feature: generic smtp provider for email notifications (#18)

replace sendgrid by generic smtp implementation for email notifications

api/api_test.go

@@ -11,7 +11,7 @@ import (
 
 	"github.com/vocdoni/saas-backend/account"
 	"github.com/vocdoni/saas-backend/db"
-	"github.com/vocdoni/saas-backend/notifications/testmail"
+	"github.com/vocdoni/saas-backend/notifications/smtp"
 	"github.com/vocdoni/saas-backend/test"
 	"go.vocdoni.io/dvote/apiclient"
 )
@@ -44,7 +44,7 @@ var testDB *db.MongoStorage
 
 // testMailService is the test mail service for the tests. Make it global so it
 // can be accessed by the tests directly.
-var testMailService *testmail.TestMail
+var testMailService *smtp.SMTPEmail
 
 // testURL helper function returns the full URL for the given path using the
 // test host and port.
@@ -161,14 +161,14 @@ func TestMain(m *testing.M) {
 		panic(err)
 	}
 	// create test mail service
-	testMailService = new(testmail.TestMail)
-	if err := testMailService.Init(&testmail.TestMailConfig{
+	testMailService = new(smtp.SMTPEmail)
+	if err := testMailService.New(&smtp.SMTPConfig{
 		FromAddress:  adminEmail,
-		SMTPUser:     adminUser,
+		SMTPUsername: adminUser,
 		SMTPPassword: adminPass,
-		Host:         mailHost,
+		SMTPServer:   mailHost,
 		SMTPPort:     smtpPort.Int(),
-		APIPort:      apiPort.Int(),
+		TestAPIPort:  apiPort.Int(),
 	}); err != nil {
 		panic(err)
 	}

api/users_test.go

@@ -3,8 +3,10 @@ package api
 import (
 	"bytes"
 	"context"
+	"fmt"
 	"io"
 	"net/http"
+	"regexp"
 	"strings"
 	"testing"
 
@@ -179,11 +181,13 @@ func TestVerifyAccountHandler(t *testing.T) {
 	// get the verification code from the email
 	mailBody, err := testMailService.FindEmail(context.Background(), testEmail)
 	c.Assert(err, qt.IsNil)
-	mailCode := strings.TrimPrefix(mailBody, VerificationCodeTextBody)
+	// create a regex to find the verification code in the email
+	mailCodeRgx := regexp.MustCompile(fmt.Sprintf(`%s(.{%d})`, VerificationCodeTextBody, VerificationCodeLength*2))
+	mailCode := mailCodeRgx.FindStringSubmatch(mailBody)
 	// verify the user
 	verification := mustMarshal(&UserVerification{
 		Email: testEmail,
-		Code:  mailCode,
+		Code:  mailCode[1],
 	})
 	req, err = http.NewRequest(http.MethodPost, testURL(verifyUserEndpoint), bytes.NewBuffer(verification))
 	c.Assert(err, qt.IsNil)
@@ -240,11 +244,14 @@ func TestRecoverAndResetPassword(t *testing.T) {
 	// get the verification code from the email
 	mailBody, err := testMailService.FindEmail(context.Background(), testEmail)
 	c.Assert(err, qt.IsNil)
-	verifyMailCode := strings.TrimPrefix(mailBody, VerificationCodeTextBody)
+	// create a regex to find the verification code in the email
+	mailCodeRgx := regexp.MustCompile(fmt.Sprintf(`%s(.{%d})`, VerificationCodeTextBody, VerificationCodeLength*2))
+	verifyMailCode := mailCodeRgx.FindStringSubmatch(mailBody)
+	c.Log(verifyMailCode[1])
 	// verify the user
 	verification := mustMarshal(&UserVerification{
 		Email: testEmail,
-		Code:  verifyMailCode,
+		Code:  verifyMailCode[1],
 	})
 	req, err = http.NewRequest(http.MethodPost, testURL(verifyUserEndpoint), bytes.NewBuffer(verification))
 	c.Assert(err, qt.IsNil)
@@ -262,12 +269,12 @@ func TestRecoverAndResetPassword(t *testing.T) {
 	// get the recovery code from the email
 	mailBody, err = testMailService.FindEmail(context.Background(), testEmail)
 	c.Assert(err, qt.IsNil)
-	passResetMailCode := strings.TrimPrefix(mailBody, VerificationCodeTextBody)
+	passResetMailCode := mailCodeRgx.FindStringSubmatch(mailBody)
 	// reset the password
 	newPassword := "password2"
 	resetPass := mustMarshal(&UserPasswordReset{
 		Email:       testEmail,
-		Code:        passResetMailCode,
+		Code:        passResetMailCode[1],
 		NewPassword: newPassword,
 	})
 	req, err = http.NewRequest(http.MethodPost, testURL(usersResetPasswordEndpoint), bytes.NewBuffer(resetPass))

