refactor: project structure

pkg/email/email_test.go

@@ -0,0 +1,210 @@
+package email
+
+import (
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net/smtp"
+	"os"
+	"testing"
+
+	"github.com/joho/godotenv"
+	"github.com/kelseyhightower/envconfig"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type config struct {
+	MailUser     string `required:"false" split_words:"true"`
+	MailPassword string `required:"false" split_words:"true"`
+	MailHost     string `required:"false" split_words:"true"`
+	MailPort     string `required:"false" split_words:"true"`
+	MailFrom     string `required:"false" split_words:"true"`
+	MailTo       string `required:"false" split_words:"true"`
+}
+
+func newConfig(envFile string) *config {
+	if envFile != "" {
+		err := godotenv.Load(envFile)
+		if err != nil {
+			panic(fmt.Errorf("godotenv.Load: %w", err))
+		}
+	}
+
+	cfg := &config{}
+	err := envconfig.Process("", cfg)
+	if err != nil {
+		panic(fmt.Errorf("envconfig.Process: %w", err))
+	}
+
+	return cfg
+}
+
+type mockWriter struct{}
+
+func (w *mockWriter) Close() error {
+	return nil
+}
+func (w *mockWriter) Write(p []byte) (n int, err error) {
+	return 10, nil
+}
+
+// Mock SMTP Client
+type mockSMTP struct{}
+
+func (m *mockSMTP) StartTLS(*tls.Config) error {
+	return nil
+}
+func (m *mockSMTP) Auth(a smtp.Auth) error {
+	return nil
+}
+func (m *mockSMTP) Close() error {
+	return nil
+}
+func (m *mockSMTP) Data() (io.WriteCloser, error) {
+	return &mockWriter{}, nil
+}
+func (m *mockSMTP) Mail(from string) error {
+	return nil
+}
+func (m *mockSMTP) Quit() error {
+	return nil
+}
+func (m *mockSMTP) Rcpt(to string) error {
+	return nil
+}
+
+func TestNewConfig_MissingEnvFile(t *testing.T) {
+	assert.Panics(t, func() { newConfig(".missing_env_file") })
+}
+
+func TestMockSendEmail(t *testing.T) {
+	service := &EmailService{
+		auth: smtp.PlainAuth("", "", "", ""),
+		host: "",
+		port: "",
+		from: "",
+		tlsconfig: &tls.Config{
+			InsecureSkipVerify: true,
+			ServerName:         "",
+		},
+		dial: func(hostPort string) (SMTPClientIface, error) {
+			return &mockSMTP{}, nil
+		},
+	}
+
+	emailData := EmailMessage{
+		To:      "test@example.com",
+		Subject: "Test Email",
+		Body:    "This is a test email.",
+	}
+
+	err := service.SendEmail(emailData)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+}
+
+func TestSendEmail(t *testing.T) {
+	cfg := newConfig(".env.test")
+
+	mailSrv := NewMailService(MailServiceConfig{
+		Auth: smtp.PlainAuth("", cfg.MailUser, cfg.MailPassword, cfg.MailHost),
+		Host: cfg.MailHost,
+		Port: cfg.MailPort,
+		From: cfg.MailFrom,
+	})
+
+	data := EmailMessage{
+		To:      cfg.MailTo,
+		Subject: "Mail Sender",
+		Body:    "Hello this is a test email",
+	}
+	require.NoError(t, mailSrv.SendEmail(data))
+}
+
+func TestSendEmail_FailedAuthentication(t *testing.T) {
+	cfg := newConfig(".env.test")
+	// set up authentication to fail
+	mailSrv := NewMailService(MailServiceConfig{
+		Auth: smtp.PlainAuth("", "wronguser", "wrongpassword", cfg.MailHost),
+		Host: cfg.MailHost,
+		Port: cfg.MailPort,
+		From: cfg.MailFrom,
+	})
+	data := EmailMessage{
+		To:      cfg.MailTo,
+		Subject: "Test Email",
+		Body:    "This is a test email.",
+	}
+	err := mailSrv.SendEmail(data)
+	assert.Error(t, err)
+}
+
+func TestSendEmail_InvalidRecipient(t *testing.T) {
+	cfg := newConfig(".env.test")
+	mailSrv := NewMailService(MailServiceConfig{
+		Auth: smtp.PlainAuth("", cfg.MailUser, cfg.MailPassword, cfg.MailHost),
+		Host: cfg.MailHost,
+		Port: cfg.MailPort,
+		From: cfg.MailFrom,
+	})
+	data := EmailMessage{
+		To:      "invalid_email",
+		Subject: "Test Email",
+		Body:    "This is a test email.",
+	}
+	err := mailSrv.SendEmail(data)
+	assert.Error(t, err)
+}
+
+func TestSendEmailWithAttachments(t *testing.T) {
+	cfg := newConfig(".env.test")
+
+	mailSrv := NewMailService(MailServiceConfig{
+		Auth: smtp.PlainAuth("", cfg.MailUser, cfg.MailPassword, cfg.MailHost),
+		Host: cfg.MailHost,
+		Port: cfg.MailPort,
+		From: cfg.MailFrom,
+	})
+	reader, err := os.Open("testdata/attachment1.txt")
+	require.NoError(t, err)
+	defer reader.Close()
+
+	reader2, err := os.Open("testdata/attachment2.txt")
+	require.NoError(t, err)
+	defer reader2.Close()
+
+	reader3, err := os.Open("testdata/attachment3.txt")
+	require.NoError(t, err)
+	defer reader3.Close()
+
+	data := EmailMessage{
+		To:      cfg.MailTo,
+		Subject: "Mail Sender",
+		Body:    "Hello this is a test email",
+		Attachments: []EmailAttachment{
+			{
+				Title: "attachment1.txt",
+				File:  reader,
+			},
+			{
+				Title: "attachment2.txt",
+				File:  reader2,
+			},
+			{
+				Title: "attachment3.txt",
+				File:  reader3,
+			},
+		},
+	}
+	err = mailSrv.SendEmail(data)
+	require.NoError(t, err)
+}
+
+func TestWithAttachments(t *testing.T) {
+	msg := newMessage("from", "to", "subject")
+	content, err := msg.withAttachments("body", nil)
+	require.NoError(t, err)
+	assert.Greater(t, len(content), 0)
+}