Add branch-aware robots.txt

functions/robots.txt.ts

@@ -0,0 +1,67 @@
+export function onRequest(context: { env: { CF_PAGES_BRANCH?: string; }; }) {
+  const branch = context.env.CF_PAGES_BRANCH;
+  const isMain = branch === 'main';
+
+  const body = isMain
+    ? `# As a condition of accessing this website, you agree to abide by the following
+# content signals:
+
+# (a) If a content-signal = yes, you may collect content for the corresponding
+#     use.
+# (b) If a content-signal = no, you may not collect content for the
+#     corresponding use.
+# (c) If the website operator does not include a content signal for a
+#     corresponding use, the website operator neither grants nor restricts
+#     via content signal with respect to the corresponding use.
+
+# The content signals and their meanings are:
+
+# search:   building a search index and providing search results (e.g., returning
+#           hyperlinks and short excerpts from your website's contents). Search does not
+#           include providing AI-generated search summaries.
+# ai-input: inputting content into one or more AI models (e.g., retrieval
+#           augmented generation, grounding, or other real-time taking of content for
+#           generative AI search answers).
+# ai-train: training or fine-tuning AI models.
+
+# ANY RESTRICTIONS EXPRESSED VIA CONTENT SIGNALS ARE EXPRESS RESERVATIONS OF
+# RIGHTS UNDER ARTICLE 4 OF THE EUROPEAN UNION DIRECTIVE 2019/790 ON COPYRIGHT
+# AND RELATED RIGHTS IN THE DIGITAL SINGLE MARKET.
+
+User-agent: *
+Allow: /
+
+User-agent: Amazonbot
+Disallow: /
+
+User-agent: Applebot-Extended
+Disallow: /
+
+User-agent: Bytespider
+Disallow: /
+
+User-agent: CCBot
+Disallow: /
+
+User-agent: ClaudeBot
+Disallow: /
+
+User-agent: Google-Extended
+Disallow: /
+
+User-agent: GPTBot
+Disallow: /
+
+User-agent: meta-externalagent
+Disallow: /
+`
+    : `User-agent: *
+Disallow: /
+`;
+
+  return new Response(body + '\n', {
+    headers: {
+      'Content-Type': 'text/plain',
+    },
+  });
+}