cmd/service/main.go

@@ -11,7 +11,7 @@ import (
 	"github.com/vocdoni/saas-backend/account"
 	"github.com/vocdoni/saas-backend/api"
 	"github.com/vocdoni/saas-backend/db"
-	"github.com/vocdoni/saas-backend/notifications/sendgrid"
+	"github.com/vocdoni/saas-backend/notifications/smtp"
 	"github.com/vocdoni/saas-backend/notifications/twilio"
 	"go.vocdoni.io/dvote/apiclient"
 	"go.vocdoni.io/dvote/log"
@@ -28,12 +28,15 @@ func main() {
 	flag.StringP("vocdoniApi", "v", "https://api-dev.vocdoni.net/v2", "vocdoni node remote API URL")
 	flag.StringP("privateKey", "k", "", "private key for the Vocdoni account")
 	flag.BoolP("fullTransparentMode", "a", false, "allow all transactions and do not modify any of them")
-	flag.String("sendgridAPIKey", "", "SendGrid API key")
-	flag.String("sendgridFromAddress", "", "SendGrid from address")
-	flag.String("sendgridFromName", "Vocdoni", "SendGrid from name")
+	flag.String("smtpServer", "", "SMTP server")
+	flag.Int("smtpPort", 587, "SMTP port")
+	flag.String("smtpUsername", "", "SMTP username")
+	flag.String("smtpPassword", "", "SMTP password")
+	flag.String("emailFromAddress", "", "Email service from address")
+	flag.String("emailFromName", "Vocdoni", "Email service from name")
 	flag.String("twilioAccountSid", "", "Twilio account SID")
 	flag.String("twilioAuthToken", "", "Twilio auth token")
-	flag.String("twilioFromNumber", "", "Twilio from number")
+	flag.String("smsFromNumber", "", "SMS from number")
 	// parse flags
 	flag.Parse()
 	// initialize Viper
@@ -52,10 +55,13 @@ func main() {
 	}
 	mongoURL := viper.GetString("mongoURL")
 	mongoDB := viper.GetString("mongoDB")
-	// mail vars
-	sendgridAPIKey := viper.GetString("sendgridAPIKey")
-	sendgridFromAddress := viper.GetString("sendgridFromAddress")
-	sendgridFromName := viper.GetString("sendgridFromName")
+	// email vars
+	smtpServer := viper.GetString("smtpServer")
+	smtpPort := viper.GetInt("smtpPort")
+	smtpUsername := viper.GetString("smtpUsername")
+	smtpPassword := viper.GetString("smtpPassword")
+	emailFromAddress := viper.GetString("emailFromAddress")
+	emailFromName := viper.GetString("emailFromName")
 	// sms vars
 	twilioAccountSid := viper.GetString("twilioAccountSid")
 	twilioAuthToken := viper.GetString("twilioAuthToken")
@@ -93,24 +99,30 @@ func main() {
 		Account:             acc,
 		FullTransparentMode: fullTransparentMode,
 	}
-	// create email notifications service if the required parameters are set and
-	// include it in the API configuration
-	if sendgridAPIKey != "" && sendgridFromAddress != "" && sendgridFromName != "" {
-		apiConf.MailService = new(sendgrid.SendGridEmail)
-		if err := apiConf.MailService.Init(&sendgrid.SendGridConfig{
-			FromName:    sendgridFromName,
-			FromAddress: sendgridFromAddress,
-			APIKey:      sendgridAPIKey,
+	// overwrite the email notifications service with the SMTP service if the
+	// required parameters are set and include it in the API configuration
+	if smtpServer != "" && smtpUsername != "" && smtpPassword != "" {
+		if emailFromAddress == "" || emailFromName == "" {
+			log.Fatal("emailFromAddress and emailFromName are required")
+		}
+		apiConf.MailService = new(smtp.SMTPEmail)
+		if err := apiConf.MailService.New(&smtp.SMTPConfig{
+			FromName:     emailFromName,
+			FromAddress:  emailFromAddress,
+			SMTPServer:   smtpServer,
+			SMTPPort:     smtpPort,
+			SMTPUsername: smtpUsername,
+			SMTPPassword: smtpPassword,
 		}); err != nil {
 			log.Fatalf("could not create the email service: %v", err)
 		}
-		log.Infow("email service created", "from", fmt.Sprintf("%s <%s>", sendgridFromName, sendgridFromAddress))
+		log.Infow("email service created", "from", fmt.Sprintf("%s <%s>", emailFromName, emailFromAddress))
 	}
 	// create SMS notifications service if the required parameters are set and
 	// include it in the API configuration
 	if twilioAccountSid != "" && twilioAuthToken != "" && twilioFromNumber != "" {
 		apiConf.SMSService = new(twilio.TwilioSMS)
-		if err := apiConf.SMSService.Init(&twilio.TwilioConfig{
+		if err := apiConf.SMSService.New(&twilio.TwilioConfig{
 			AccountSid: twilioAccountSid,
 			AuthToken:  twilioAuthToken,
 			FromNumber: twilioFromNumber,

