Add a Schema module with Ecto attributes to configure primary keys as UUID

Author: gcauchon

config/config.exs

@@ -15,7 +15,9 @@ config :elixir_boilerplate, ElixirBoilerplateWeb.Endpoint,
     layout: false
   ]
 
-config :elixir_boilerplate, ElixirBoilerplate.Repo, start_apps_before_migration: [:ssl]
+config :elixir_boilerplate, ElixirBoilerplate.Repo,
+  migration_primary_key: [name: :id, type: :binary_id],
+  start_apps_before_migration: [:ssl]
 
 config :elixir_boilerplate, Corsica, allow_headers: :all
 

lib/elixir_boilerplate/planning/project.ex

@@ -0,0 +1,19 @@
+defmodule ElixirBoilerplate.Planning.Project do
+  use ElixirBoilerplate.Schema
+
+  schema "projects" do
+    field :description, :string
+    field :launch_at, :naive_datetime
+    field :next_milestone_at, :naive_datetime
+    field :title, :string
+
+    timestamps()
+  end
+
+  @doc false
+  def changeset(project, attrs) do
+    project
+    |> cast(attrs, ~w[title description next_milestone_at launch_at]a)
+    |> validate_required(~w[title description]a)
+  end
+end

lib/elixir_boilerplate/planning/task.ex

@@ -0,0 +1,22 @@
+defmodule ElixirBoilerplate.Planning.Task do
+  use ElixirBoilerplate.Schema
+
+  alias ElixirBoilerplate.Planning.Project
+
+  schema "tasks" do
+    field :description, :string
+    field :priority, :integer
+    field :due_at, :utc_datetime_usec
+
+    belongs_to :project, Project
+
+    timestamps()
+  end
+
+  @doc false
+  def changeset(task, attrs) do
+    task
+    |> cast(attrs, ~w[project_id description priority due_at]a)
+    |> validate_required(~w[project_id description]a)
+  end
+end

lib/elixir_boilerplate/schema.ex

@@ -0,0 +1,15 @@
+defmodule ElixirBoilerplate.Schema do
+  defmacro __using__(_) do
+    quote do
+      use Ecto.Schema
+
+      import Ecto.Changeset
+
+      alias Ecto.{Schema, UUID}
+
+      @primary_key {:id, :binary_id, autogenerate: true}
+      @foreign_key_type :binary_id
+      @timestamps_opts [type: :utc_datetime_usec]
+    end
+  end
+end

priv/repo/migrations/20230620204612_create_projects.exs

@@ -0,0 +1,14 @@
+defmodule ElixirBoilerplate.Repo.Migrations.CreateProjects do
+  use Ecto.Migration
+
+  def change do
+    create table(:projects) do
+      add :title, :string
+      add :description, :string
+      add :next_milestone_at, :utc_datetime_usec
+      add :launch_at, :utc_datetime_usec
+
+      timestamps()
+    end
+  end
+end

priv/repo/migrations/20230620205057_create_tasks.exs

@@ -0,0 +1,14 @@
+defmodule ElixirBoilerplate.Repo.Migrations.CreateTasks do
+  use Ecto.Migration
+
+  def change do
+    create table(:tasks) do
+      add :project_id, references(:projects), null: false
+      add :description, :string
+      add :priority, :integer
+      add :due_at, :utc_datetime_usec
+
+      timestamps()
+    end
+  end
+end

priv/repo/seeds.exs

@@ -2,10 +2,28 @@
 #
 #     mix run priv/repo/seeds.exs
 #
-# Inside the script, you can read and write to any of your
-# repositories directly:
+# Inside the script, you can read and write to any of your repositories directly:
 #
 #     ElixirBoilerplate.Repo.insert!(%ElixirBoilerplate.SomeSchema{})
 #
-# We recommend using the bang functions (`insert!`, `update!`
-# and so on) as they will fail if something goes wrong.
+# We recommend using the bang functions (`insert!`, `update!` and so on) as they
+# will fail if something goes wrong.
+
+alias ElixirBoilerplate.Planning.{Project, Task}
+alias ElixirBoilerplate.Repo
+
+project =
+  %Project{
+    title: "TODOs",
+    description: "A simple schema to showcase the way we are structuring our relational database data structures",
+    inserted_at: DateTime.utc_now(),
+    updated_at: DateTime.utc_now()
+  }
+  |> Repo.insert!()
+
+_tasks =
+  Repo.insert_all(Task, [
+    [description: "A first task in the project;", project_id: project.id, inserted_at: DateTime.utc_now(), updated_at: DateTime.utc_now()],
+    [description: "A second task", project_id: project.id, inserted_at: DateTime.utc_now(), updated_at: DateTime.utc_now()],
+    [description: "And one last one…", project_id: project.id, inserted_at: DateTime.utc_now(), updated_at: DateTime.utc_now()]
+  ])