Validate entries at changeset

lib/atomic/activities/enrollment.ex

@@ -5,6 +5,7 @@ defmodule Atomic.Activities.Enrollment do
   use Atomic.Schema
 
   alias Atomic.Accounts.User
+  alias Atomic.Activities
   alias Atomic.Activities.Session
 
   schema "enrollments" do
@@ -22,5 +23,21 @@ defmodule Atomic.Activities.Enrollment do
     enrollment
     |> cast(attrs, [:session_id, :user_id, :present])
     |> validate_required([:session_id, :user_id])
+    |> validate_max_entries()
+  end
+
+  @doc """
+    Validates if the maximum number of enrollments has been reached.
+  """
+  def validate_max_entries(changeset) do
+    sesion_id = get_field(changeset, :session_id)
+    session = Activities.get_session!(sesion_id)
+    enrolled = Activities.get_total_enrolled(session.id)
+
+    if session.maximum_entries <= enrolled do
+      add_error(changeset, :session_id, "Maximum number of enrollments reached.")
+    else
+      changeset
+    end
   end
 end

lib/atomic_web/live/activity_live/show.ex

@@ -55,26 +55,17 @@ defmodule AtomicWeb.ActivityLive.Show do
 
   @impl true
   def handle_event("enroll", _payload, socket) do
-    session_id = socket.assigns.id
-    current_user = socket.assigns.current_user
+    case Activities.create_enrollment(socket.assigns.id, socket.assigns.current_user) do
+      {:ok, _enrollment} ->
+        {:noreply,
+         socket
+         |> put_flash(:success, "Enrolled successufully!")
+         |> set_enrolled(socket.assigns.id, socket.assigns.current_user)}
 
-    if Activities.verify_maximum_enrollments?(session_id) do
-      case Activities.create_enrollment(session_id, current_user) do
-        {:ok, _enrollment} ->
-          {:noreply,
-           socket
-           |> put_flash(:success, "Enrolled successufully!")
-           |> set_enrolled(session_id, current_user)}
-
-        {:error, _error} ->
-          {:noreply,
-           socket
-           |> put_flash(:error, "Unable to enroll")}
-      end
-    else
-      {:noreply,
-       socket
-       |> put_flash(:error, "Maximum number of entries reached")}
+      {:error, changeset} ->
+        {:noreply,
+         socket
+         |> put_flash(:error, changeset.errors[:session_id] |> elem(0))}
     end
   end
 

test/atomic/activities_test.exs

@@ -147,7 +147,7 @@ defmodule Atomic.ActivitiesTest do
 
     test "update_enrollment/2 with valid data updates the enrollment" do
       enrollment = insert(:enrollment)
-      update_attrs = %{}
+      update_attrs = %{present: true}
 
       assert {:ok, %Enrollment{}} = Activities.update_enrollment(enrollment, update_attrs)
     end

test/support/factories/organizations_factory.ex

@@ -7,7 +7,7 @@ defmodule Atomic.Factories.OrganizationFactory do
 
   defmacro __using__(_opts) do
     quote do
-      @roles ~w(follower member admin owner)a
+      @roles ~w(member admin owner)a
 
       def organization_factory do
         %Organization{