feat: Add support for sending emails

cmd/email.go

@@ -0,0 +1,127 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strings"
+
+	"github.com/nikoksr/notify"
+	"github.com/nikoksr/notify/service/mail"
+	"github.com/urfave/cli/v2"
+)
+
+type email struct {
+	SenderAddress   string
+	Password        string
+	Host            string
+	ReceiverAddress string
+	Subject         string
+	Message         string
+	Port            string
+	Identity        string
+}
+
+func SendToEmail() *cli.Command {
+	var emailOpts email
+	return &cli.Command{
+		Name:  "email",
+		Usage: "Send an email",
+		Description: `Email uses username  & password to authenticate for sending emails.
+SMTP hostname i.e smtp.gmail.com and port i.e (587) should be provided as well for the server.
+Multiple email ids can be used separated by comma ',' as receiver email address.
+All configuration options are also available via environment variables.`,
+		UsageText: "pingme email --pass '123456' --sender 'abc@email.com' --rec 'xyz@example.com' " +
+			"--msg 'some message' --sub 'email subject' --host 'smtp.gmail.com' --port '587'",
+		Flags: []cli.Flag{
+			&cli.StringFlag{
+				Destination: &emailOpts.Password,
+				Name:        "pass",
+				Required:    true,
+				Aliases:     []string{"p"},
+				Usage:       "Password of email address, use environment variable",
+				EnvVars:     []string{"EMAIL_PASSWORD"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.ReceiverAddress,
+				Name:        "rec",
+				Aliases:     []string{"r"},
+				Required:    true,
+				Usage:       "Receiver email address, if multiple separate with ','",
+				EnvVars:     []string{"EMAIL_RECEIVER"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.SenderAddress,
+				Name:        "sender",
+				Aliases:     []string{"s"},
+				Required:    true,
+				Usage:       "Senders email address",
+				EnvVars:     []string{"EMAIL_SENDER"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.Identity,
+				Name:        "identity",
+				Aliases:     []string{"idn"},
+				Value:       "",
+				Usage:       "Senders email Identity if any",
+				EnvVars:     []string{"EMAIL_IDENTITY"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.Host,
+				Name:        "host",
+				Aliases:     []string{"ho"},
+				Value:       "smtp.gmail.com",
+				Usage:       "SMTP Host",
+				EnvVars:     []string{"EMAIL_HOST"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.Port,
+				Name:        "port",
+				Value:       "587",
+				Aliases:     []string{"po"},
+				Usage:       "SMTP Port",
+				EnvVars:     []string{"EMAIL_PORT"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.Message,
+				Name:        "msg",
+				Usage:       "Message content",
+				Aliases:     []string{"m"},
+				EnvVars:     []string{"EMAIL_MESSAGE"},
+			},
+			&cli.StringFlag{
+				Destination: &emailOpts.Subject,
+				Name:        "sub",
+				Value:       TimeValue,
+				Usage:       "Subject of the email",
+				EnvVars:     []string{"EMAIL_SUBJECT"},
+			},
+		},
+		Action: func(ctx *cli.Context) error {
+			notifier := notify.New()
+			emailSvc := mail.New(emailOpts.SenderAddress, emailOpts.Host+":"+emailOpts.Port)
+			emailSvc.AuthenticateSMTP(emailOpts.Identity, emailOpts.SenderAddress, emailOpts.Password, emailOpts.Host)
+
+			chn := strings.Split(emailOpts.ReceiverAddress, ",")
+			for _, v := range chn {
+				if len(v) <= 0 {
+					return fmt.Errorf(EmptyChannel)
+				}
+
+				emailSvc.AddReceivers(v)
+			}
+
+			notifier.UseServices(emailSvc)
+
+			if err := notifier.Send(
+				context.Background(),
+				emailOpts.Subject,
+				emailOpts.Message,
+			); err != nil {
+				return err
+			}
+			log.Println("Successfully sent!")
+			return nil
+		},
+	}
+}