create follow schema for #13

lib/app/follow.ex

@@ -0,0 +1,31 @@
+defmodule App.Follow do
+  alias App.{Repo}
+  use Ecto.Schema
+  import Ecto.Changeset
+  require Logger
+  alias __MODULE__
+
+  schema "follows" do
+    field :follower_id, :integer
+    field :following_id, :integer
+    field :stop, :utc_datetime
+
+    timestamps()
+  end
+
+  @doc false
+  def changeset(follow, attrs) do
+    follow
+    |> cast(attrs, [:follower_id, :following_id, :stop])
+    |> validate_required([:follower_id, :following_id])
+  end
+
+  @doc """
+  Creates a `follow` record.
+  """
+  def create(attrs) do
+    %Follow{}
+    |> changeset(attrs)
+    |> Repo.insert()
+  end
+end

priv/repo/migrations/20240608144843_create_follows.exs

@@ -0,0 +1,13 @@
+defmodule App.Repo.Migrations.CreateFollows do
+  use Ecto.Migration
+
+  def change do
+    create table(:follows) do
+      add :follower_id, :integer
+      add :following_id, :integer
+      add :stop, :utc_datetime
+
+      timestamps()
+    end
+  end
+end

test/app/follow_test.exs

@@ -0,0 +1,12 @@
+defmodule App.FollowTest do
+  use App.DataCase
+
+  test "App.Follow.create/1" do
+    follow = %{
+      follower_id: 42,
+      following_id: 73
+    }
+    assert {:ok, inserted_follow} = App.Follow.create(follow)
+    assert inserted_follow.follower_id == follow.follower_id
+  end
+end