add mailer

config/prod.exs

@@ -53,3 +53,14 @@ config :form, FormWeb.Endpoint,
   force_ssl: [rewrite_on: [:x_forwarded_proto]]
 #
 # Check `Plug.SSL` for all available options in `force_ssl`.
+
+# Email provider
+sendgrid_api_key =
+  System.get_env("SENDGRID_API_KEY") ||
+    raise """
+    environment variable SENDGRID_API_KEY is missing.
+    """
+
+config :form, FormWeb.Pow.Mailer,
+  adapter: Swoosh.Adapters.Sendgrid,
+  api_key: sendgrid_api_key

lib/form_web/pow_mailer.ex

@@ -1,16 +1,41 @@
 defmodule FormWeb.Pow.Mailer do
   use Pow.Phoenix.Mailer
+  use Swoosh.Mailer, otp_app: :form
+
+  import Swoosh.Email
+
   require Logger
 
-  def cast(%{user: user, subject: subject, text: text, html: html, assigns: _assigns}) do
-    # Build email struct to be used in `process/1`
+  @impl true
+  def cast(%{user: user, subject: subject, text: text, html: html}) do
+    %Swoosh.Email{}
+    |> to({"", user.email})
+    |> from({"My App", "myapp@example.com"})
+    |> subject(subject)
+    |> html_body(html)
+    |> text_body(text)
 
-    %{to: user.email, subject: subject, text: text, html: html}
+    # end
   end
 
+  @impl true
   def process(email) do
-    # Send email
-
     Logger.debug("E-mail sent: #{inspect(email)}")
+
+    if Mix.env() == :prod do
+      Task.start(fn ->
+        email
+        |> deliver()
+        |> log_warnings()
+      end)
+
+      :ok
+    end
+  end
+
+  defp log_warnings({:error, reason}) do
+    Logger.warn("Mailer backend failed with: #{inspect(reason)}")
   end
+
+  defp log_warnings({:ok, response}), do: {:ok, response}
 end

mix.exs

@@ -43,13 +43,15 @@ defmodule Form.MixProject do
       {:floki, ">= 0.30.0", only: :test},
       {:phoenix_live_dashboard, "~> 0.6"},
       {:esbuild, "~> 0.3", runtime: Mix.env() == :dev},
-      {:swoosh, "~> 1.3"},
       {:telemetry_metrics, "~> 0.6"},
       {:telemetry_poller, "~> 1.0"},
       {:gettext, "~> 0.18"},
       {:jason, "~> 1.2"},
       {:plug_cowboy, "~> 2.5"},
+      # auth provider
       {:pow, "~> 1.0.26"},
+      # email provider
+      {:swoosh, "~> 1.5"},
     ]
   end