Rate limit game creation

config/config.exs

@@ -12,7 +12,9 @@ config :chessh, RateLimits,
   max_concurrent_user_sessions: 5,
   player_session_message_burst_ms: 500,
   player_session_message_burst_rate: 8,
-  player_public_keys: 15
+  player_public_keys: 15,
+  create_game_ms: 60 * 1000,
+  create_game_rate: 2
 
 config :chessh, Web,
   github_oauth_login_url: "https://github.com/login/oauth/access_token",

lib/chessh/ssh/client/client.ex

@@ -45,9 +45,8 @@ defmodule Chessh.SSH.Client do
           screen_state_initials: screen_state_initials
         } = state
       ) do
-    {:ok, new_screen_pid} =
-      GenServer.start_link(module, [%{screen_state_initial | client_pid: self()}])
-
+    case GenServer.start_link(module, [%{screen_state_initial | client_pid: self()}]) do
+      {:ok, new_screen_pid} ->
         send(new_screen_pid, {:render, width, height})
 
         {:noreply,
@@ -56,6 +55,10 @@ defmodule Chessh.SSH.Client do
            | screen_pid: new_screen_pid,
              screen_state_initials: [{module, screen_state_initial} | screen_state_initials]
          }}
+
+      _ ->
+        {:noreply, state}
+    end
   end
 
   @impl true

lib/chessh/ssh/client/game/game.ex

@@ -59,9 +59,23 @@ defmodule Chessh.SSH.Client.Game do
   end
 
   def init([
-        %State{player_session: player_session, color: color, game: nil} = state
+        %State{player_session: player_session, color: color, game: nil, client_pid: client_pid} =
+          state
         | tail
       ]) do
+    [create_game_ms, create_game_rate] =
+      Application.get_env(:chessh, RateLimits)
+      |> Keyword.take([:create_game_ms, :create_game_rate])
+      |> Keyword.values()
+
+    case Hammer.check_rate_inc(
+           :redis,
+           "player-#{state.player_session.id}-create-game-rate",
+           create_game_ms,
+           create_game_rate,
+           1
+         ) do
+      {:allow, _count} ->
         # Starting a new game
         {:ok, %Game{} = game} =
           Game.changeset(
@@ -85,6 +99,19 @@ defmodule Chessh.SSH.Client.Game do
           }
           | tail
         ])
+
+      {:deny, _limit} ->
+        send(
+          client_pid,
+          {:send_to_ssh,
+           [
+             Utils.clear_codes(),
+             "You are creating too many games, and have been rate limited. Try again later.\n"
+           ]}
+        )
+
+        {:stop, :normal, state}
+    end
   end
 
   def init([