git.squeep.com Git - akkoma/blob - lib/healthcheck.ex

   1 defmodule Pleroma.Healthcheck do
   2   @moduledoc """
   3   Module collects metrics about app and assign healthy status.
   4   """
   5   alias Pleroma.Healthcheck
   6   alias Pleroma.Repo
   7
   8   defstruct pool_size: 0,
   9             active: 0,
  10             idle: 0,
  11             memory_used: 0,
  12             healthy: true
  13
  14   @type t :: %__MODULE__{
  15           pool_size: non_neg_integer(),
  16           active: non_neg_integer(),
  17           idle: non_neg_integer(),
  18           memory_used: number(),
  19           healthy: boolean()
  20         }
  21
  22   @spec system_info() :: t()
  23   def system_info do
  24     %Healthcheck{
  25       memory_used: Float.round(:erlang.memory(:total) / 1024 / 1024, 2)
  26     }
  27     |> assign_db_info()
  28     |> check_health()
  29   end
  30
  31   defp assign_db_info(healthcheck) do
  32     database = Application.get_env(:pleroma, Repo)[:database]
  33
  34     query =
  35       "select state, count(pid) from pg_stat_activity where datname = '#{database}' group by state;"
  36
  37     result = Repo.query!(query)
  38     pool_size = Application.get_env(:pleroma, Repo)[:pool_size]
  39
  40     db_info =
  41       Enum.reduce(result.rows, %{active: 0, idle: 0}, fn [state, cnt], states ->
  42         if state == "active" do
  43           Map.put(states, :active, states.active + cnt)
  44         else
  45           Map.put(states, :idle, states.idle + cnt)
  46         end
  47       end)
  48       |> Map.put(:pool_size, pool_size)
  49
  50     Map.merge(healthcheck, db_info)
  51   end
  52
  53   @spec check_health(Healthcheck.t()) :: Healthcheck.t()
  54   def check_health(%{pool_size: pool_size, active: active} = check)
  55       when active >= pool_size do
  56     %{check | healthy: false}
  57   end
  58
  59   def check_health(check), do: check
  60 end