From ab530fa7a38f505e7f41c73ec4d765c7903a154e Mon Sep 17 00:00:00 2001
From: Sebastian Ohl <sebastian@ohl.name>
Date: Wed, 3 May 2023 16:55:59 +0200
Subject: [PATCH] adding mail notification bot for approvals

---
 bot/mail/mail.go | 123 +++++++++++++++++++++++++++++++++++++++++++++++
 cmd/keel/main.go |   1 +
 2 files changed, 124 insertions(+)
 create mode 100644 bot/mail/mail.go

diff --git a/bot/mail/mail.go b/bot/mail/mail.go
new file mode 100644
index 000000000..7301c6425
--- /dev/null
+++ b/bot/mail/mail.go
@@ -0,0 +1,123 @@
+package mail
+
+import (
+	"context"
+	"os"
+	"strconv"
+
+	"net/smtp"
+
+	"github.com/keel-hq/keel/bot"
+	"github.com/keel-hq/keel/constants"
+	"github.com/keel-hq/keel/types"
+
+	log "github.com/sirupsen/logrus"
+)
+
+
+// Bot - main mail notification bot container
+type Bot struct {
+	from       string
+	to         string
+	smtpServer string
+	smtpPort   int
+	smtpUser   string
+	smtpPass   string
+
+
+	ctx                context.Context
+}
+
+func init() {
+	bot.RegisterBot("mail", &Bot{})
+}
+
+func (b *Bot) Configure(approvalsRespCh chan *bot.ApprovalResponse, botMessagesChannel chan *bot.BotMessage) bool {
+	// Server, from and to are mandatory
+	if os.Getenv(constants.EnvMailSmtpServer) == "" ||
+	   	os.Getenv(constants.EnvMailFrom) != "" ||
+		os.Getenv(constants.EnvMailTo) != "" {
+		b.smtpServer = os.Getenv(constants.EnvMailSmtpServer)
+		b.from = os.Getenv(constants.EnvMailFrom)
+		b.to = os.Getenv(constants.EnvMailTo)
+
+		// Port, user and pass are optional
+		if os.Getenv(constants.EnvMailSmtpPort) != "" {
+			port, err := strconv.Atoi(os.Getenv(constants.EnvMailSmtpPort))
+			if err != nil {
+				log.WithFields(log.Fields{
+					"name": "mail",
+				}).Warn("bot.mail.Configure(): invalid SMTP port number")
+				return false
+			}
+			b.smtpPort = port
+		} else {
+			b.smtpPort = 25
+		}
+		if os.Getenv(constants.EnvMailSmtpUser) != "" {
+			b.smtpUser = os.Getenv(constants.EnvMailSmtpUser)
+		}
+		if os.Getenv(constants.EnvMailSmtpPass) != "" {
+			b.smtpPass = os.Getenv(constants.EnvMailSmtpPass)
+		}
+		
+		log.WithFields(log.Fields{
+			"name": "mail",
+		}).Info("bot.mail.Configure():: mail box configured")
+		
+		return true;
+	}
+	log.Info("bot.mail.Configure(): mail bot not configured")
+	return false
+}
+
+// Start - start bot
+func (b *Bot) Start(ctx context.Context) error {
+	// setting root context
+	b.ctx = ctx
+
+	return nil
+}
+
+func (b *Bot) postMessage(title, message string) error {
+	log.Info("bot.mail.postMessage(): post a message " + message)
+	body := message
+	msg := "From: " + b.from + "\n" +
+		"To: " + b.to + "\n" +
+		"Subject: Keel notification " + title + "\n\n" +
+		body
+
+	// Support only plain auth
+	var auth smtp.Auth = nil
+	if b.smtpUser != "" {
+		auth = smtp.PlainAuth(
+			"",
+			b.smtpUser,
+			b.smtpPass,
+			b.smtpServer,
+		)
+	}
+
+	err := smtp.SendMail(b.smtpServer+":"+strconv.Itoa(b.smtpPort), auth, b.from, []string{b.to}, []byte(msg))
+	if err != nil {
+		log.WithFields(log.Fields{
+			"error": err,
+		}).Error("extension.notification.mail: failed to send notification")
+	}
+	
+	return err
+}
+
+func (b *Bot) Respond(text string, channel string) {
+}
+
+// Request - request approval
+func (b *Bot) RequestApproval(req *types.Approval) error {
+	return b.postMessage(
+		"Approval required",
+		req.Message)
+}
+
+func (b *Bot) ReplyToApproval(approval *types.Approval) error {
+	return nil
+}
diff --git a/cmd/keel/main.go b/cmd/keel/main.go
index 2cbec24a7..9d5a28557 100644
--- a/cmd/keel/main.go
+++ b/cmd/keel/main.go
@@ -54,6 +54,7 @@ import (
 	// bots
 	_ "github.com/keel-hq/keel/bot/hipchat"
 	_ "github.com/keel-hq/keel/bot/slack"
+	_ "github.com/keel-hq/keel/bot/mail"
 
 	log "github.com/sirupsen/logrus"
 	// importing to ensure correct dependencies