example.env

@@ -1,5 +1,8 @@
 VOCDONI_PORT=8080
 VOCDONI_SECRET=supersecret
 VOCDONI_PRIVATEKEY=vochain-private-key
-VOCDONI_SENDGRIDAPIKEY=SG.1234567890
-VOCDONI_SENDGRIDFROMADDRESS=[email protected]
+VOCDONI_SMTPSERVER=smpt.server.com
+VOCDONI_SMTPUSERNAME=admin
+VOCDONI_SMTPPASSWORD=password
+VOCDONI_EMAILFROMADDRESS=[email protected]
+VOCDONI_EMAILFROMADDRESS=[email protected]

go.mod

@@ -10,7 +10,6 @@ require (
 	github.com/go-chi/cors v1.2.1
 	github.com/go-chi/jwtauth/v5 v5.3.1
 	github.com/lestrrat-go/jwx/v2 v2.0.20
-	github.com/sendgrid/sendgrid-go v3.16.0+incompatible
 	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.18.2
 	github.com/testcontainers/testcontainers-go v0.32.0
@@ -297,7 +296,6 @@ require (
 	github.com/samber/lo v1.39.0 // indirect
 	github.com/sasha-s/go-deadlock v0.3.1 // indirect
 	github.com/segmentio/asm v1.2.0 // indirect
-	github.com/sendgrid/rest v2.6.9+incompatible // indirect
 	github.com/sethvargo/go-retry v0.2.4 // indirect
 	github.com/shirou/gopsutil v3.21.11+incompatible // indirect
 	github.com/shirou/gopsutil/v3 v3.23.12 // indirect

go.sum

@@ -1379,10 +1379,6 @@ github.com/segmentio/asm v1.2.0 h1:9BQrFxC+YOHJlTlHGkTrFWf59nbL3XnCoFLTwDCI7ys=
 github.com/segmentio/asm v1.2.0/go.mod h1:BqMnlJP91P8d+4ibuonYZw9mfnzI9HfxselHZr5aAcs=
 github.com/segmentio/kafka-go v0.1.0/go.mod h1:X6itGqS9L4jDletMsxZ7Dz+JFWxM6JHfPOCvTvk+EJo=
 github.com/segmentio/kafka-go v0.2.0/go.mod h1:X6itGqS9L4jDletMsxZ7Dz+JFWxM6JHfPOCvTvk+EJo=
-github.com/sendgrid/rest v2.6.9+incompatible h1:1EyIcsNdn9KIisLW50MKwmSRSK+ekueiEMJ7NEoxJo0=
-github.com/sendgrid/rest v2.6.9+incompatible/go.mod h1:kXX7q3jZtJXK5c5qK83bSGMdV6tsOE70KbHoqJls4lE=
-github.com/sendgrid/sendgrid-go v3.16.0+incompatible h1:i8eE6IMkiCy7vusSdacHHSBUpXyTcTXy/Rl9N9aZ/Qw=
-github.com/sendgrid/sendgrid-go v3.16.0+incompatible/go.mod h1:QRQt+LX/NmgVEvmdRw0VT/QgUn499+iza2FnDca9fg8=
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
 github.com/sethvargo/go-retry v0.2.4 h1:T+jHEQy/zKJf5s95UkguisicE0zuF9y7+/vgz08Ocec=
 github.com/sethvargo/go-retry v0.2.4/go.mod h1:1afjQuvh7s4gflMObvjLPaWgluLLyhA1wmVZ6KLpICw=

notifications/notifications.go

@@ -2,6 +2,10 @@ package notifications
 
 import "context"
 
+// Notification represents a notification to be sent, it can be an email or an
+// SMS. It contains the recipient's name, address, number, the subject and the
+// body of the message. The recipient's name and address are used for emails,
+// while the recipient's number is used for SMS.
 type Notification struct {
 	ToName    string
 	ToAddress string
@@ -10,7 +14,19 @@ type Notification struct {
 	Body      string
 }
 
+// NotificationService is the interface that must be implemented by any
+// notification service. It contains the methods New and SendNotification.
+// Init is used to initialize the service with the configuration, and
+// SendNotification is used to send a notification.
 type NotificationService interface {
-	Init(conf any) error
+	// New initializes the notification service with the configuration. Each
+	// service implementation can have its own configuration type, which is
+	// passed as an argument to this method and must be casted to the correct
+	// type inside the method.
+	New(conf any) error
+	// SendNotification sends a notification to the recipient. The notification
+	// contains the recipient's name, address, number, the subject and the body
+	// of the message. This method cannot be blocking, so it must return an
+	// error if the notification could not be sent or if the context is done.
 	SendNotification(context.Context, *Notification) error
 }