GenServer.Proxy behaviour (GenServer Proxy v0.1.33) View Source

Invokes call, cast or stop in GenServer with a registered server name. Will wait a bit if the server name is not yet registered on restarts.

Link to this section Summary

Functions

__using__(options)

Either aliases GenServer.Proxy (this module) and requires the alias or imports GenServer.Proxy. In the latter case, you could instead simply import GenServer.Proxy.

call(request, server_id, module \\ nil)

Makes a synchronous call to the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

cast(request, server_id, module \\ nil)

Sends an async request to the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

stop(reason, server_id, module \\ nil)

Synchronously stops the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

Callbacks

server_name(server_id)

Converts server_id into a server name like a via tuple.

server_unregistered(server_id)

Called when the server remains unregistered despite waiting a bit.

Link to this section Functions

using(options)

(macro)

Either aliases GenServer.Proxy (this module) and requires the alias or imports GenServer.Proxy. In the latter case, you could instead simply import GenServer.Proxy.

Examples

use GenServer.Proxy, alias: Proxy

use GenServer.Proxy

import GenServer.Proxy

call(request, server_id, module \\ nil)

(macro)

Makes a synchronous call to the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

The given module (or by default <caller's_module>.GenServerProxy) must implement the 2 callbacks of GenServer.Proxy (this module).

Examples

# Assuming the following callback module:

defmodule Game.Engine.GenServerProxy do
  @behaviour GenServer.Proxy

  @impl GenServer.Proxy
  def server_name(game_name),
    do: {:via, Registry, {:registry, game_name}}

  @impl GenServer.Proxy
  def server_unregistered(game_name),
    do: IO.puts("Game #{game_name} not started.")
end

# We could use the call macro like so:

defmodule Game.Engine do
  use GenServer.Proxy

  def summary(game_name), do: call(:summary, game_name)
  ...
end

cast(request, server_id, module \\ nil)

(macro)

Sends an async request to the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

The given module (or by default <caller's_module>.GenServerProxy) must implement the 2 callbacks of GenServer.Proxy (this module).

stop(reason, server_id, module \\ nil)

(macro)

Synchronously stops the server registered via server_id. Will wait a bit if the server is not yet registered on restarts.

The given module (or by default <caller's_module>.GenServerProxy) must implement the 2 callbacks of GenServer.Proxy (this module).

Link to this section Callbacks

server_name(server_id)

Specs

server_name(server_id :: term()) :: GenServer.name()

Converts server_id into a server name like a via tuple.

Examples

@impl GenServer.Proxy
def server_name(game_name),
  do: {:via, Registry, {:registry, game_name}}

@impl GenServer.Proxy
def server_name(game_name),
  do: {:global, {GameServer, game_name}}

server_unregistered(server_id)

Specs

server_unregistered(server_id :: term()) :: term()

Called when the server remains unregistered despite waiting a bit.

Examples

@impl GenServer.Proxy
def server_unregistered(game_name),
  do: IO.puts("Game #{game_name} not started.")