refactoring of modules

lib/metrics.ex

@@ -1,101 +1,14 @@
 defmodule PlantIdDiscordBot.Metrics do
-  use Agent
-  alias PlantIdDiscordBot.Metrics
+  alias PlantIdDiscordBot.Metrics.Requests
 
-  @file_path "priv/metrics"
-
-  defstruct [
-    :guild_id,
-    :guild_name,
-    :first_request_at,
-    :last_request_at,
-    :total_requests
-  ]
-
-  def start_link(_opts) do
-    initial_state =
-      case File.exists?(Path.join(@file_path, "requests")) do
-        true -> read()
-        false -> %{}
-      end
-
-    Agent.start_link(fn -> initial_state end, name: via_tuple(:metrics))
+  def backup() do
+    Requests.write()
   end
 
-  defp via_tuple(key) do
-    PlantIdDiscordBot.ProcessRegistry.via_tuple({__MODULE__, key})
+  def increase_request_count(guild_id, guild_name) do
+    Requests.put(guild_id, guild_name)
   end
 
-  defp get_pid do
-    [{pid, _value}] = Registry.lookup(PlantIdDiscordBot.ProcessRegistry, {__MODULE__, :metrics})
-    pid
-  end
-
-  def get(key) do
-    get_pid()
-    |> Agent.get(&Map.get(&1, key))
-  end
-
-  def get_all() do
-    get_pid()
-    |> Agent.get(& &1)
-  end
-
-  def put(guild_id, guild_name) do
-    get_pid()
-    |> Agent.update(fn state ->
-      case Map.get(state, guild_id) do
-        nil ->
-          Map.put(state, guild_id, %Metrics{
-            guild_id: guild_id,
-            guild_name: guild_name,
-            first_request_at: DateTime.utc_now(),
-            last_request_at: DateTime.utc_now(),
-            total_requests: 1
-          })
-
-        existing ->
-          Map.put(state, guild_id, %Metrics{
-            existing
-            | last_request_at: DateTime.utc_now(),
-              total_requests: existing.total_requests + 1
-          })
-      end
-    end)
-  end
-
-  @doc """
-  Reset metrics state and remove the saved file from disk.
-  """
-  def reset() do
-    get_pid()
-    |> Agent.update(fn _ -> %{} end)
-
-    file = Path.join(@file_path, "requests")
-
-    if File.exists?(file) do
-      File.rm!(Path.join(@file_path, "requests"))
-    end
-  end
-
-  @doc """
-  Write the current state to disk. To be consumed by a CRON job.
-  """
-  def write() do
-    File.mkdir_p!("priv/metrics")
-
-    data =
-      get_all()
-      |> :erlang.term_to_binary()
-
-    File.write!(Path.join(@file_path, "requests"), data)
-  end
-
-  @doc """
-  Read the state from disk. To be loaded into state on process start.
-  """
-  def read() do
-    File.read!(Path.join(@file_path, "requests"))
-    |> :erlang.binary_to_term()
-  end
+  def requests(guild_id), do: Requests.get(guild_id)
+  def requests(), do: Requests.get_all()
 end