Functional Web Development with Elixir, OTP, and Phoenix

Initializing GenServer State

Until now, we’ve relied directly on GenServer’s built-in start_link/3 function for starting new processes. This works, but we can do better.

When we run GenServer.start_link(Game, <initial state>), the idea that we’re starting a new game process is buried in the arguments. It would be much clearer if we could bring the Game module out front by writing Game.start_link(<initial state>).

To do this, we’ll follow the GenServer pattern—define a public function that wraps a GenServer module function that triggers a callback.

Let’s start with a public start_link/1 function in the Game module and have it wrap the GenServer.start_link/3 function. One player will start the game, and the second will join later. Let’s have ...