app-cloudep-notification-service/internal/usecase/smtp.go

package usecase

import (
	"app-cloudep-notification-service/internal/config"
	"app-cloudep-notification-service/internal/domain/usecase"

	pool "code.30cm.net/digimon/library-go/worker_pool"
	"github.com/zeromicro/go-zero/core/logx"

	"context"

	"gopkg.in/gomail.v2"
)

type MailUseCaseParam struct {
	Conf config.Config
}

type MailUseCase struct {
	Host     string
	Port     int
	User     string
	Password string
	Pool     pool.WorkerPool
}

func (mu *MailUseCase) SendMail(_ context.Context, req usecase.MailReq) error {
	// 用 goroutine pool 送，否則會超時
	err := mu.Pool.Submit(func() {
		m := gomail.NewMessage()
		m.SetHeader("From", req.From)
		m.SetHeader("To", req.To)
		m.SetHeader("Subject", req.Subject)
		m.SetBody("text/html", req.Body)
		d := gomail.NewDialer(mu.Host, mu.Port, mu.User, mu.Password)
		if err := d.DialAndSend(m); err != nil {
			logx.WithCallerSkip(1).WithFields(
				logx.Field("func", "MailUseCase.SendMail"),
				logx.Field("req", req),
				logx.Field("err", err),
			).Error("failed to send mail by mailgun")
		}
	})

	return err
}

func MustMailgunUseCase(param MailUseCaseParam) usecase.MailClientUseCase {
	return &MailUseCase{
		Host:     param.Conf.SMTP.Host,
		Port:     param.Conf.SMTP.Port,
		User:     param.Conf.SMTP.User,
		Password: param.Conf.SMTP.Password,
		Pool:     pool.NewWorkerPool(2000),
	}
}