Add initial auditing settings operations

lib/trento/auditing.ex

@@ -0,0 +1,79 @@
+defmodule Trento.Auditing do
+  @moduledoc """
+  Auditing module
+  """
+
+  require Logger
+
+  require Trento.Auditing.RetentionPeriodUnit, as: RetentionPeriodUnit
+
+  alias Trento.Auditing.Settings
+
+  alias Trento.Repo
+
+  @spec get_settings() ::
+          {:ok, Settings.t()} | {:error, :auditing_settings_not_configured}
+  def get_settings do
+    case Repo.one(Settings.base_query()) do
+      %Settings{} = settings -> {:ok, settings}
+      nil -> {:error, :auditing_settings_not_configured}
+    end
+  end
+
+  @spec save_retention_period(integer(), RetentionPeriodUnit.t()) ::
+          {:ok, Settings.t()} | {:error, :auditing_settings_already_configured}
+  def save_retention_period(retention_period, unit \\ RetentionPeriodUnit.days()) do
+    with {:ok, :auditing_settings_not_configured} <- ensure_no_settings_configured() do
+      nil
+      |> save_or_update_settings(retention_period, unit)
+      |> log_error("Error while saving auditing retention period")
+    end
+  end
+
+  @spec change_retention_period(integer(), RetentionPeriodUnit.t()) :: {:ok, Settings.t()}
+  def change_retention_period(retention_period, unit \\ RetentionPeriodUnit.days()) do
+    with {:ok, settings} <- get_settings() do
+      settings
+      |> save_or_update_settings(retention_period, unit)
+      |> log_error("Error while updating auditing retention period")
+    end
+  end
+
+  defp ensure_no_settings_configured do
+    case Repo.one(Settings.base_query()) do
+      nil ->
+        {:ok, :auditing_settings_not_configured}
+
+      %Settings{} ->
+        Logger.error("Error: Auditing settings already configured.")
+        {:error, :auditing_settings_already_configured}
+    end
+  end
+
+  defp save_or_update_settings(current_retention_period, retention_period, unit) do
+    case current_retention_period do
+      nil ->
+        %Settings{}
+        |> Settings.changeset(%{
+          retention_period: retention_period,
+          retention_period_unit: unit
+        })
+        |> Repo.insert()
+
+      %Settings{} ->
+        current_retention_period
+        |> Settings.changeset(%{
+          retention_period: retention_period,
+          retention_period_unit: unit
+        })
+        |> Repo.update()
+    end
+  end
+
+  defp log_error({:error, _} = error, message) do
+    Logger.error("#{message}: #{inspect(error)}")
+    error
+  end
+
+  defp log_error(result, _), do: result
+end

test/support/factory.ex

@@ -9,6 +9,7 @@ defmodule Trento.Factory do
   require Trento.Enums.Health, as: Health
   require Trento.SoftwareUpdates.Enums.AdvisoryType, as: AdvisoryType
   require Trento.SoftwareUpdates.Enums.SoftwareUpdatesHealth, as: SoftwareUpdatesHealth
+  require Trento.Auditing.RetentionPeriodUnit, as: RetentionPeriodUnit
 
   alias Faker.Random.Elixir, as: RandomElixir
 
@@ -124,6 +125,8 @@ defmodule Trento.Factory do
     InstallationSettings
   }
 
+  alias Trento.Auditing.Settings, as: AuditingSettings
+
   use ExMachina.Ecto, repo: Trento.Repo
 
   def host_registered_event_factory do
@@ -932,4 +935,12 @@ defmodule Trento.Factory do
     )
     |> X509.Certificate.to_pem()
   end
+
+  def auditing_settings_factory do
+    %AuditingSettings{
+      type: :auditing_settings,
+      retention_period: Enum.random(1..30),
+      retention_period_unit: Faker.Util.pick(RetentionPeriodUnit.values())
+    }
+  end
 end

