Switch to using @farcaster/frame-node for webhook parsing & validation

src/lib/jfs.ts

@@ -1,62 +0,0 @@
-import { ed25519 } from "@noble/curves/ed25519";
-import {
-  encodedJsonFarcasterSignatureSchema,
-  jsonFarcasterSignatureHeaderSchema,
-} from "@farcaster/frame-sdk";
-import { isSignerValid } from "~/lib/neynar";
-
-type VerifyJsonFarcasterSignatureResult =
-  | { success: false; error: unknown }
-  | { success: true; fid: number; payload: string };
-
-export async function verifyJsonFarcasterSignature(
-  data: unknown
-): Promise<VerifyJsonFarcasterSignatureResult> {
-  // Parse & decode
-  const body = encodedJsonFarcasterSignatureSchema.safeParse(data);
-  if (body.success === false) {
-    return { success: false, error: body.error.errors };
-  }
-
-  const headerData = JSON.parse(
-    Buffer.from(body.data.header, "base64url").toString("utf-8")
-  );
-  const header = jsonFarcasterSignatureHeaderSchema.safeParse(headerData);
-  if (header.success === false) {
-    return { success: false, error: header.error.errors };
-  }
-
-  const signature = Buffer.from(body.data.signature, "base64url");
-  if (signature.byteLength !== 64) {
-    return { success: false, error: "Invalid signature length" };
-  }
-
-  const fid = header.data.fid;
-  const key = header.data.key;
-
-  // Verify that the signer belongs to the FID
-  try {
-    const validSigner = await isSignerValid({
-      fid,
-      signerPublicKey: key,
-    });
-    if (!validSigner) {
-      return { success: false, error: "Invalid signer" };
-    }
-  } catch {
-    return { success: false, error: "Error verifying signer" };
-  }
-
-  const signedInput = new Uint8Array(
-    Buffer.from(body.data.header + "." + body.data.payload)
-  );
-
-  const keyBytes = Uint8Array.from(Buffer.from(key.slice(2), "hex"));
-
-  const verifyResult = ed25519.verify(signature, signedInput, keyBytes);
-  if (!verifyResult) {
-    return { success: false, error: "Invalid signature" };
-  }
-
-  return { success: true, fid, payload: body.data.payload };
-}

src/lib/neynar.ts

@@ -1,34 +0,0 @@
-const apiKey = process.env.NEYNAR_API_KEY || "";
-
-export async function isSignerValid({
-  fid,
-  signerPublicKey,
-}: {
-  fid: number;
-  signerPublicKey: string;
-}): Promise<boolean> {
-  const url = new URL("https://hub-api.neynar.com/v1/onChainSignersByFid");
-  url.searchParams.append("fid", fid.toString());
-
-  const response = await fetch(url, {
-    method: "GET",
-    headers: {
-      "x-api-key": apiKey,
-    },
-  });
-
-  if (response.status !== 200) {
-    throw new Error(await response.text());
-  }
-
-  const responseJson = await response.json();
-  const signerPublicKeyLC = signerPublicKey.toLowerCase();
-
-  const signerExists = responseJson.events.find(
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    (event: any) =>
-      event.signerEventBody.key.toLowerCase() === signerPublicKeyLC
-  );
-
-  return signerExists;
-}