Deposit tokens

Token Deposit Process

Depositing tokens into an airdrop vault requires setting up the PDA's token account and transferring tokens from your wallet. This is a two-instruction process:

Create the vault's ATA (if it doesn't exist)
Transfer tokens to the vault

1. Find Required PDAs

import { findAssociatedTokenPda, TOKEN_PROGRAM_ADDRESS } from "@solana-program/token";

// Find the airdrop's vault  
const [vault, vaultBump] = await findAssociatedTokenPda({
  owner: airdropPda,
  mint: mint,
  tokenProgram: TOKEN_PROGRAM_ADDRESS,
});

// Find your source token account
const [sourceTokenAccount] = await findAssociatedTokenPda({
  owner: client.wallet.address,
  mint: mint,
  tokenProgram: TOKEN_PROGRAM_ADDRESS,
});

Locate the token accounts for both your wallet and the airdrop vault

2. Create Vault ATA (If Needed)

import { getCreateAssociatedTokenIdempotentInstructionAsync } from "@solana-program/token";

const vaultATACreateInst = await getCreateAssociatedTokenIdempotentInstructionAsync({
  ata: vault,
  mint: mint,
  payer: client.wallet,
  owner: airdropPda,
});

Idempotent operation that only creates if account doesn't exist

3. Get Deposit Instruction

import { getDepositTokensInstruction } from "@dropsy/airdrop";

const instruction = getDepositTokensInstruction({
  sourceTokenAccount,  // wallet ATA for the mint 
  vault,    //  airdrop ATA for the mint 
  mint,    // mint address 
  airdrop: airdropPda,    //airdrop pda address
  tokenProgram: TOKEN_PROGRAM_ADDRESS, // or  token 2022 address 
  authority: client.wallet,  // the airdrop authority 
  amount: 500000n, // Amount in token base units (not decimals)
});

Build the instruction to move tokens into the airdrop vault

4. Build Transaction

const transactionMessage = await createTransactionMessageFromInstructions(
  client.rpc,
  client.wallet,
  [vaultATACreateInst, instruction] // Order matters - create before transfer
);

const signedTransaction = await signTransactionMessageWithSigners(transactionMessage);

Create a single Transaction from both instructions

Send and Confirm Transaction

await client.sendAndConfirmTransaction(signedTransaction, { commitment: "confirmed" });
const signature = getSignatureFromTransaction(signedTransaction);

console.log("signature:", signature);

Submits the signed transaction to the network and waits for confirmation.

Critical Details

Token Decimals: The amount must be in base units (e.g., for 6-decimal token: 1 token = 1,000,000 units)
ATA Creation: The idempotent creation ensures the transaction won't fail if the ATA already exists
Order Matters: Always put the ATA creation instruction before the transfer

Verification

After deposit, verify the vault balance matches your expected amount:

const vaultBalance = await client.rpc.getTokenAccountBalance(vault).send();
console.log("Vault balance:", vaultBalance.value.amount);