import { createSlice } from '@reduxjs/toolkit'; import BigNumber from 'bignumber.js'; import log from 'loglevel'; import { addToken, addUnapprovedTransaction, fetchAndSetQuotes, forceUpdateMetamaskState, resetSwapsPostFetchState, setBackgroundSwapRouteState, setInitialGasEstimate, setSwapsErrorKey, setSwapsTxGasPrice, setApproveTxId, setTradeTxId, stopPollingForQuotes, updateAndApproveTx, updateTransaction, resetBackgroundSwapsState, setSwapsLiveness, setSelectedQuoteAggId, setSwapsTxGasLimit, cancelTx, } from '../../store/actions'; import { AWAITING_SWAP_ROUTE, BUILD_QUOTE_ROUTE, LOADING_QUOTES_ROUTE, SWAPS_ERROR_ROUTE, SWAPS_MAINTENANCE_ROUTE, } from '../../helpers/constants/routes'; import { fetchSwapsFeatureLiveness, fetchSwapsGasPrices, } from '../../pages/swaps/swaps.util'; import { calcGasTotal } from '../../pages/send/send.utils'; import { decimalToHex, getValueFromWeiHex, decGWEIToHexWEI, hexWEIToDecGWEI, } from '../../helpers/utils/conversions.util'; import { conversionLessThan } from '../../helpers/utils/conversion-util'; import { calcTokenAmount } from '../../helpers/utils/token-util'; import { getSelectedAccount, getTokenExchangeRates, getUSDConversionRate, getSwapsDefaultToken, getCurrentChainId, } from '../../selectors'; import { ERROR_FETCHING_QUOTES, QUOTES_NOT_AVAILABLE_ERROR, SWAP_FAILED_ERROR, SWAPS_FETCH_ORDER_CONFLICT, } from '../../../../shared/constants/swaps'; import { TRANSACTION_TYPES } from '../../../../shared/constants/transaction'; const GAS_PRICES_LOADING_STATES = { INITIAL: 'INITIAL', LOADING: 'LOADING', FAILED: 'FAILED', COMPLETED: 'COMPLETED', }; export const FALLBACK_GAS_MULTIPLIER = 1.5; const initialState = { aggregatorMetadata: null, approveTxId: null, balanceError: false, fetchingQuotes: false, fromToken: null, quotesFetchStartTime: null, topAssets: {}, toToken: null, customGas: { price: null, limit: null, loading: GAS_PRICES_LOADING_STATES.INITIAL, priceEstimates: {}, fallBackPrice: null, }, }; const slice = createSlice({ name: 'swaps', initialState, reducers: { clearSwapsState: () => initialState, navigatedBackToBuildQuote: (state) => { state.approveTxId = null; state.balanceError = false; state.fetchingQuotes = false; state.customGas.limit = null; state.customGas.price = null; }, retriedGetQuotes: (state) => { state.approveTxId = null; state.balanceError = false; state.fetchingQuotes = false; }, setAggregatorMetadata: (state, action) => { state.aggregatorMetadata = action.payload; }, setBalanceError: (state, action) => { state.balanceError = action.payload; }, setFetchingQuotes: (state, action) => { state.fetchingQuotes = action.payload; }, setFromToken: (state, action) => { state.fromToken = action.payload; }, setQuotesFetchStartTime: (state, action) => { state.quotesFetchStartTime = action.payload; }, setTopAssets: (state, action) => { state.topAssets = action.payload; }, setToToken: (state, action) => { state.toToken = action.payload; }, swapCustomGasModalClosed: (state) => { state.customGas.price = null; state.customGas.limit = null; }, swapCustomGasModalPriceEdited: (state, action) => { state.customGas.price = action.payload; }, swapCustomGasModalLimitEdited: (state, action) => { state.customGas.limit = action.payload; }, swapGasPriceEstimatesFetchStarted: (state) => { state.customGas.loading = GAS_PRICES_LOADING_STATES.LOADING; }, swapGasPriceEstimatesFetchFailed: (state) => { state.customGas.loading = GAS_PRICES_LOADING_STATES.FAILED; }, swapGasPriceEstimatesFetchCompleted: (state, action) => { state.customGas.priceEstimates = action.payload.priceEstimates; state.customGas.loading = GAS_PRICES_LOADING_STATES.COMPLETED; }, retrievedFallbackSwapsGasPrice: (state, action) => { state.customGas.fallBackPrice = action.payload; }, }, }); const { actions, reducer } = slice; export default reducer; // Selectors export const getAggregatorMetadata = (state) => state.swaps.aggregatorMetadata; export const getBalanceError = (state) => state.swaps.balanceError; export