feat(farcaster): enable offchain resolver to farcaster names #194

src/addressResolvers/farcaster.ts

@@ -0,0 +1,115 @@
+import { capture } from '@snapshot-labs/snapshot-sentry';
+import { graphQlCall, Address, Handle, FetchError, isSilencedError, isEvmAddress } from './utils';
+
+export const NAME = 'Farcaster';
+const FNAMES_API_URL = 'https://fnames.farcaster.xyz/transfers?name=';
+const NEYNAR_API_URL = 'https://api.neynar.com/v2/farcaster/user/';
+const API_KEY = 'NEYNAR_API_DOCS'; // add api key on .env
+
+interface User {
+  username: string;
+  verified_addresses: {
+    eth_addresses: string[];
+    sol_addresses: string[];
+  };
+  pfp_url: string;
+}
+
+interface UserDetails {
+  [address: string]: User[] | string;
+}
+
+async function fetchData(url, options = {}) {
+    const response = await fetch(url, { ...options, headers: { accept: 'application/json', api_key: API_KEY, ...options.headers } });
+    if (!response.ok) {
+        throw new Error(`Failed to fetch data from the API. Status: ${response.status}`);
+    }
+    return response.json();
+}
+
+export async function lookupAddresses(addresses) {
+    const results = {};
+    const addressesQuery = addresses.join(',');
+
+    try {
+        const url = `${NEYNAR_API_URL}bulk-by-address?addresses=${addressesQuery}`;
+        const userDetails = await fetchData(url, {
+            method: 'GET'
+        });
+
+        Object.entries(userDetails).forEach(([address, data]) => {
+          if (Array.isArray(data) && data.length > 0) {
+            const user = data[0];
+            if ('username' in user && 'verified_addresses' in user && 'pfp_url' in user) {
+              results[address] = {
+                username: user.username,
+                eth_addresses: user.verified_addresses.eth_addresses ?? [],
+                sol_addresses: user.verified_addresses.sol_addresses ?? [],
+                pfp_url: user.pfp_url
+              };
+            } else {
+              console.warn(`Incomplete user data for address: ${address}`);
+              results[address] = "Incomplete user data.";
+            }
+          } else {
+            results[address] = "No user found for this address.";
+          }
+        });
+
+        return results;
+    } catch (error) {
+        console.error(`Error fetching address details:`, error);
+        throw new Error(`Error fetching address details.`);
+    }
+}
+
+async function fetchUserDetailsByUsername(username) {
+    try {
+        const transferData = await fetchData(`${FNAMES_API_URL}${username}`);
+        if (transferData.transfers.length > 0) {
+            const fid = 197049; // using fid arbitrary to use neymar search api
+            const userDetails = await fetchData(
+              `${NEYNAR_API_URL}search?q=${username}&viewer_fid=${fid}`,
+              {
+                method: 'GET'
+              }
+            );
+            if (userDetails.result && userDetails.result.users.length > 0) {
+                const user = userDetails.result.users[0];
+                return {
+                    username: user.username,
+                    verified_addresses: {
+                        eth_addresses: user.verified_addresses.eth_addresses,
+                        sol_addresses: user.verified_addresses.sol_addresses
+                    },
+                    pfp: user.pfp.url
+                };
+            }
+        }
+    } catch (error) {
+        console.error(`Error fetching user details ${username}:`, error);
+        throw new FetchError(`Error fetching user details ${username}.`);
+    }
+    return null;
+}
+
+
+export async function resolveNames(handles) {
+    const results = {};
+
+    for (const handle of handles) {
+        const normalizedHandle = handle.includes('.fcast.id') ? handle.split('.fcast.id')[0] : handle;
+        const userDetails = await fetchUserDetailsByUsername(normalizedHandle);
+        if (userDetails) {
+            results[handle] = {
+                eth_addresses: userDetails.verified_addresses.eth_addresses,
+                sol_addresses: userDetails.verified_addresses.sol_addresses,
+                pfp_url: userDetails.pfp
+            };
+        } else {
+            results[handle] = "User not found or error searching for details.";
+        }
+    }
+
+    return results;
+}

test/integration/addressResolvers/farcaster.test.ts

@@ -0,0 +1,12 @@
+import { resolveNames, lookupAddresses } from '../../../src/addressResolvers/farcaster';
+import testAddressResolver from './helper';
+
+testAddressResolver({
+  name: 'Farcaster',
+  lookupAddresses,
+  resolveNames,
+  validAddress: '0xd1a8Dd23e356B9fAE27dF5DeF9ea025A602EC81e',
+  validDomain: 'codingsh.fcast.id',
+  blankAddress: '0x0000000000000000000000000000000000000000',
+  invalidDomains: ['domain.crypto', 'domain.eth', 'domain.com']
+});