feat: use new opengraph functions

functions/_middleware.ts

@@ -0,0 +1,78 @@
+interface Env {}
+
+import { bech32 } from "./bech32";
+import { fromHex } from "./hex";
+
+interface NostrJson {
+  names: Record<string, string>;
+}
+
+const HOST = "snort.social";
+
+async function fetchNostrAddress(name: string, domain: string) {
+  try {
+    const res = await fetch(`https://${domain}/.well-known/nostr.json?name=${encodeURIComponent(name)}`, {
+      signal: AbortSignal.timeout(1000),
+    });
+    const data: NostrJson = await res.json();
+    const match = Object.keys(data.names).find(n => {
+      return n.toLowerCase() === name.toLowerCase();
+    });
+    return match ? data.names[match] : undefined;
+  } catch {
+    // ignored
+  }
+}
+
+export const onRequest: PagesFunction<Env> = async context => {
+  const u = new URL(context.request.url);
+
+  const prefixes = ["npub1", "nprofile1", "naddr1", "nevent1", "note1"];
+  const isEntityPath = () => {
+    return prefixes.some(
+      a => u.pathname.startsWith(`/${a}`) || u.pathname.startsWith(`/e/${a}`) || u.pathname.startsWith(`/p/${a}`),
+    );
+  };
+
+  const nostrAddress = u.pathname.match(/^\/([a-zA-Z0-9_]+)$/i);
+
+  const next = await context.next();
+  if (u.pathname != "/" && (isEntityPath() || nostrAddress)) {
+    try {
+      let id = nostrAddress ? nostrAddress[1] : u.pathname.split("/").at(-1);
+      if (nostrAddress) {
+        const pubkey = await fetchNostrAddress(id, HOST);
+        if (pubkey) {
+          id = bech32.encode("npub", bech32.toWords(fromHex(pubkey)));
+        } else {
+          return next;
+        }
+      }
+      const rsp = await fetch(
+        `http://nostr.api.v0l.io/api/v1/opengraph/${id}?canonical=${encodeURIComponent(`https://${HOST}/%s`)}`,
+        {
+          method: "POST",
+          body: await next.arrayBuffer(),
+          headers: {
+            "user-agent": `SnortFunctions/1.0 (https://${HOST})`,
+            "content-type": "text/html",
+            accept: "text/html",
+          },
+        },
+      );
+      if (rsp.ok) {
+        const body = await rsp.text();
+        if (body.length > 0) {
+          return new Response(body, {
+            headers: {
+              "content-type": "text/html",
+            },
+          });
+        }
+      }
+    } catch {
+      // ignore
+    }
+  }
+  return next;
+};