WIP

lib/customer_service/aggregates/customer.ex

@@ -0,0 +1,44 @@
+defmodule CustomerService.Aggregates.Customer do
+  defstruct [
+    :id,
+    :first_name,
+    :last_name,
+    :birth_date,
+    :gender,
+    :email,
+    :phone
+  ]
+
+  alias __MODULE__
+  alias Commanded.Aggregates.Aggregate
+  alias CustomerService.Commands
+  alias CustomerService.Events
+
+  @behaviour Aggregate
+  @impl Aggregate
+  def execute(%Customer{id: nil}, %Commands.CreateCustomer{} = cmd) do
+    %Events.CustomerCreated{
+      id: cmd.id,
+      first_name: cmd.first_name,
+      last_name: cmd.last_name,
+      birth_date: cmd.birth_date,
+      gender: cmd.gender,
+      email: cmd.email,
+      phone: cmd.phone
+    }
+  end
+
+  @impl Aggregate
+  def apply(%Customer{} = c, %Events.CustomerCreated{} = e) do
+    %Customer{
+      c
+      | id: e.id,
+        first_name: e.first_name,
+        last_name: e.last_name,
+        birth_date: e.birth_date,
+        gender: e.gender,
+        email: e.email,
+        phone: e.phone
+    }
+  end
+end

lib/customer_service/application.ex

@@ -0,0 +1,36 @@
+defmodule CustomerService.Application do
+  # See https://hexdocs.pm/elixir/Application.html
+  # for more information on OTP Applications
+  @moduledoc false
+
+  use Application
+
+  @impl true
+  def start(_type, _args) do
+    children = [
+      CustomerService.CommandedApp,
+      CustomerService.Repo,
+      CustomerService.Projectors.Customer,
+      CustomerServiceWeb.Telemetry,
+      {DNSCluster, query: Application.get_env(:customer_service, :dns_cluster_query) || :ignore},
+      {Phoenix.PubSub, name: CustomerService.PubSub},
+      # Start a worker by calling: CustomerService.Worker.start_link(arg)
+      # {CustomerService.Worker, arg},
+      # Start to serve requests, typically the last entry
+      CustomerServiceWeb.Endpoint
+    ]
+
+    # See https://hexdocs.pm/elixir/Supervisor.html
+    # for other strategies and supported options
+    opts = [strategy: :one_for_one, name: CustomerService.Supervisor]
+    Supervisor.start_link(children, opts)
+  end
+
+  # Tell Phoenix to update the endpoint configuration
+  # whenever the application is updated.
+  @impl true
+  def config_change(changed, _new, removed) do
+    CustomerServiceWeb.Endpoint.config_change(changed, removed)
+    :ok
+  end
+end

lib/customer_service/commanded_app.ex

@@ -0,0 +1,15 @@
+defmodule CustomerService.Router do
+  use Commanded.Commands.Router
+  alias CustomerService.Commands
+  alias CustomerService.Aggregates
+
+  identify(Aggregates.Customer, by: :id)
+  dispatch([Commands.CreateCustomer], to: Aggregates.Customer)
+end
+
+defmodule CustomerService.CommandedApp do
+  use Commanded.Application,
+    otp_app: :customer_service
+
+  router(CustomerService.Router)
+end

lib/customer_service/commands.ex

@@ -0,0 +1,11 @@
+defmodule CustomerService.Commands.CreateCustomer do
+  defstruct [
+    :id,
+    :first_name,
+    :last_name,
+    :birth_date,
+    :gender,
+    :email,
+    :phone
+  ]
+end

lib/customer_service/event_store.ex

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+defmodule CustomerService.EventStore do
+  use EventStore, otp_app: :customer_service
+end

lib/customer_service/events.ex

@@ -0,0 +1,12 @@
+defmodule CustomerService.Events.CustomerCreated do
+  @derive Jason.Encoder
+  defstruct [
+    :id,
+    :first_name,
+    :last_name,
+    :birth_date,
+    :gender,
+    :email,
+    :phone
+  ]
+end

lib/customer_service/projections/customer.ex

@@ -0,0 +1,28 @@
+defmodule CustomerService.Projections.Customer do
+  use Ecto.Schema
+
+  @derive {Jason.Encoder,
+           only: [
+             :id,
+             :first_name,
+             :last_name,
+             :birth_date,
+             :gender,
+             :email,
+             :phone,
+             :inserted_at,
+             :updated_at
+           ]}
+  @primary_key {:id, :binary_id, autogenerate: false}
+  @timestamps_opts [type: :utc_datetime_usec]
+  schema "customers" do
+    field :first_name, :string
+    field :last_name, :string
+    field :birth_date, :date
+    field :gender, :string
+    field :email, :string
+    field :phone, :string
+
+    timestamps()
+  end
+end

lib/customer_service/projectors/customer.ex

@@ -0,0 +1,31 @@
+defmodule CustomerService.Projectors.Customer do
+  use Commanded.Projections.Ecto,
+    application: CustomerService.CommandedApp,
+    repo: CustomerService.Repo,
+    name: "CustomerService.Projetors.Customer",
+    consistency: :strong
+
+  alias CustomerService.Events
+  alias CustomerService.Projections.Customer
+
+  project(%Events.CustomerCreated{} = event, fn multi ->
+    Ecto.Multi.insert(multi, :customer, %Customer{
+      id: event.id,
+      first_name: event.first_name,
+      last_name: event.last_name,
+      birth_date: event.birth_date,
+      gender: event.gender,
+      email: event.email,
+      phone: event.phone
+    })
+  end)
+
+  # project %Events.CustomerDeactivated{} = event, _metadata do
+  #   Ecto.Multi.update_all(
+  #     multi,
+  #     :deactivate_customer,
+  #     from(c in Customer, where: c.customer_id == ^event.customer_id),
+  #     set: [active: false]
+  #   )
+  # end
+end

lib/customer_service/repo.ex

@@ -0,0 +1,13 @@
+defmodule CustomerService.Repo do
+  use Ecto.Repo,
+    otp_app: :customer_service,
+    adapter: Ecto.Adapters.Postgres
+
+  @doc """
+  Dynamically loads the repository url from the
+  DATABASE_URL environment variable.
+  """
+  def init(_, opts) do
+    {:ok, Keyword.put(opts, :url, System.get_env("DATABASE_URL"))}
+  end
+end