feat: cookbook example for working with relayer

packages/cookbook/transactions/meta-transaction-relayer.js

@@ -0,0 +1,50 @@
+const { Account } = require('@near-js/accounts');
+const { UnencryptedFileSystemKeyStore } = require('@near-js/keystores-node');
+const { JsonRpcProvider } = require('@near-js/providers');
+const { InMemorySigner } = require('@near-js/signers');
+const { actionCreators } = require('@near-js/transactions');
+const BN = require('bn.js');
+const os = require('os');
+const path = require('path');
+
+const { transfer } = actionCreators;
+
+async function sendNearThroughRelayer({ amount, receiverId, senderAccount }) {
+    const response = await senderAccount.signAndSendSignedDelegate({
+        actions: [transfer(amount)],
+        receiverId,
+        relayerUrl: 'https://relayer.org/relay',
+    });
+
+    console.log(response);
+    return response;
+}
+
+module.exports = {
+    sendNearThroughRelayer,
+};
+
+if (require.main === module) {
+    (async function () {
+        const networkId = 'testnet';
+        const provider = new JsonRpcProvider({ url: 'https://rpc.testnet.near.org' });
+
+        const CREDENTIALS_DIR = '.near-credentials';
+        const credentialsPath = path.join(os.homedir(), CREDENTIALS_DIR);
+
+        const RECEIVER_ACCOUNT_ID = 'receiver.testnet'; // the ultimate recipient of the meta transaction execution
+        const SENDER_ACCOUNT_ID = 'sender.testnet';     // the account requesting the transaction be executed
+
+        const senderAccount = new Account({
+            networkId,
+            provider,
+            signer: new InMemorySigner(new UnencryptedFileSystemKeyStore(credentialsPath))
+        }, SENDER_ACCOUNT_ID);
+
+        await sendNearThroughRelayer({
+            amount: new BN('1000000000'),
+            receiverId: RECEIVER_ACCOUNT_ID,
+            senderAccount,
+        });
+    }());
+}