Add base infra to store assets

lib/music_library/assets.ex

@@ -0,0 +1,10 @@
+defmodule MusicLibrary.Assets do
+  alias MusicLibrary.Assets.Asset
+  alias MusicLibrary.Repo
+
+  def store(params) do
+    %Asset{}
+    |> Asset.changeset(params)
+    |> Repo.insert()
+  end
+end

lib/music_library/assets/asset.ex

@@ -0,0 +1,36 @@
+defmodule MusicLibrary.Assets.Asset do
+  use Ecto.Schema
+
+  import Ecto.Changeset
+
+  @primary_key {:hash, :string, autogenerate: false}
+  schema "assets" do
+    field :content, :binary
+    field :format, :string
+    field :properties, :map, default: %{}, read_after_writes: true
+
+    timestamps(type: :utc_datetime)
+  end
+
+  def changeset(asset, attrs) do
+    asset
+    |> cast(attrs, [:content, :format, :properties])
+    |> validate_required([:content, :format])
+    |> generate_hash()
+    |> unique_constraint(:hash)
+  end
+
+  defp generate_hash(changeset) do
+    case get_change(changeset, :content) do
+      nil ->
+        changeset
+
+      content ->
+        put_change(changeset, :hash, hash(content))
+    end
+  end
+
+  defp hash(content) do
+    :crypto.hash(:sha256, content) |> Base.encode16()
+  end
+end