest, you implement some kind of REST API for the trips/trip requests. To notify the driver or send updates back to the user, you can either use push notifications (for iOS it's APNS) or websockets. In the best case both for different situations.
Here are some hints for further research on those topics:
I hope that helps for your next steps. Your question is quite broad to be more specific.