Associate artists and records

lib/music_library/records/artist.ex

@@ -2,6 +2,8 @@ defmodule MusicLibrary.Records.Artist do
   use Ecto.Schema
   import Ecto.Changeset
 
+  alias MusicLibrary.{Records.ArtistRecord, Records.Record}
+
   @primary_key {:id, :binary_id, autogenerate: true}
   @foreign_key_type :binary_id
   schema "artists" do
@@ -9,6 +11,8 @@ defmodule MusicLibrary.Records.Artist do
     field :image, :string
     field :musicbrainz_id, Ecto.UUID
 
+    many_to_many :records, Record, join_through: ArtistRecord
+
     timestamps(type: :utc_datetime)
   end
 

lib/music_library/records/artist_record.ex

@@ -0,0 +1,20 @@
+defmodule MusicLibrary.Records.ArtistRecord do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+  schema "artists_records" do
+    field :artist_id, :binary_id
+    field :record_id, :binary_id
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @doc false
+  def changeset(artist_record, attrs) do
+    artist_record
+    |> cast(attrs, [])
+    |> validate_required([])
+  end
+end

lib/music_library/records/record.ex

@@ -2,6 +2,8 @@ defmodule MusicLibrary.Records.Record do
   use Ecto.Schema
   import Ecto.Changeset
 
+  alias MusicLibrary.{Records.Artist, Records.ArtistRecord}
+
   @primary_key {:id, :binary_id, autogenerate: true}
   @foreign_key_type :binary_id
   schema "records" do
@@ -12,6 +14,8 @@ defmodule MusicLibrary.Records.Record do
     field :musicbrainz_id, Ecto.UUID
     field :genres, {:array, :string}
 
+    many_to_many :artists, Artist, join_through: ArtistRecord
+
     timestamps(type: :utc_datetime)
   end
 

priv/repo/migrations/20240912134607_create_artists_records.exs

@@ -0,0 +1,16 @@
+defmodule MusicLibrary.Repo.Migrations.CreateArtistsRecords do
+  use Ecto.Migration
+
+  def change do
+    create table(:artists_records, primary_key: false) do
+      add :id, :binary_id, primary_key: true
+      add :artist_id, references(:artists, on_delete: :nothing, type: :binary_id)
+      add :record_id, references(:records, on_delete: :nothing, type: :binary_id)
+
+      timestamps(type: :utc_datetime)
+    end
+
+    create index(:artists_records, [:artist_id])
+    create index(:artists_records, [:record_id])
+  end
+end