Programmatically submit multiple transactions to a gnosis safe to be signed as one

gnosis-safe-multisend-submitter.js

// Extrapolated from https://github.com/gnosis/safe-core-sdk 

const ethers = require('ethers');
const { EthersAdapter } = require('@gnosis.pm/safe-core-sdk');
const Safe = require('@gnosis.pm/safe-core-sdk').default;

const SafeServiceClient = require('@gnosis.pm/safe-service-client').default;


const providerUrl = '....'; 
const provider = new ethers.providers.JsonRpcProvider(providerUrl);
const privateKey = '....';
const signer = new ethers.Wallet(privateKey, provider);

const ethAdapter = new EthersAdapter({
	ethers,
	signer,
});

(async function() {
	const safeAddress = '....';
	const safeSdk = await Safe.create({
		ethAdapter,
		safeAddress,
	});

	const transactions = [
		{
			to: '0x....',
			value: '0',
			data: '0x....',
		},
		{
			to: '0x...',
			value: '0',
			data: '0x...',
		},
	];
	const safeTransaction = await safeSdk.createTransaction(...transactions);
	const txHash = await safeSdk.getTransactionHash(safeTransaction);
	const signature = await safeSdk.signTransactionHash(txHash);

	const safeService = new SafeServiceClient('https://safe-transaction.gnosis.io');
	try {
		await safeService.proposeTransaction(safeAddress, safeTransaction.data, txHash, signature);

		console.log(
			'Submitted a batch of',
			transactions.length,
			'transactions to the safe',
			safeAddress
		);
	} catch (err) {
		console.log(require('util').inspect(err, true, null, true));
	}
})();