Git-Mirrors/xmr-btc-swap
1
0
Fork 0
mirror of https://github.com/comit-network/xmr-btc-swap.git synced 2025-12-15 08:38:58 -05:00
Code Issues Projects Releases Packages Wiki Activity

fix(monero): Conservative Monero fee for max giveable calcuation (#376)

Browse source 
Increased from 0.000016 XMR to 0.003 XMR
This commit is contained in:
Mohan 2025-06-04 16:32:32 +02:00 • committed by GitHub
parent 708dee16c9
commit b6bfc2e128
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 23 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

32
swap/src/monero.rs
View file

@ -90,8 +90,18 @@ pub struct PublicViewKey(PublicKey);
#[typeshare(serialized_as = "number")]
pub struct Amount(u64);
// Median tx fees on Monero as found here: https://www.monero.how/monero-transaction-fees, XMR 0.000_008 * 2 (to be on the safe side)
pub const MONERO_FEE: Amount = Amount::from_piconero(16_000_000);
// TX Fees on Monero can be found here:
// - https://www.monero.how/monero-transaction-fees
// - https://bitinfocharts.com/comparison/monero-transactionfees.html#1y
//
// In the last year the highest avg fee on any given day was around 0.00075 XMR
// We use a multiplier of 4x to stay safe
// 0.00075 XMR * 4 = 0.003 XMR (around $1 as of Jun. 4th 2025)
// We DO NOT use this fee to construct any transactions. It is only to **estimate** how much
// we need to reserve for the fee when determining our max giveable amount
// We use a VERY conservative value here to stay on the safe side. We want to avoid not being able
// to lock as much as we previously estimated.
pub const CONSERVATIVE_MONERO_FEE: Amount = Amount::from_piconero(3_000_000_000);
impl Amount {
pub const ZERO: Self = Self(0);
@ -124,7 +134,9 @@ impl Amount {
/// Calculate the maximum amount of Bitcoin that can be bought at a given
/// asking price for this amount of Monero including the median fee.
pub fn max_bitcoin_for_price(&self, ask_price: bitcoin::Amount) -> Option<bitcoin::Amount> {
let pico_minus_fee = self.as_piconero().saturating_sub(MONERO_FEE.as_piconero());
let pico_minus_fee = self
.as_piconero()
.saturating_sub(CONSERVATIVE_MONERO_FEE.as_piconero());
if pico_minus_fee == 0 {
return Some(bitcoin::Amount::ZERO);
@ -456,27 +468,27 @@ mod tests {
// then max BTC we can buy is μ
let ask = bitcoin::Amount::from_btc(1.0).unwrap();
let xmr = Amount::parse_monero("1.0").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("1.0").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(1.0).unwrap());
let xmr = Amount::parse_monero("0.5").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("0.5").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(0.5).unwrap());
let xmr = Amount::parse_monero("2.5").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("2.5").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(2.5).unwrap());
let xmr = Amount::parse_monero("420").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("420").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(420.0).unwrap());
let xmr = Amount::parse_monero("0.00001").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("0.00001").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(0.00001).unwrap());
@ -484,13 +496,13 @@ mod tests {
// other ask prices
let ask = bitcoin::Amount::from_btc(0.5).unwrap();
let xmr = Amount::parse_monero("2").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("2").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(1.0).unwrap());
let ask = bitcoin::Amount::from_btc(2.0).unwrap();
let xmr = Amount::parse_monero("1").unwrap() + MONERO_FEE;
let xmr = Amount::parse_monero("1").unwrap() + CONSERVATIVE_MONERO_FEE;
let btc = xmr.max_bitcoin_for_price(ask).unwrap();
assert_eq!(btc, bitcoin::Amount::from_btc(2.0).unwrap());

2
swap/src/network/swap_setup/alice.rs
View file

@ -77,7 +77,7 @@ impl WalletSnapshot {
Ok(Self {
balance,
lock_fee: monero::MONERO_FEE,
lock_fee: monero::CONSERVATIVE_MONERO_FEE,
redeem_address,
punish_address,
redeem_fee,