feat: add a sitemap

Author: recurser

pages/sitemap.xml.tsx

@@ -0,0 +1,62 @@
+import { isEmpty, kebabCase } from 'lodash'
+import { GetServerSideProps } from 'next'
+
+import * as converterModule from '@lib/converters'
+import type { Converter } from '@lib/converters'
+
+/**
+ * Placeholder - getServerSideProps() does all of the magic.
+ */
+// eslint-disable-next-line import/no-default-export
+export default function Sitemap() {
+  return null
+}
+
+/**
+ * Decide what domain we want to use for the sitemap.
+ */
+const baseUrl = isEmpty(process.env.NEXT_PUBLIC_ANALYTICS_DOMAIN)
+  ? 'https://localhost:3000'
+  : `https://${process.env.NEXT_PUBLIC_ANALYTICS_DOMAIN}`
+
+/**
+ * Build a list of page paths, by combining the static ones we
+ * know about, with a list of the dynamic converters.
+ */
+const staticPaths = ['', 'about', 'privacy', 'security', 'terms']
+const converters = Object.values(converterModule)
+const converterPaths = converters
+  .filter((cnv: Converter) => !cnv.isHidden)
+  .map((cnv: Converter) => kebabCase(cnv.id))
+  .map((id) => id.replace('java-script', 'javascript')) // Hyphenated looks non-standard.
+  .map((id) => id.replace(/-(\d)/g, '$1')) // Replace eg. /md-5-encoder with /md5-encoder.
+const allPaths = [...staticPaths, ...converterPaths].sort()
+
+/**
+ * Generates an XML sitemap.
+ *
+ * @param context - The request context.
+ */
+export const getServerSideProps: GetServerSideProps = async ({ res }) => {
+  const sitemap = `<?xml version="1.0" encoding="UTF-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+  ${allPaths
+    .map((path) => {
+      return `<url>
+    <loc>${baseUrl}/${path}</loc>
+    <lastmod>${new Date().toISOString()}</lastmod>
+    <changefreq>daily</changefreq>
+    <priority>1.0</priority>
+  </url>
+    `
+    })
+    .join('')}
+</urlset>
+`
+
+  res.setHeader('Content-Type', 'text/xml')
+  res.write(sitemap)
+  res.end()
+
+  return { props: {} }
+}