Add a relationship between a user and links.

lib/link_shortener/accounts/user.ex

@@ -2,12 +2,15 @@ defmodule LinkShortener.Accounts.User do
   use Ecto.Schema
   import Ecto.Changeset
 
+  alias LinkShortener.Links.Link
+
   schema "users" do
     field :email, :string
     field :password, :string, virtual: true, redact: true
     field :hashed_password, :string, redact: true
     field :current_password, :string, virtual: true, redact: true
     field :confirmed_at, :utc_datetime
+    has_many :links, Link
 
     timestamps(type: :utc_datetime)
   end

lib/link_shortener/links/link.ex

@@ -3,10 +3,13 @@ defmodule LinkShortener.Links.Link do
   import Ecto.Changeset
   import Ecto.Query
 
+  alias LinkShortener.Accounts.User
+
   schema "links" do
     field :name, :string
     field :url, :string
     field :shorten, :string
+    belongs_to :user, User
 
     timestamps()
   end
@@ -14,8 +17,8 @@ defmodule LinkShortener.Links.Link do
   @doc false
   def changeset(link, attrs) do
     link
-    |> cast(attrs, [:name, :url, :shorten])
+    |> cast(attrs, [:name, :url, :shorten, :user_id])
-    |> validate_required([:url, :shorten])
+    |> validate_required([:url, :shorten, :user_id])
     |> unique_constraint(:shorten)
   end
 end

priv/repo/migrations/20240901105600_add_relationship_between_users_and_links.exs

@@ -0,0 +1,11 @@
+defmodule LinkShortener.Repo.Migrations.AddRelationshipBetweenUsersAndLinks do
+  use Ecto.Migration
+
+  def change do
+    alter table(:links) do
+      add :user_id, references(:users, on_delete: :delete_all), null: false
+    end
+
+    create index(:links, [:user_id])
+  end
+end