Add activity log default ordering by occurrence date (#2758)

* Add activity log default ordering by occurrence date

* Add index on inserted at for ActivityLog

lib/trento/activity_log.ex

@@ -3,6 +3,8 @@ defmodule Trento.ActivityLog do
   Activity Log module provides functionality to manage activity log settings and track activity.
   """
 
+  import Ecto.Query
+
   require Logger
 
   require Trento.ActivityLog.RetentionPeriodUnit, as: RetentionPeriodUnit
@@ -40,7 +42,11 @@ defmodule Trento.ActivityLog do
   @spec list_activity_log() :: list(ActivityLog.t())
   def list_activity_log do
     # This will be made filterable/paginatable in a later PR
-    Repo.all(ActivityLog)
+    query =
+      from activity in ActivityLog,
+        order_by: [desc: activity.inserted_at]
+
+    Repo.all(query)
   end
 
   defp log_error({:error, _} = error, message) do

priv/repo/migrations/20240710062924_add_activity_log_intex.exs

@@ -0,0 +1,7 @@
+defmodule Trento.Repo.Migrations.AddActivityLogIntex do
+  use Ecto.Migration
+
+  def change do
+    create index(:activity_logs, [:inserted_at])
+  end
+end

test/trento/activity_log_test.exs

@@ -10,6 +10,7 @@ defmodule Trento.ActivityLogTest do
   require Trento.ActivityLog.RetentionPeriodUnit, as: RetentionPeriodUnit
 
   alias Trento.ActivityLog
+  alias Trento.ActivityLog.ActivityLog, as: ActivityLogEntry
   alias Trento.ActivityLog.RetentionTime
   alias Trento.ActivityLog.Settings
 
@@ -177,4 +178,27 @@ defmodule Trento.ActivityLogTest do
                )
     end
   end
+
+  describe "retrieving logged activity" do
+    test "should return an emtpty list" do
+      assert [] == ActivityLog.list_activity_log()
+    end
+
+    test "should return entries ordered by occurrence date" do
+      older_occurrence = Faker.DateTime.backward(1)
+      newer_occurrence = Faker.DateTime.forward(2)
+
+      insert(:activity_log_entry, inserted_at: newer_occurrence)
+      insert(:activity_log_entry, inserted_at: older_occurrence)
+
+      assert [
+               %ActivityLogEntry{
+                 inserted_at: ^newer_occurrence
+               },
+               %ActivityLogEntry{
+                 inserted_at: ^older_occurrence
+               }
+             ] = ActivityLog.list_activity_log()
+    end
+  end
 end