fix(seo): sitemap全是undefined、域名写错；固定Node 22构建

- sitemap返回的是字符串数组，Next.js要的是{url}对象，所以每条都是undefined；
  同时改成收全部嵌套教程页（原来只取第一层目录）
- og:url、JSON-LD、sitemap、robots里的域名写成了别人家的codewithai.com，统一改成www.coderwithai.top
- 教程页加canonical，www和裸域都能打开时收口到www
- Vercel已停止支持Node 20，项目设置还是20.x，构建直接失败；用engines固定22.x（同Bookai做法）

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: alchaincyf

app/[language]/[...tutorial]/page.tsx

@@ -28,14 +28,18 @@ export async function generateMetadata(
     title,
     description: metadata.description,
     keywords: metadata.keywords,
+    alternates: {
+      // www 和裸域都能打开，用 canonical 收口到 www
+      canonical: `https://www.coderwithai.top/${language}/${tutorialPath}`,
+    },
     openGraph: {
       title,
       description: metadata.description,
-      url: `https://www.codewithai.com/${language}/${tutorialPath}`,
+      url: `https://www.coderwithai.top/${language}/${tutorialPath}`,
       siteName: 'CoderWithAI',
       images: [
         {
-          url: metadata.image || 'https://www.codewithai.com/images/default-og-image.jpg',
+          url: metadata.image || 'https://www.coderwithai.top/images/default-og-image.jpg',
           width: 1200,
           height: 630,
         },
@@ -48,7 +52,7 @@ export async function generateMetadata(
       card: 'summary_large_image',
       title,
       description: metadata.description,
-      images: [metadata.image || 'https://www.codewithai.com/images/default-twitter-image.jpg'],
+      images: [metadata.image || 'https://www.coderwithai.top/images/default-twitter-image.jpg'],
     },
   }
 }

app/layout.tsx

@@ -29,11 +29,11 @@ export const metadata: Metadata = {
   openGraph: {
     title: "CoderWithAI - 学习编程的最佳资源",
     description: "全面的编程教程和交互式学习平台",
-    url: "https://www.codewithai.com",
+    url: "https://www.coderwithai.top",
     siteName: "CoderWithAI",
     images: [
       {
-        url: "https://www.codewithai.com/images/og-image.jpg",
+        url: "https://www.coderwithai.top/images/og-image.jpg",
         width: 1200,
         height: 630,
       },
@@ -45,7 +45,7 @@ export const metadata: Metadata = {
     card: "summary_large_image",
     title: "CoderWithAI - 学习编程的最佳资源",
     description: "全面的编程教程和交互式学习平台",
-    images: ["https://www.codewithai.com/images/twitter-image.jpg"],
+    images: ["https://www.coderwithai.top/images/twitter-image.jpg"],
   },
 };
 
@@ -84,11 +84,11 @@ export default async function RootLayout({
               "@context": "https://schema.org",
               "@type": "WebSite",
               "name": "CoderWithAI",
-              "url": "https://www.codewithai.com",
+              "url": "https://www.coderwithai.top",
               "description": "CoderWithAI 提供全面的编程教程，涵盖多种编程语言和框架。通过我们的交互式学习平台，提升您的编程技能。",
               "potentialAction": {
                 "@type": "SearchAction",
-                "target": "https://www.codewithai.com/search?q={search_term_string}",
+                "target": "https://www.coderwithai.top/search?q={search_term_string}",
                 "query-input": "required name=search_term_string"
               }
             }

app/sitemap.ts

@@ -1,18 +1,30 @@
-import { getAvailableLanguages, getTutorials } from "@/lib/tutorials";
+import type { MetadataRoute } from "next";
+import { getAvailableLanguages, getTutorials, Tutorial } from "@/lib/tutorials";
 
-export default async function sitemap() {
-  const baseUrl = "https://www.codewithai.com";
-  const languages = await getAvailableLanguages();
+const baseUrl = "https://www.coderwithai.top";
+
+// 教程是按目录嵌套的：目录本身不是页面，只收叶子上的 .md 页面
+function collectPaths(items: Tutorial[], out: string[]) {
+  for (const t of items) {
+    if (t.items) collectPaths(t.items, out);
+    else out.push(t.path);
+  }
+}
 
-  const urls: string[] = [];
+const encodePath = (p: string) => p.split("/").map(encodeURIComponent).join("/");
+
+export default async function sitemap(): Promise<MetadataRoute.Sitemap> {
+  const languages = await getAvailableLanguages();
+  const entries: MetadataRoute.Sitemap = [{ url: baseUrl }];
 
   for (const lang of languages) {
-    const tutorials = await getTutorials(lang);
-    urls.push(`${baseUrl}/${lang}`);
-    tutorials.forEach((tutorial) => {
-      urls.push(`${baseUrl}/${lang}/${tutorial.path}`);
-    });
+    entries.push({ url: `${baseUrl}/${encodeURIComponent(lang)}` });
+    const paths: string[] = [];
+    collectPaths(await getTutorials(lang), paths);
+    for (const p of paths) {
+      entries.push({ url: `${baseUrl}/${encodeURIComponent(lang)}/${encodePath(p)}` });
+    }
   }
 
-  return urls;
-}
+  return entries;
+}

next.config.js

@@ -46,7 +46,7 @@ const nextConfig = {
     ];
   },
   images: {
-    domains: ['www.codewithai.com'], // 添加你的图片域名
+    domains: ['www.coderwithai.top'], // 添加你的图片域名
     unoptimized: true,
   },
 };

package.json

@@ -47,5 +47,8 @@
     "postcss": "^8",
     "tailwindcss": "^3.4.1",
     "typescript": "^5"
+  },
+  "engines": {
+    "node": "22.x"
   }
 }

public/robots.txt

@@ -1,4 +1,4 @@
 User-agent: *
 Allow: /
 
-Sitemap: https://www.codewithai.com/sitemap.xml
+Sitemap: https://www.coderwithai.top/sitemap.xml