Validate uniqueness on (type, value) columns of the contacts table

Author: smaximov

lib/blog/accounts/contact.ex

@@ -24,6 +24,7 @@ defmodule Blog.Accounts.Contact do
     contact
     |> cast(attrs, [:type, :value])
     |> validate_required([:type, :value])
+    |> unique_constraint(:value, name: :contacts_type_value_index)
   end
 
 end

test/blog/accounts/accounts_test.exs

@@ -15,4 +15,13 @@ defmodule Blog.AccountsTest do
     assert {:error, %Ecto.Changeset{}} = Accounts.create_user(attrs)
     assert ^contact_count = Repo.aggregate(Accounts.Contact, :count, :id)
   end
+
+  test "create_user/1 discards duplicate contacts" do
+    contact = %{type: "phone", value: "+1 000 000 0000"}
+
+    assert {:ok, _} = Accounts.create_user(%{contact: contact, name: "name", password: "password"})
+
+    assert {:error, changeset} = Accounts.create_user(%{contact: contact, name: "other", password: "password"})
+    assert "has already been taken" in errors_on(changeset).value
+  end
 end