[#57] Receiver for storing system stats

config/prod.exs

@@ -28,7 +28,8 @@ config :poa_backend,
             port: 8181,
             ws_secret: "wssecret"
             ]},
-          {:store_eth_stats, POABackend.Receivers.EthStats, []}
+          {:store_eth_stats, POABackend.Receivers.Eth.Stats, []},
+          {:store_system_stats, POABackend.Receivers.System.Stats, []}
        ]
 
 # here we define the type of metrics we accept. We will create a GenStage Producer per each type
@@ -36,7 +37,8 @@ config :poa_backend,
        :metrics,
        [
          :ethereum_metrics,
-         :networking_metrics
+         :networking_metrics,
+         :system_metrics
        ]
 
 # here we have to define the relationship between receivers and metric types. The format is {receiver_id, [metric_type]}.
@@ -45,7 +47,8 @@ config :poa_backend,
        :subscriptions,
        [
          {:dashboard_receiver, [:ethereum_metrics, :networking_metrics]},
-         {:store_eth_stats, [:ethereum_metrics]}
+         {:store_eth_stats, [:ethereum_metrics]},
+         {:store_system_stats, [:system_metrics]}
        ]
 
 # here we define the configuration for the Authorisation endpoint

config/test.exs

@@ -20,14 +20,16 @@ config :poa_backend,
             port: 8181,
             ws_secret: "mywssecret"
             ]},
-          {:store_eth_stats, POABackend.Receivers.EthStats, []}
+          {:store_eth_stats, POABackend.Receivers.Eth.Stats, []},
+          {:store_system_stats, POABackend.Receivers.System.Stats, []}
        ]
 
 # here we define the type of metrics we accept. We will create a GenStage Producer per each type
 config :poa_backend,
        :metrics,
        [
-         :ethereum_metrics
+         :ethereum_metrics,
+         :system_metrics
        ]
 
 # here we have to define the relationship between receivers and metric types. The format is {receiver_id, [metric_type]}.
@@ -36,7 +38,8 @@ config :poa_backend,
        :subscriptions,
        [
          {:dashboard_receiver, [:ethereum_metrics]},
-         {:store_eth_stats, [:ethereum_metrics]}
+         {:store_eth_stats, [:ethereum_metrics]},
+         {:store_system_stats, [:system_metrics]}
        ]
 
 # here we define the configuration for the Authorisation endpoint

lib/poa_backend/receivers/eth/stats.ex

@@ -1,4 +1,4 @@
-defmodule POABackend.Receivers.EthStats do
+defmodule POABackend.Receivers.Eth.Stats do
   use POABackend.Receiver
 
   @moduledoc false

lib/poa_backend/receivers/models/system_stats.ex

@@ -0,0 +1,54 @@
+defmodule POABackend.Receivers.Models.SystemStats do
+  use Ecto.Schema
+
+  @moduledoc false
+
+  @primary_key false
+
+  schema "system_stats" do
+    field :date, :naive_datetime, primary_key: true
+    field :agent_id, :string, primary_key: true
+    field :cpu_load, :float
+    field :disk_usage, :integer
+    field :memory_usage, :float
+  end
+
+  @type t :: %__MODULE__{
+    date: NaiveDateTime.t,
+    agent_id: String.t,
+    cpu_load: Float.t,
+    disk_usage: Float.t,
+    memory_usage: Float.t
+  }
+
+  @spec new() :: __MODULE__.t
+  def new do
+    %__MODULE__{}
+  end
+
+  @spec date(__MODULE__.t, NaiveDateTime.t) :: __MODULE__.t
+  def date(eth_stats, date) do
+    %__MODULE__{eth_stats | date: date}
+  end
+
+  @spec agent_id(__MODULE__.t, String.t) :: __MODULE__.t
+  def agent_id(eth_stats, agent_id) do
+    %__MODULE__{eth_stats | agent_id: agent_id}
+  end
+
+  @spec cpu_load(__MODULE__.t, Float.t) :: __MODULE__.t
+  def cpu_load(eth_stats, cpu_load) do
+    %__MODULE__{eth_stats | cpu_load: cpu_load}
+  end
+
+  @spec disk_usage(__MODULE__.t, Float.t) :: __MODULE__.t
+  def disk_usage(eth_stats, disk_usage) do
+    %__MODULE__{eth_stats | disk_usage: disk_usage}
+  end
+
+  @spec memory_usage(__MODULE__.t, Float.t) :: __MODULE__.t
+  def memory_usage(eth_stats, memory_usage) do
+    %__MODULE__{eth_stats | memory_usage: memory_usage}
+  end
+
+end