const getFromToken = (state) => state.swaps.fromToken; export const getTopAssets = (state) => state.swaps.topAssets; export const getToToken = (state) => state.swaps.toToken; export const getFetchingQuotes = (state) => state.swaps.fetchingQuotes; export const getQuotesFetchStartTime = (state) => state.swaps.quotesFetchStartTime; export const getSwapsCustomizationModalPrice = (state) => state.swaps.customGas.price; export const getSwapsCustomizationModalLimit = (state) => state.swaps.customGas.limit; export const swapGasPriceEstimateIsLoading = (state) => state.swaps.customGas.loading === GAS_PRICES_LOADING_STATES.LOADING; export const swapGasEstimateLoadingHasFailed = (state) => state.swaps.customGas.loading === GAS_PRICES_LOADING_STATES.INITIAL; export const getSwapGasPriceEstimateData = (state) => state.swaps.customGas.priceEstimates; export const getSwapsFallbackGasPrice = (state) => state.swaps.customGas.fallBackPrice; export function shouldShowCustomPriceTooLowWarning(state) { const { average } = getSwapGasPriceEstimateData(state); const customGasPrice = getSwapsCustomizationModalPrice(state); if (!customGasPrice || average === undefined) { return false; } const customPriceRisksSwapFailure = conversionLessThan( { value: customGasPrice, fromNumericBase: 'hex', fromDenomination: 'WEI', toDenomination: 'GWEI', }, { value: average, fromNumericBase: 'dec' }, ); return customPriceRisksSwapFailure; } // Background selectors const getSwapsState = (state) => state.metamask.swapsState; export const getSwapsFeatureLiveness = (state) => state.metamask.swapsState.swapsFeatureIsLive; export const getSwapsQuoteRefreshTime = (state) => state.metamask.swapsState.swapsQuoteRefreshTime; export const getBackgroundSwapRouteState = (state) => state.metamask.swapsState.routeState; export const getCustomSwapsGas = (state) => state.metamask.swapsState.customMaxGas; export const getCustomSwapsGasPrice = (state) => state.metamask.swapsState.customGasPrice; export const getFetchParams = (state) => state.metamask.swapsState.fetchParams; export const getQuotes = (state) => state.metamask.swapsState.quotes; export const getQuotesLastFetched = (state) => state.metamask.swapsState.quotesLastFetched; export const getSelectedQuote = (state) => { const { selectedAggId, quotes } = getSwapsState(state); return quotes[selectedAggId]; }; export const getSwapsErrorKey = (state) => getSwapsState(state)?.errorKey; export const getShowQuoteLoadingScreen = (state) => state.swaps.showQuoteLoadingScreen; export const getSwapsTokens = (state) => state.metamask.swapsState.tokens; export const getSwapsWelcomeMessageSeenStatus = (state) => state.metamask.swapsWelcomeMessageHasBeenShown; export const getTopQuote = (state) => { const { topAggId, quotes } = getSwapsState(state); return quotes[topAggId]; }; export const getApproveTxId = (state) => state.metamask.swapsState.approveTxId; export const getTradeTxId = (state) => state.metamask.swapsState.tradeTxId; export const getUsedQuote = (state) => getSelectedQuote(state) || getTopQuote(state); // Compound selectors export const getDestinationTokenInfo = (state) => getFetchParams(state)?.metaData?.destinationTokenInfo; export const getUsedSwapsGasPrice = (state) => getCustomSwapsGasPrice(state) || getSwapsFallbackGasPrice(state); export const getApproveTxParams = (state) => { const { approvalNeeded } = getSelectedQuote(state) || getTopQuote(state) || {}; if (!approvalNeeded) { return null; } const data = getSwapsState(state)?.customApproveTxData || approvalNeeded.data; const gasPrice = getUsedSwapsGasPrice(state); return { ...approvalNeeded, gasPrice, data }; }; // Actions / action-creators const { clearSwapsState, navigatedBackToBuildQuote, retriedGetQuotes, swapGasPriceEstimatesFetchCompleted, swapGasPriceEstimatesFetchStarted, swapGasPriceEstimatesFetchFailed, setAggregatorMetadata, setBalanceError, setFetchingQuotes, setFromToken, setQuotesFetchStartTime, setTopAssets, setToToken, swapCustomGasModalPriceEdited, swapCustomGasModalLimitEdited, retrievedFallbackSwapsGasPrice, swapCustomGasModalClosed, } = actions; export { clearSwapsState, setAggregatorMetadata, setBalanceError, setFetchingQuotes, setFromToken as setSwapsFromToken, setQuotesFetchStartTime as setSwapQuotesFetchStartTime, setTopAssets, setToToken as setSwapToToken, swapCustomGasModalPriceEdited, swapCustomGasModalLimitEdited, swapCustomGasModalClosed, }; export const navigateBackToBuildQuote = (history) => { return async (dispatch) => { // TODO: Ensure any fetch in progress is cancelled await dispatch(setBackgroundSwapRouteState('')); dispatch(navigatedBackToBuildQuote()); history.push(BUILD_QUOTE_ROUTE); }; }; export const prepareForRetryGetQuotes = () => { return async (dispatch) => { // TODO: Ensure any fetch in progress is cancelled await dispatch(resetSwapsPostFetchState()); dispatch(retriedGetQuotes()); }; }; export const prepareToLeaveSwaps = () => { return async (dispatch) => { dispatch(clearSwapsState()); await dispatch(resetBackgroundSwapsState()); }; }; export const swapsQuoteSelected = (aggId) => { return (dispatch) => { dispatch(swapCustomGasModalLimitEdited(null)); dispatch(setSelectedQuoteAggId(aggId)); dispatch(setSwapsTxGasLimit('')); }; }; export const fetchAndSetSwapsGasPriceInfo = () => { return async (dispatch) => { const basicEstimates = await dispatch(fetchMetaSwapsGasPriceEstimates()); if (basicEstimates?.fast) { dispatch(setSwapsTxGasPrice(decGWEIToHexWEI(basicEstimates.fast))); } }; }; export const fetchQuotesAndSetQuoteState = ( history, inputValue, maxSlippage, metaMetricsEvent, ) => { return async (dispatch, getState) => { const state = getState(); const chainId = getCurrentChainId(state); let swapsFeatureIsLive = false; try { swapsFeatureIsLive = await fetchSwapsFeatureLiveness(chainId); } catch (error) { log.error('Failed to fetch Swaps liveness, defaulting to false.', error); } await dispatch(setSwapsLiveness(swapsFeatureIsLive)); if (!swapsFeatureIsLive) { await history.push(SWAPS_MAINTENANCE_ROUTE); return; } const fetchParams = getFetchParams(state); const selectedAccount = getSelectedAccount(state); const balanceError = getBalanceError(state); const swapsDefaultToken = getSwapsDefaultToken(state); const fetchParamsFromToken = fetchParams?.metaData?.sourceTokenInfo?.symbol === swapsDefaultToken.symbol ? swapsDefaultToken : fetchParams?.metaData?.sourceTokenInfo; const selectedFromToken = getFromToken(state) || fetchParamsFromToken || {}; const selectedToToken = getToToken(state) || fetchParams?.metaData?.destinationTokenInfo || {}; const { address: fromTokenAddress, symbol: fromTokenSymbol, decimals: fromTokenDecimals, iconUrl: fromTokenIconUrl, balance: fromTokenBalance, } = selectedFromToken; const { address: toTokenAddress, symbol: toTokenSymbol, decimals: toTokenDecimals, iconUrl: toTokenIconUrl, } = selectedToToken; await dispatch(setBackgroundSwapRouteState('loading')); history.push(LOADING_QUOTES_ROUTE); dispatch(setFetchingQuotes(true)); const contractExchangeRates = getTokenExchangeRates(state); let destinationTokenAddedForSwap = false; if ( toTokenAddress && toTokenSymbol !== swapsDefaultToken.symbol && !contractExchangeRates[toTokenAddress] ) { destinationTokenAddedForSwap = true; await dispatch( addToken( toTokenAddress, toTokenSymbol, toTokenDecimals, toTokenIconUrl, true, ), ); } if ( fromTokenAddress && fromTokenSymbol !== swapsDefaultToken.symbol && !contractExchangeRates[fromTokenAddress] && fromTokenBalance && new BigNumber(fromTokenBalance, 16).gt(0) ) { dispatch( addToken( fromTokenAddress, fromTokenSymbol, fromTokenDecimals, fromTokenIconUrl, true, ), ); } const swapsTokens = getSwapsTokens(state); const sourceTokenInfo = swapsTokens?.find(({ address }) => address === fromTokenAddress) || selectedFromToken; const destinationTokenInfo = swapsTokens?.find(({ address }) => address === toTokenAddress) || selectedToToken; dispatch(setFromToken(selectedFromToken)); metaMetricsEvent({ event: 'Quotes Requested', category: 'swaps', sensitiveProperties: { token_from: fromTokenSymbol, token_from_amount: String(inputValue), token_to: toTokenSymbol, request_type: balanceError ? 