test/trento/auditing_test.exs

@@ -0,0 +1,271 @@
+defmodule Trento.AuditingTest do
+  use ExUnit.Case
+  use Trento.DataCase
+
+  import Mox
+
+  import Trento.Factory
+
+  alias Trento.Auditing
+  alias Trento.Auditing.Settings
+
+  require Trento.Auditing.RetentionPeriodUnit, as: RetentionPeriodUnit
+
+  setup :verify_on_exit!
+
+  describe "retrieving auditing settings" do
+    test "should return an error when settings are not available" do
+      assert {:error, :auditing_settings_not_configured} == Auditing.get_settings()
+    end
+
+    test "should return settings" do
+      %{
+        retention_period: retention_period,
+        retention_period_unit: retention_period_unit
+      } = insert(:auditing_settings)
+
+      assert {:ok,
+              %Settings{
+                retention_period: ^retention_period,
+                retention_period_unit: ^retention_period_unit
+              }} = Auditing.get_settings()
+    end
+  end
+
+  @validation_scenarios [
+    %{
+      invalid_retention_periods: [-1, 0],
+      expected_errors: [
+        retention_period:
+          {"must be greater than %{number}",
+           [validation: :number, kind: :greater_than, number: 0]}
+      ]
+    },
+    %{
+      invalid_retention_periods: [nil, "", "  "],
+      expected_errors: [retention_period: {"can't be blank", [validation: :required]}]
+    }
+  ]
+
+  describe "saving auditing settings" do
+    test "should not accept settings if previously saved" do
+      insert(:auditing_settings)
+
+      assert {:error, :auditing_settings_already_configured} =
+               Auditing.save_retention_period(42, RetentionPeriodUnit.weeks())
+    end
+
+    test "should not accept invalid retention periods" do
+      for %{
+            invalid_retention_periods: invalid_retention_periods,
+            expected_errors: expected_errors
+          } <- @validation_scenarios do
+        Enum.each(invalid_retention_periods, fn invalid_retention_period ->
+          retention_period_unit = Faker.Util.pick(RetentionPeriodUnit.values())
+
+          assert {:error,
+                  %{
+                    errors: ^expected_errors
+                  }} =
+                   Auditing.save_retention_period(invalid_retention_period, retention_period_unit)
+        end)
+      end
+    end
+
+    test "should not accept unsupported retention period units" do
+      for retention_period_unit <- [:foo, :bar, :baz] do
+        assert {:error,
+                %{
+                  errors: [
+                    retention_period_unit: {"is invalid", _}
+                  ]
+                }} = Auditing.save_retention_period(42, retention_period_unit)
+      end
+    end
+
+    scenarios = [
+      %{
+        name: "default retention period unit",
+        retention_period: 42,
+        expected_retention_period_unit: RetentionPeriodUnit.days()
+      },
+      %{
+        name: "days",
+        retention_period: 1,
+        retention_period_unit: RetentionPeriodUnit.days()
+      },
+      %{
+        name: "weeks",
+        retention_period: 3,
+        retention_period_unit: RetentionPeriodUnit.weeks()
+      },
+      %{
+        name: "months",
+        retention_period: 5,
+        retention_period_unit: RetentionPeriodUnit.months()
+      },
+      %{
+        name: "years",
+        retention_period: 7,
+        retention_period_unit: RetentionPeriodUnit.years()
+      }
+    ]
+
+    for %{name: name} = scenario <- scenarios do
+      @scenario scenario
+
+      test "should save valid retention periods #{name}" do
+        %{retention_period: retention_period} = @scenario
+
+        expected_retention_period_unit =
+          Map.get(@scenario, :retention_period_unit, RetentionPeriodUnit.days())
+
+        case Map.has_key?(@scenario, :retention_period_unit) do
+          true ->
+            retention_period_unit = Map.fetch!(@scenario, :retention_period_unit)
+
+            assert {:ok,
+                    %Settings{
+                      retention_period: ^retention_period,
+                      retention_period_unit: ^expected_retention_period_unit
+                    }} =
+                     Auditing.save_retention_period(retention_period, retention_period_unit)
+
+          false ->
+            assert {:ok,
+                    %Settings{
+                      retention_period: ^retention_period,
