send email with gmail (techschool#80)

Co-authored-by: phamlequang <phamlequang@gmail.com>

Makefile

@@ -37,7 +37,7 @@ sqlc:
 	sqlc generate
 
 test:
-	go test -v -cover ./...
+	go test -v -cover -short ./...
 
 server:
 	go run main.go

README.md

@@ -99,8 +99,9 @@ This course is designed with a lot of details, so that everyone, even with very
 
 - Lecture #54: [Implement background worker in Go with Redis and Asynq](https://www.youtube.com/watch?v=XOXdYs8mKkI&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=54)
 - Lecture #55: [Integrate async worker to Go web server](https://www.youtube.com/watch?v=eXYKGPEXocM&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=55)
-- Lecture #56: [Why you should send async tasks to Redis within a DB transaction](https://www.youtube.com/watch?v=ZfFxdPbgN88&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=56)
+- Lecture #56: [Send async tasks to Redis within a DB transaction](https://www.youtube.com/watch?v=ZfFxdPbgN88&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=56)
 - Lecture #57: [How to handle errors and print logs for Go Asynq workers](https://www.youtube.com/watch?v=YgfmPIJRg2U&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=57)
+- Lecture #58: [A bit of delay might be good for your async tasks](https://www.youtube.com/watch?v=ILNiZgseLUI&list=PLy_6D98if3ULEtXtNSY_2qN21VCKgoQAE&index=58)
 
 ## Simple bank service
 

app.env

@@ -8,3 +8,6 @@ TOKEN_SYMMETRIC_KEY=12345678901234567890123456789012
 ACCESS_TOKEN_DURATION=15m
 REFRESH_TOKEN_DURATION=24h
 REDIS_ADDRESS=0.0.0.0:6379
+EMAIL_SENDER_NAME=Simple Bank
+EMAIL_SENDER_ADDRESS=simplebanktest@gmail.com
+EMAIL_SENDER_PASSWORD=jekfcygyenvzekke

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/google/uuid v1.3.0
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.10.0
 	github.com/hibiken/asynq v0.23.0
+	github.com/jordan-wright/email v4.0.1-0.20210109023952-943e75fe5223+incompatible
 	github.com/lib/pq v1.10.5
 	github.com/o1egl/paseto v1.0.0
 	github.com/rakyll/statik v0.1.7

go.sum

@@ -638,6 +638,8 @@ github.com/jmoiron/sqlx v1.2.0/go.mod h1:1FEQNm3xlJgrMD+FBdI9+xvCksHtbpVBBw5dYhB
 github.com/jmoiron/sqlx v1.3.1/go.mod h1:2BljVx/86SuTyjE+aPYlHCTNvZrnJXghYGpNiXLBMCQ=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
+github.com/jordan-wright/email v4.0.1-0.20210109023952-943e75fe5223+incompatible h1:jdpOPRN1zP63Td1hDQbZW73xKmzDvZHzVdNYxhnTMDA=
+github.com/jordan-wright/email v4.0.1-0.20210109023952-943e75fe5223+incompatible/go.mod h1:1c7szIrayyPPB/987hsnvNzLushdWf4o/79s3P08L8A=
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/json-iterator/go v1.1.7/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=

mail/sender.go

@@ -0,0 +1,65 @@
+package mail
+
+import (
+	"fmt"
+	"net/smtp"
+
+	"github.com/jordan-wright/email"
+)
+
+const (
+	smtpAuthAddress   = "smtp.gmail.com"
+	smtpServerAddress = "smtp.gmail.com:587"
+)
+
+type EmailSender interface {
+	SendEmail(
+		subject string,
+		content string,
+		to []string,
+		cc []string,
+		bcc []string,
+		attachFiles []string,
+	) error
+}
+
+type GmailSender struct {
+	name              string
+	fromEmailAddress  string
+	fromEmailPassword string
+}
+
+func NewGmailSender(name string, fromEmailAddress string, fromEmailPassword string) EmailSender {
+	return &GmailSender{
+		name:              name,
+		fromEmailAddress:  fromEmailAddress,
+		fromEmailPassword: fromEmailPassword,
+	}
+}
+
+func (sender *GmailSender) SendEmail(
+	subject string,
+	content string,
+	to []string,
+	cc []string,
+	bcc []string,
+	attachFiles []string,
+) error {
+	e := email.NewEmail()
+	e.From = fmt.Sprintf("%s <%s>", sender.name, sender.fromEmailAddress)
+	e.Subject = subject
+	e.HTML = []byte(content)
+	e.To = to
+	e.Cc = cc
+	e.Bcc = bcc
+
+	for _, f := range attachFiles {
+		_, err := e.AttachFile(f)
+		if err != nil {
+			return fmt.Errorf("failed to attach file %s: %w", f, err)
+		}
+	}
+
+	smtpAuth := smtp.PlainAuth("", sender.fromEmailAddress, sender.fromEmailPassword, smtpAuthAddress)
+	return e.Send(smtpServerAddress, smtpAuth)
+}

mail/sender_test.go

@@ -0,0 +1,30 @@
+package mail
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/techschool/simplebank/util"
+)
+
+func TestSendEmailWithGmail(t *testing.T) {
+	if testing.Short() {
+		t.Skip()
+	}
+
+	config, err := util.LoadConfig("..")
+	require.NoError(t, err)
+
+	sender := NewGmailSender(config.EmailSenderName, config.EmailSenderAddress, config.EmailSenderPassword)
+
+	subject := "A test email"
+	content := `
+	<h1>Hello world</h1>
+	<p>This is a test message from <a href="http://techschool.guru">Tech School</a></p>
+	`
+	to := []string{"techschool.guru@gmail.com"}
+	attachFiles := []string{"../README.md"}
+
+	err = sender.SendEmail(subject, content, to, nil, nil, attachFiles)
+	require.NoError(t, err)
+}

util/config.go

@@ -19,6 +19,9 @@ type Config struct {
 	TokenSymmetricKey    string        `mapstructure:"TOKEN_SYMMETRIC_KEY"`
 	AccessTokenDuration  time.Duration `mapstructure:"ACCESS_TOKEN_DURATION"`
 	RefreshTokenDuration time.Duration `mapstructure:"REFRESH_TOKEN_DURATION"`
+	EmailSenderName      string        `mapstructure:"EMAIL_SENDER_NAME"`
+	EmailSenderAddress   string        `mapstructure:"EMAIL_SENDER_ADDRESS"`
+	EmailSenderPassword  string        `mapstructure:"EMAIL_SENDER_PASSWORD"`
 }
 
 // LoadConfig reads configuration from file or environment variables.

worker/task_send_verify_email.go

@@ -2,7 +2,6 @@ package worker
 
 import (
 	"context"
-	"database/sql"
 	"encoding/json"
 	"fmt"
 
@@ -45,9 +44,9 @@ func (processor *RedisTaskProcessor) ProcessTaskSendVerifyEmail(ctx context.Cont
 
 	user, err := processor.store.GetUser(ctx, payload.Username)
 	if err != nil {
-		if err == sql.ErrNoRows {
-			return fmt.Errorf("user doesn't exist: %w", asynq.SkipRetry)
-		}
+		// if err == sql.ErrNoRows {
+		// 	return fmt.Errorf("user doesn't exist: %w", asynq.SkipRetry)
+		// }
 		return fmt.Errorf("failed to get user: %w", err)
 	}