fix: repaired smtp configuration for port 587

test/mv/mailer_smtp_config_test.exs

@@ -0,0 +1,89 @@
+defmodule Mv.MailerSmtpConfigTest do
+  @moduledoc """
+  Unit tests for Mv.Mailer.smtp_config/0.
+
+  Ensures both port 587 (STARTTLS) and 465 (implicit SSL) work:
+  - 587: sockopts must NOT contain :verify (gen_tcp:connect would raise ArgumentError).
+  - 465: sockopts MUST contain :verify so initial ssl:connect uses verify_none/verify_peer.
+  Uses ENV to drive config; async: false.
+  """
+  use Mv.DataCase, async: false
+
+  alias Mv.Mailer
+
+  defp set_smtp_env(key, value), do: System.put_env(key, value)
+
+  defp clear_smtp_env do
+    System.delete_env("SMTP_HOST")
+    System.delete_env("SMTP_PORT")
+    System.delete_env("SMTP_USERNAME")
+    System.delete_env("SMTP_PASSWORD")
+    System.delete_env("SMTP_PASSWORD_FILE")
+    System.delete_env("SMTP_SSL")
+  end
+
+  describe "smtp_config/0" do
+    test "port 587 (TLS): does not include :verify in sockopts so gen_tcp:connect does not crash" do
+      set_smtp_env("SMTP_HOST", "smtp.example.com")
+      set_smtp_env("SMTP_PORT", "587")
+      set_smtp_env("SMTP_SSL", "tls")
+
+      config = Mailer.smtp_config()
+
+      assert config != [], "expected non-empty config when SMTP_HOST is set"
+
+      sockopts = Keyword.get(config, :sockopts, [])
+
+      refute Keyword.has_key?(sockopts, :verify),
+             "for 587 gen_tcp is used first; sockopts must not contain :verify"
+    after
+      clear_smtp_env()
+    end
+
+    test "port 465 (SSL): includes :verify in sockopts so initial ssl:connect accepts verify mode" do
+      set_smtp_env("SMTP_HOST", "smtp.example.com")
+      set_smtp_env("SMTP_PORT", "465")
+      set_smtp_env("SMTP_SSL", "ssl")
+
+      config = Mailer.smtp_config()
+
+      assert config != []
+      sockopts = Keyword.get(config, :sockopts, [])
+
+      assert Keyword.has_key?(sockopts, :verify),
+             "for 465 initial connection is ssl:connect; sockopts must contain :verify"
+
+      assert Keyword.get(sockopts, :verify) in [:verify_none, :verify_peer]
+    after
+      clear_smtp_env()
+    end
+
+    test "builds TLS mode for port 587 (STARTTLS)" do
+      set_smtp_env("SMTP_HOST", "smtp.example.com")
+      set_smtp_env("SMTP_PORT", "587")
+      set_smtp_env("SMTP_SSL", "tls")
+
+      config = Mailer.smtp_config()
+
+      assert config != []
+      assert Keyword.get(config, :tls) == :always
+      assert Keyword.get(config, :ssl) == false
+    after
+      clear_smtp_env()
+    end
+
+    test "builds SSL mode for port 465 (implicit SSL)" do
+      set_smtp_env("SMTP_HOST", "smtp.example.com")
+      set_smtp_env("SMTP_PORT", "465")
+      set_smtp_env("SMTP_SSL", "ssl")
+
+      config = Mailer.smtp_config()
+
+      assert config != []
+      assert Keyword.get(config, :ssl) == true
+      assert Keyword.get(config, :tls) == :never
+    after
+      clear_smtp_env()
+    end
+  end
+end