feat(help-center): expose public sitemap

internal/handler/api/v1/portal_handler.go

@@ -2,7 +2,9 @@ package v1
 
 import (
 	"encoding/json"
+	"html"
 	"net/http"
+	"os"
 	"strconv"
 	"strings"
 
@@ -43,6 +45,36 @@ func (h *PortalHandler) PublicGet(c *gin.Context) {
 	c.JSON(http.StatusOK, publicPortalPayload(portal))
 }
 
+// PublicSitemap returns the public help-center XML sitemap.
+// GET /hc/:slug/sitemap.xml
+func (h *PortalHandler) PublicSitemap(c *gin.Context) {
+	portal, ok := h.resolvePublicPortal(c)
+	if !ok {
+		return
+	}
+	baseURL := publicHelpCenterBaseURL(c, portal)
+
+	var b strings.Builder
+	b.WriteString("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
+	b.WriteString("<urlset xmlns=\"http://www.sitemaps.org/schemas/sitemap/0.9\">\n")
+	for i := range portal.Articles {
+		article := &portal.Articles[i]
+		if article.Status != string(model.ArticleStatusPublished) {
+			continue
+		}
+		b.WriteString("  <url>\n")
+		b.WriteString("    <loc>")
+		b.WriteString(html.EscapeString(baseURL + "/hc/" + portal.Slug + "/articles/" + article.Slug))
+		b.WriteString("</loc>\n")
+		b.WriteString("    <lastmod>")
+		b.WriteString(article.UpdatedAt.Format("2006-01-02"))
+		b.WriteString("</lastmod>\n")
+		b.WriteString("  </url>\n")
+	}
+	b.WriteString("</urlset>\n")
+	c.Data(http.StatusOK, "application/xml; charset=utf-8", []byte(b.String()))
+}
+
 // Create creates a new portal.
 // POST /api/v1/accounts/:account_id/portals
 func (h *PortalHandler) Create(c *gin.Context) {
@@ -270,6 +302,27 @@ func (h *PortalHandler) resolvePublicPortal(c *gin.Context) (*model.Portal, bool
 	return portal, true
 }
 
+func publicHelpCenterBaseURL(c *gin.Context, portal *model.Portal) string {
+	baseURL := ""
+	if portal != nil {
+		baseURL = strings.TrimSpace(portal.CustomDomain)
+	}
+	if baseURL == "" {
+		baseURL = strings.TrimSpace(os.Getenv("FRONTEND_URL"))
+	}
+	if baseURL == "" && c != nil && c.Request != nil {
+		baseURL = c.Request.Host
+	}
+	baseURL = strings.TrimRight(baseURL, "/")
+	if baseURL == "" {
+		baseURL = "localhost:3000"
+	}
+	if !strings.Contains(baseURL, "://") {
+		baseURL = "https://" + baseURL
+	}
+	return baseURL
+}
+
 func portalDefaultLocale(portal *model.Portal) string {
 	if portal == nil {
 		return "en"