+                      retention_period_unit: RetentionPeriodUnit.days()
+                    }} =
+                     Auditing.save_retention_period(retention_period)
+        end
+      end
+    end
+  end
+
+  describe "changing auditing settings" do
+    test "should not be able to change retention time if no auditing settings were previously saved" do
+      assert {:error, :auditing_settings_not_configured} ==
+               Auditing.change_retention_period(42, RetentionPeriodUnit.days())
+    end
+
+    test "should not accept invalid retention periods" do
+      insert(:auditing_settings)
+
+      for %{
+            invalid_retention_periods: invalid_retention_periods,
+            expected_errors: expected_errors
+          } <- @validation_scenarios do
+        Enum.each(invalid_retention_periods, fn invalid_retention_period ->
+          retention_period_unit = Faker.Util.pick(RetentionPeriodUnit.values())
+
+          assert {:error,
+                  %{
+                    errors: ^expected_errors
+                  }} =
+                   Auditing.change_retention_period(
+                     invalid_retention_period,
+                     retention_period_unit
+                   )
+        end)
+      end
+    end
+
+    test "should not accept unsupported retention period units" do
+      insert(:auditing_settings)
+
+      for retention_period_unit <- [:foo, :bar, :baz] do
+        assert {:error,
+                %{
+                  errors: [
+                    retention_period_unit: {"is invalid", _}
+                  ]
+                }} = Auditing.change_retention_period(42, retention_period_unit)
+      end
+    end
+
+    scenarios = [
+      %{
+        name: "default retention period unit",
+        retention_period: 42,
+        expected_retention_period_unit: RetentionPeriodUnit.days()
+      },
+      %{
+        name: "days",
+        retention_period: 1,
+        retention_period_unit: RetentionPeriodUnit.days()
+      },
+      %{
+        name: "weeks",
+        retention_period: 3,
+        retention_period_unit: RetentionPeriodUnit.weeks()
+      },
+      %{
+        name: "months",
+        retention_period: 5,
+        retention_period_unit: RetentionPeriodUnit.months()
+      },
+      %{
+        name: "years",
+        retention_period: 7,
+        retention_period_unit: RetentionPeriodUnit.years()
+      }
+    ]
+
+    for %{name: name} = scenario <- scenarios do
+      @scenario scenario
+
+      test "should successfully change retention periods #{name}" do
+        insert(:auditing_settings,
+          retention_period: 92,
+          retention_period_unit: RetentionPeriodUnit.years()
+        )
+
+        %{retention_period: retention_period} = @scenario
+
+        expected_retention_period_unit =
+          Map.get(@scenario, :retention_period_unit, RetentionPeriodUnit.days())
+
+        case Map.has_key?(@scenario, :retention_period_unit) do
+          true ->
+            retention_period_unit = Map.fetch!(@scenario, :retention_period_unit)
+
+            assert {:ok,
+                    %Settings{
+                      retention_period: ^retention_period,
+                      retention_period_unit: ^expected_retention_period_unit
+                    }} =
+                     Auditing.change_retention_period(retention_period, retention_period_unit)
+
+          false ->
+            assert {:ok,
+                    %Settings{
+                      retention_period: ^retention_period,
+                      retention_period_unit: RetentionPeriodUnit.days()
+                    }} =
+                     Auditing.change_retention_period(retention_period)
+        end
+      end
+    end
+
+    test "should successfully handle unchanging retention periods" do
+      initial_retention_period = 42
+      initial_retention_period_unit = RetentionPeriodUnit.days()
+
+      insert(:auditing_settings,
+        retention_period: initial_retention_period,
+        retention_period_unit: initial_retention_period_unit
+      )
+
+      assert {:ok,
+              %Settings{
+                retention_period: ^initial_retention_period,
+                retention_period_unit: ^initial_retention_period_unit
+              }} =
+               Auditing.change_retention_period(
+                 initial_retention_period,
+                 initial_retention_period_unit
+               )
+    end
+  end
+end