first commit

server/internal/notify/email.go

@@ -0,0 +1,88 @@
+package notify
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net/smtp"
+	"strconv"
+	"strings"
+)
+
+type EmailNotifier struct{}
+
+func NewEmailNotifier() *EmailNotifier             { return &EmailNotifier{} }
+func (n *EmailNotifier) Type() string              { return "email" }
+func (n *EmailNotifier) SensitiveFields() []string { return []string{"password"} }
+
+func (n *EmailNotifier) Validate(config map[string]any) error {
+	host := strings.TrimSpace(asString(config["host"]))
+	port := asInt(config["port"])
+	from := strings.TrimSpace(asString(config["from"]))
+	to := strings.TrimSpace(asString(config["to"]))
+	if host == "" || port <= 0 || from == "" || to == "" {
+		return fmt.Errorf("email host/port/from/to are required")
+	}
+	return nil
+}
+
+func (n *EmailNotifier) Send(_ context.Context, config map[string]any, message Message) error {
+	if err := n.Validate(config); err != nil {
+		return err
+	}
+	host := strings.TrimSpace(asString(config["host"]))
+	port := asInt(config["port"])
+	username := strings.TrimSpace(asString(config["username"]))
+	password := strings.TrimSpace(asString(config["password"]))
+	from := strings.TrimSpace(asString(config["from"]))
+	toList := splitCommaValues(asString(config["to"]))
+	address := host + ":" + strconv.Itoa(port)
+	headers := []string{"From: " + from, "To: " + strings.Join(toList, ", "), "Subject: " + message.Title, "MIME-Version: 1.0", "Content-Type: text/plain; charset=UTF-8", "", message.Body}
+	var auth smtp.Auth
+	if username != "" {
+		auth = smtp.PlainAuth("", username, password, host)
+	}
+
+	rawMessage := []byte(strings.Join(headers, "\r\n"))
+
+	if port == 465 {
+		tlsConfig := &tls.Config{ServerName: host}
+		conn, err := tls.Dial("tcp", address, tlsConfig)
+		if err != nil {
+			return fmt.Errorf("dial tls for smtp port 465 failed: %w", err)
+		}
+		client, err := smtp.NewClient(conn, host)
+		if err != nil {
+			return fmt.Errorf("create smtp client over tls failed: %w", err)
+		}
+		defer client.Close()
+		if auth != nil {
+			if ok, _ := client.Extension("AUTH"); ok {
+				if err = client.Auth(auth); err != nil {
+					return fmt.Errorf("smtp auth failed: %w", err)
+				}
+			}
+		}
+		if err = client.Mail(from); err != nil {
+			return fmt.Errorf("smtp mail from failed: %w", err)
+		}
+		for _, toAddr := range toList {
+			if err = client.Rcpt(toAddr); err != nil {
+				return fmt.Errorf("smtp rcpt failed for %s: %w", toAddr, err)
+			}
+		}
+		writer, err := client.Data()
+		if err != nil {
+			return fmt.Errorf("smtp data failed: %w", err)
+		}
+		if _, err = writer.Write(rawMessage); err != nil {
+			return fmt.Errorf("smtp write message failed: %w", err)
+		}
+		if err = writer.Close(); err != nil {
+			return fmt.Errorf("smtp data close failed: %w", err)
+		}
+		return client.Quit()
+	}
+
+	return smtp.SendMail(address, auth, from, toList, rawMessage)
+}