feat: add auto-generated sitemap

pages/sitemap.xml.tsx

@@ -0,0 +1,36 @@
+import React from 'react'
+
+import { SiteMap } from 'lib/types'
+import { host } from 'lib/config'
+import { getSiteMaps } from 'lib/get-site-maps'
+
+const createSitemap = (
+  siteMap: SiteMap
+) => `<?xml version="1.0" encoding="UTF-8"?>
+    <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+      <url>
+        <loc>${host}</loc>
+        <loc>${host}/</loc>
+      </url>
+
+      ${Object.keys(siteMap.canonicalPageMap)
+        .map((canonicalPagePath) =>
+          `
+            <url>
+              <loc>${host}/${canonicalPagePath}</loc>
+            </url>
+          `.trim()
+        )
+        .join('')}
+    </urlset>
+    `
+
+export default class Sitemap extends React.Component {
+  static async getInitialProps({ res }) {
+    const siteMaps = await getSiteMaps()
+
+    res.setHeader('Content-Type', 'text/xml')
+    res.write(createSitemap(siteMaps[0]))
+    res.end()
+  }
+}