bbgo/pkg/pricesolver/simple.go

120 lines
3.5 KiB
Go

package pricesolver
import (
"sync"
log "github.com/sirupsen/logrus"
"git.qtrade.icu/lychiyu/bbgo/pkg/fixedpoint"
"git.qtrade.icu/lychiyu/bbgo/pkg/types"
)
// SimplePriceSolver implements a map-structure-based price index
type SimplePriceSolver struct {
// symbolPrices stores the latest trade price by mapping symbol to price
symbolPrices map[string]fixedpoint.Value
markets types.MarketMap
// pricesByBase stores the prices by currency names as a 2-level map
// BTC -> USDT -> 48000.0
// BTC -> TWD -> 1536000
pricesByBase map[string]map[string]fixedpoint.Value
// pricesByQuote is for reversed pairs, like USDT/TWD or BNB/BTC
// the reason that we don't store the reverse pricing in the same map is:
// expression like (1/price) could produce precision issue since the data type is fixed-point, only 8 fraction numbers are supported.
pricesByQuote map[string]map[string]fixedpoint.Value
mu sync.Mutex
}
func NewSimplePriceResolver(markets types.MarketMap) *SimplePriceSolver {
return &SimplePriceSolver{
markets: markets,
symbolPrices: make(map[string]fixedpoint.Value),
pricesByBase: make(map[string]map[string]fixedpoint.Value),
pricesByQuote: make(map[string]map[string]fixedpoint.Value),
}
}
func (m *SimplePriceSolver) Update(symbol string, price fixedpoint.Value) {
m.mu.Lock()
defer m.mu.Unlock()
m.symbolPrices[symbol] = price
market, ok := m.markets[symbol]
if !ok {
log.Warnf("market info %s not found, unable to update price", symbol)
return
}
quoteMap, ok2 := m.pricesByBase[market.BaseCurrency]
if !ok2 {
quoteMap = make(map[string]fixedpoint.Value)
m.pricesByBase[market.BaseCurrency] = quoteMap
}
quoteMap[market.QuoteCurrency] = price
baseMap, ok3 := m.pricesByQuote[market.QuoteCurrency]
if !ok3 {
baseMap = make(map[string]fixedpoint.Value)
m.pricesByQuote[market.QuoteCurrency] = baseMap
}
baseMap[market.BaseCurrency] = price
}
func (m *SimplePriceSolver) UpdateFromTrade(trade types.Trade) {
m.Update(trade.Symbol, trade.Price)
}
func (m *SimplePriceSolver) inferencePrice(asset string, assetPrice fixedpoint.Value, preferredFiats ...string) (fixedpoint.Value, bool) {
// log.Infof("inferencePrice %s = %f", asset, assetPrice.Float64())
quotePrices, ok := m.pricesByBase[asset]
if ok {
for quote, price := range quotePrices {
for _, fiat := range preferredFiats {
if quote == fiat {
return price.Mul(assetPrice), true
}
}
}
for quote, price := range quotePrices {
if infPrice, ok := m.inferencePrice(quote, price.Mul(assetPrice), preferredFiats...); ok {
return infPrice, true
}
}
}
// for example, quote = TWD here, we can get a price map with:
// USDT: 32.0 (for USDT/TWD at 32.0)
basePrices, ok := m.pricesByQuote[asset]
if ok {
for base, basePrice := range basePrices {
// log.Infof("base %s @ %s", base, basePrice.String())
for _, fiat := range preferredFiats {
if base == fiat {
// log.Infof("ret %f / %f = %f", assetPrice.Float64(), basePrice.Float64(), assetPrice.Div(basePrice).Float64())
return assetPrice.Div(basePrice), true
}
}
}
for base, basePrice := range basePrices {
if infPrice, ok2 := m.inferencePrice(base, assetPrice.Div(basePrice), preferredFiats...); ok2 {
return infPrice, true
}
}
}
return fixedpoint.Zero, false
}
func (m *SimplePriceSolver) ResolvePrice(asset string, preferredFiats ...string) (fixedpoint.Value, bool) {
m.mu.Lock()
defer m.mu.Unlock()
return m.inferencePrice(asset, fixedpoint.One, preferredFiats...)
}