lib/poa_backend/receivers/system/stats.ex

@@ -0,0 +1,50 @@
+defmodule POABackend.Receivers.System.Stats do
+  use POABackend.Receiver
+
+  @moduledoc false
+
+  alias POABackend.Protocol.Message
+  alias POABackend.Receivers.Models.SystemStats
+  alias POABackend.Receivers.Repo
+
+  def init_receiver(_args) do
+    {:ok, :no_state}
+  end
+
+  def metrics_received([%Message{agent_id: agent_id, data: %{"type" => "statistics", "body" => stats}}], _from, state) do
+    :ok = save_data(stats, agent_id)
+    {:ok, state}
+  end
+  def metrics_received(_metrics, _from, state) do
+    {:ok, state}
+  end
+
+  def handle_message(_message, state) do
+    {:ok, state}
+  end
+
+  def handle_inactive(_agent_id, state) do
+    {:ok, state}
+  end
+
+  def terminate(_state) do
+    :ok
+  end
+
+  defp save_data(%{"cpu_load" => cpu_load, "disk_usage" => disk_usage, "memory_usage" => memory_usage}, agent_id) do
+
+    SystemStats.new()
+    |> SystemStats.date(NaiveDateTime.utc_now())
+    |> SystemStats.agent_id(agent_id)
+    |> SystemStats.cpu_load(cpu_load)
+    |> SystemStats.disk_usage(disk_usage)
+    |> SystemStats.memory_usage(memory_usage)
+    |> Repo.insert()
+
+    :ok
+  end
+  defp save_data(_data, _agent_id) do
+    :ok
+  end
+
+end

priv/receivers/migrations/20180828215749_create_system_stats.exs

@@ -0,0 +1,13 @@
+defmodule POABackend.Receivers.Repo.Migrations.CreateSystemStats do
+  use Ecto.Migration
+
+  def change do
+    create table(:system_stats, primary_key: false) do
+      add :date, :naive_datetime, primary_key: true
+      add :agent_id, :string, primary_key: true
+      add :cpu_load, :float
+      add :disk_usage, :integer
+      add :memory_usage, :float
+    end
+  end
+end

test/ancillary/utils.ex

@@ -6,6 +6,7 @@ defmodule POABackend.Ancillary.Utils do
     :mnesia.clear_table(:banned_tokens)
 
     truncate(POABackend.Receivers.Models.EthStats)
+    truncate(POABackend.Receivers.Models.SystemStats)
   end
 
   defp truncate(schema) do

test/receivers/system_stats_test.exs

@@ -0,0 +1,51 @@
+defmodule Receivers.SystemStatsTest do
+  use ExUnit.Case
+
+  alias POABackend.Protocol.Message
+  alias POABackend.Ancillary.Utils
+  alias POABackend.Receivers.Repo
+  alias POABackend.Receivers.Models.SystemStats
+
+  setup do
+    Utils.clear_db()
+
+    on_exit fn ->
+      Utils.clear_db()
+    end
+
+    []
+  end
+
+  test "storing stats" do
+    assert [] == Repo.all(SystemStats)
+
+    POABackend.Metric.add(:system_metrics, [raw_stats()])
+
+    # this will create an entry in the DB
+    Process.sleep(5000)
+
+    [stats] = Repo.all(SystemStats)
+
+    assert "agent_id1" == stats.agent_id
+    assert 9.1234 == stats.cpu_load
+    assert 75 == stats.disk_usage
+    assert 10.1234 == stats.memory_usage
+  end
+
+  defp raw_stats do
+    stats = %{
+      "cpu_load" => 9.1234,
+      "disk_usage" => 75,
+      "memory_usage" => 10.1234
+    }
+
+    %Message{
+      agent_id: "agent_id1",
+      data: %{
+        "type" => "statistics",
+        "body" => stats
+        }
+      }
+  end
+
+end