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后端 Go+Gin：认证/CSRF/限流、板块、帖子、评论、点赞、通知、用户资料、置顶推荐；前端 Next.js 16：发帖/编辑/删除、搜索、分页、点赞、通知中心、设置；基础设施 docker-compose 与配置模板；添加 .gitignore 与专有许可证（保留所有权利）

backend/handler/seo.go

@@ -0,0 +1,79 @@
+package handler
+
+import (
+	"encoding/xml"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/freefire/jiang13-bbs/model"
+	"github.com/gin-gonic/gin"
+)
+
+const siteBaseURL = "http://localhost:3000"
+
+// RobotsTxt robots.txt
+func (h *Handlers) RobotsTxt(c *gin.Context) {
+	content := fmt.Sprintf(`User-agent: *
+Allow: /
+Sitemap: %s/sitemap.xml
+`, siteBaseURL)
+	c.String(http.StatusOK, content)
+}
+
+// SitemapXML 生成 sitemap
+func (h *Handlers) SitemapXML(c *gin.Context) {
+	type urlEntry struct {
+		Loc        string `xml:"loc"`
+		Lastmod    string `xml:"lastmod"`
+		Changefreq string `xml:"changefreq"`
+		Priority   string `xml:"priority"`
+	}
+	type urlset struct {
+		XMLName xml.Name   `xml:"urlset"`
+		Xmlns   string     `xml:"xmlns,attr"`
+		URLs    []urlEntry `xml:"url"`
+	}
+
+	now := time.Now().Format("2006-01-02")
+	entries := []urlEntry{
+		{Loc: siteBaseURL + "/", Lastmod: now, Changefreq: "daily", Priority: "1.0"},
+	}
+
+	// 板块页
+	var boards []model.Board
+	model.DB.Find(&boards)
+	for _, b := range boards {
+		entries = append(entries, urlEntry{
+			Loc:        fmt.Sprintf("%s/board/%d", siteBaseURL, b.ID),
+			Lastmod:    now,
+			Changefreq: "daily",
+			Priority:   "0.8",
+		})
+	}
+
+	// 帖子详情页
+	var posts []model.Post
+	model.DB.Where("status = ?", model.ContentStatusPublished).
+		Order("created_at DESC").Limit(1000).Find(&posts)
+	for _, p := range posts {
+		entries = append(entries, urlEntry{
+			Loc:        fmt.Sprintf("%s/post/%d", siteBaseURL, p.ID),
+			Lastmod:    p.UpdatedAt.Format("2006-01-02"),
+			Changefreq: "weekly",
+			Priority:   "0.6",
+		})
+	}
+
+	us := urlset{
+		Xmlns: "http://www.sitemaps.org/schemas/sitemap/0.9",
+		URLs:  entries,
+	}
+	output, err := xml.MarshalIndent(us, "", "  ")
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	c.Header("Content-Type", "application/xml")
+	c.String(http.StatusOK, xml.Header+string(output))
+}