Send Tokens to a Contract

Command Line Interface

When you execute a message, a user can also pass through a flag which sends funds from their account to the contract to do logic. You can check if a user sends any funds in your contract's execute endpoint with the info.funds array of Coins sent by the user. These funds then get added to the contracts balance just like any other account. So it is up to you as the developer to ensure to save how many funds each user has sent via a BTreeMap or other object storage in state (if they can redeem funds back at a later time).

To send funds to a contract with some arbitrary endpoint, you use the --amount flag.

junod tx wasm execute CONTRACT '{"some_endpoint":{}}' --amount 1000000ujuno

If the "some_endpoint" execute errors on the contract, the funds will remain in the users account.

Typescript

import type {Coin} from "@cosmjs/stargate"
import { SigningStargateClient, StargateClient, type StdFee } from '@cosmjs/stargate';

import type { OfflineAminoSigner } from '@cosmjs/amino';
import type { OfflineDirectSigner } from '@cosmjs/proto-signing';

import { SigningCosmWasmClient } from '@cosmjs/cosmwasm-stargate';

let RPC = "https://rpc.juno.strange.love"

const get_wallet_for_chain = async (
    chain_id: string
): Promise<OfflineAminoSigner | OfflineDirectSigner> => {
	// open keplr
	const keplr = window as KeplrWindow;
	if (keplr === undefined) {			
		throw new Error('Keplr not found');
	}
	let signer = keplr.getOfflineSignerAuto;
	if (signer === undefined) {
		throw new Error('Keplr not found');
	}
	return signer(chain_id);
};

let wallet = await get_wallet_for_chain("juno-1");
let address = (await wallet.getAccounts())[0].address;

let from_client = await SigningCosmWasmClient.connectWithSigner(RPC, wallet, {
	prefix: "juno"
});

const msg = {"some_endpoint": {}}

let fee: StdFee = {
    amount: [{amount: "5000",denom: "ujuno"}],
    gas: "500000"
}

let send_amount: Coin = {
    amount: "100000",
    denom: "ujuno"
}

await from_client.execute(
	address,
	REVIEWS_CONTRACT_ADDRESS,
	msg,
	fee,
	"memo",
	send_amount,
).then((res) => {
    console.log(`Success @ height ${res.height}\n\nTxHash: ${res.transactionHash}`)
});

ts-codegen

The cosmology toolkit has some useful typescript tools for interacting with your smart contracts. The repo can be found at https://github.com/CosmWasm/ts-codegen, with setup and query tutorials in Query A Contract section of this documentation.

Here are some video tutorials:

• How to Execute a cosmwasm smart contract
• Advanced execution with a cosmwasm message composer