How to sign a Solana Raydium swap? - rust

Question

I am getting a NotEnoughSigners error using amm_instruction::swap_base_in() for Raydium swap in Solana (https://github.com/raydium-io/raydium-contract-instructions). What am I doing wrong here? As far as I can tell, one signer is required and one is being submitted, but I get a NotEnoughSigners error.
// pubkey
use std::{str::FromStr};
use solana_program::{pubkey, pubkey::Pubkey};
// rpc
use solana_client::rpc_client::RpcClient;
mod amm_instruction;
fn main() {
// pool info
let program_id: Pubkey = pubkey!("675kPX9MHTjS2zt1qfr1NYHuzeLXfQM9H24wFSUt1Mp8");
let amm_id: Pubkey = pubkey!("58oQChx4yWmvKdwLLZzBi4ChoCc2fqCUWBkwMihLYQo2");
let amm_authority: Pubkey = pubkey!("5Q544fKrFoe6tsEbD7S8EmxGTJYAKtTVhAW5Q5pge4j1");
let amm_open_orders: Pubkey = pubkey!("HRk9CMrpq7Jn9sh7mzxE8CChHG8dneX9p475QKz4Fsfc");
let amm_target_orders: Pubkey = pubkey!("CZza3Ej4Mc58MnxWA385itCC9jCo3L1D7zc3LKy1bZMR");
let pool_coin_token_account: Pubkey = pubkey!("DQyrAcCrDXQ7NeoqGgDCZwBvWDcYmFCjSb9JtteuvPpz");
let pool_pc_token_account: Pubkey = pubkey!("HLmqeL62xR1QoZ1HKKbXRrdN1p3phKpxRMb2VVopvBBz");
let serum_program_id: Pubkey = pubkey!("9xQeWvG816bUx9EPjHmaT23yvVM2ZWbrrpZb9PusVFin");
let serum_market: Pubkey = pubkey!("9wFFyRfZBsuAha4YcuxcXLKwMxJR43S7fPfQLusDBzvT");
let serum_bids: Pubkey = pubkey!("14ivtgssEBoBjuZJtSAPKYgpUK7DmnSwuPMqJoVTSgKJ");
let serum_asks: Pubkey = pubkey!("CEQdAFKdycHugujQg9k2wbmxjcpdYZyVLfV9WerTnafJ");
let serum_event_queue: Pubkey = pubkey!("5KKsLVU6TcbVDK4BS6K1DGDxnh4Q9xjYJ8XaDCG5t8ht");
let serum_coin_vault_account: Pubkey = pubkey!("36c6YqAwyGKQG66XEp2dJc5JqjaBNv7sVghEtJv4c7u6");
let serum_pc_vault_account: Pubkey = pubkey!("8CFo8bL8mZQK8abbFyypFMwEDd8tVJjHTTojMLgQTUSZ");
let serum_vault_signer: Pubkey = pubkey!("F8Vyqk3unwxkXukZFQeYyGmFfTG3CAX4v24iyrjEYBJV");
let uer_source_token_account: Pubkey = pubkey!("AgzZJAiniqwX4MAkf7KGuza4oYk5XNBHUZ4XZeca7osC");
let uer_destination_token_account: Pubkey = pubkey!("ENJH5ho47pbHmMcoerGtRywQpkcbtWtnCfsKdHesf5E5");
let user_source_owner: Pubkey = pubkey!("FBH3xoEVNF85pkmpfsgevyTW9ewtL2M1xuHzJwaxdLm5");
let amount_in: u64 = 1_000_000;
let minimum_amount_out: u64 = 10_321_182;
// connect to cluster
//let url = "https://api.mainnet-beta.solana.com".to_string();
let url = "https://api.devnet.solana.com".to_string();
let rpc_client = RpcClient::new(url);
let latest_blockhash = rpc_client.get_latest_blockhash().unwrap();
let alice = solana_sdk::signer::keypair::read_keypair_file("/Users/Me/.config/solana/id.json").unwrap();
let swap_instructions = amm_instruction::swap_base_in(
&program_id,
&amm_id,
&amm_authority,
&amm_open_orders,
&amm_target_orders,
&pool_coin_token_account,
&pool_pc_token_account,
&serum_program_id,
&serum_market,
&serum_bids,
&serum_asks,
&serum_event_queue,
&serum_coin_vault_account,
&serum_pc_vault_account,
&serum_vault_signer,
&uer_source_token_account,
&uer_destination_token_account,
&user_source_owner,
amount_in,
minimum_amount_out
).unwrap();
let payer: Option<Pubkey> = Some(solana_program::pubkey::Pubkey::from_str("5C8rbEJUuLR2nTkEqiyjzmyBtxAiseS2Aoq7YU3c8cgL").unwrap());
let tx = solana_sdk::transaction::Transaction::new_signed_with_payer(&[swap_instructions], payer.as_ref(), &[&alice], latest_blockhash);
let signature = rpc_client.send_and_confirm_transaction(&tx);
println!("swap: {:?}",signature);
}

Answer 1

If you look at the code that you linked, you'll see that this instruction expects only one signature from user_source_owner: https://github.com/raydium-io/raydium-contract-instructions/blob/cbd7affe245166f7baceb7e68d123220e0fcd331/amm_instruction.rs#L594
This means that your transaction must be declared as:
let payer = Keypair::from_bytes(<INSERT_BYTES_HERE>); // this must be a some Signer in order to be declared as a payer, so use whichever method you need to get that keypair
let user_source_owner = Keypair::form_bytes(<PUT_BYTES_HERE>); // same here
let tx = solana_sdk::transaction::Transaction::new_signed_with_payer(&[swap_instructions], Some(&payer.pubkey()), &[&payer, &user_source_owner], latest_blockhash);