refactor(msg_gateway): restructure and rename message_gateway aligned with custom_example

backend/plugins/domain/msg_gateway/push/email.go

@@ -0,0 +1,78 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package push
+
+import (
+	pkgmail "Wavelet/pkg/mail"
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"strconv"
+)
+
+func init() {
+	Register("email", &EmailPusher{})
+}
+
+// EmailPusher 基于 pkg/mail 的 SMTP 邮件推送实现
+type EmailPusher struct{}
+
+// Send 发送邮件
+func (p *EmailPusher) Send(ctx context.Context, cfg Config, target string, body map[string]any, _ string, ext map[string]any) (string, error) {
+	if cfg.URL == "" || cfg.Key == "" || cfg.Secret == "" {
+		return "", errors.New("email: SMTP configuration (url, key, secret) is incomplete")
+	}
+	if target == "" {
+		return "", errors.New("email: target email address is required")
+	}
+
+	title := bodyTitle(body)
+	content := bodyContent(body, "<p><b>%s</b>: %v</p>", "")
+
+	fromName := "System Notification"
+	if ext != nil {
+		if fn, ok := ext["from_name"].(string); ok && fn != "" {
+			fromName = fn
+		}
+	}
+
+	htmlBody := fmt.Sprintf(`<html><body><h2>%s</h2><div>%s</div></body></html>`, title, content)
+
+	host, portStr, err := net.SplitHostPort(cfg.URL)
+	port := 25
+	if err != nil {
+		host = cfg.URL
+	} else if p, err := strconv.Atoi(portStr); err == nil && p > 0 {
+		port = p
+	}
+
+	mailCfg := pkgmail.Config{
+		Host:     host,
+		Port:     port,
+		Username: cfg.Key,
+		Password: cfg.Secret,
+		FromName: fromName,
+	}
+
+	if err := pkgmail.SendMail(ctx, mailCfg, target, title, htmlBody); err != nil {
+		return "", fmt.Errorf("email: send smtp mail failed: %w", err)
+	}
+
+	return "", nil
+}
+
+// ValidateConfig 校验邮件 SMTP 配置
+func (p *EmailPusher) ValidateConfig(cfg Config) error {
+	if cfg.URL == "" {
+		return errors.New("SMTP host:port is required")
+	}
+	if cfg.Key == "" {
+		return errors.New("SMTP username is required")
+	}
+	if cfg.Secret == "" {
+		return errors.New("SMTP password is required")
+	}
+	return nil
+}