'Quote' : 'Order', slippage: maxSlippage, custom_slippage: maxSlippage !== 2, anonymizedData: true, }, }); try { const fetchStartTime = Date.now(); dispatch(setQuotesFetchStartTime(fetchStartTime)); const fetchAndSetQuotesPromise = dispatch( fetchAndSetQuotes( { slippage: maxSlippage, sourceToken: fromTokenAddress, destinationToken: toTokenAddress, value: inputValue, fromAddress: selectedAccount.address, destinationTokenAddedForSwap, balanceError, sourceDecimals: fromTokenDecimals, }, { sourceTokenInfo, destinationTokenInfo, accountBalance: selectedAccount.balance, chainId, }, ), ); const gasPriceFetchPromise = dispatch(fetchAndSetSwapsGasPriceInfo()); const [[fetchedQuotes, selectedAggId]] = await Promise.all([ fetchAndSetQuotesPromise, gasPriceFetchPromise, ]); if (Object.values(fetchedQuotes)?.length === 0) { metaMetricsEvent({ event: 'No Quotes Available', category: 'swaps', sensitiveProperties: { token_from: fromTokenSymbol, token_from_amount: String(inputValue), token_to: toTokenSymbol, request_type: balanceError ? 'Quote' : 'Order', slippage: maxSlippage, custom_slippage: maxSlippage !== 2, }, }); dispatch(setSwapsErrorKey(QUOTES_NOT_AVAILABLE_ERROR)); } else { const newSelectedQuote = fetchedQuotes[selectedAggId]; metaMetricsEvent({ event: 'Quotes Received', category: 'swaps', sensitiveProperties: { token_from: fromTokenSymbol, token_from_amount: String(inputValue), token_to: toTokenSymbol, token_to_amount: calcTokenAmount( newSelectedQuote.destinationAmount, newSelectedQuote.decimals || 18, ), request_type: balanceError ? 'Quote' : 'Order', slippage: maxSlippage, custom_slippage: maxSlippage !== 2, response_time: Date.now() - fetchStartTime, best_quote_source: newSelectedQuote.aggregator, available_quotes: Object.values(fetchedQuotes)?.length, anonymizedData: true, }, }); dispatch(setInitialGasEstimate(selectedAggId)); } } catch (e) { // A newer swap request is running, so simply bail and let the newer request respond if (e.message === SWAPS_FETCH_ORDER_CONFLICT) { log.debug(`Swap fetch order conflict detected; ignoring older request`); return; } // TODO: Check for any errors we should expect to occur in production, and report others to Sentry log.error(`Error fetching quotes: `, e); dispatch(setSwapsErrorKey(ERROR_FETCHING_QUOTES)); } dispatch(setFetchingQuotes(false)); }; }; export const signAndSendTransactions = (history, metaMetricsEvent) => { return async (dispatch, getState) => { const state = getState(); const chainId = getCurrentChainId(state); let swapsFeatureIsLive = false; try { swapsFeatureIsLive = await fetchSwapsFeatureLiveness(chainId); } catch (error) { log.error('Failed to fetch Swaps liveness, defaulting to false.', error); } await dispatch(setSwapsLiveness(swapsFeatureIsLive)); if (!swapsFeatureIsLive) { await history.push(SWAPS_MAINTENANCE_ROUTE); return; } const customSwapsGas = getCustomSwapsGas(state); const fetchParams = getFetchParams(state); const { metaData, value: swapTokenValue, slippage } = fetchParams; const { sourceTokenInfo = {}, destinationTokenInfo = {} } = metaData; await dispatch(setBackgroundSwapRouteState('awaiting')); await dispatch(stopPollingForQuotes()); history.push(AWAITING_SWAP_ROUTE); const { fast: fastGasEstimate } = getSwapGasPriceEstimateData(state); const usedQuote = getUsedQuote(state); const usedTradeTxParams = usedQuote.trade; const estimatedGasLimit = new BigNumber( usedQuote?.gasEstimate || `0x0`, 16, ); const estimatedGasLimitWithMultiplier = estimatedGasLimit .times(usedQuote?.gasMultiplier || FALLBACK_GAS_MULTIPLIER, 10) .round(0) .toString(16); const maxGasLimit = customSwapsGas || (usedQuote?.gasEstimate ? estimatedGasLimitWithMultiplier : `0x${decimalToHex(usedQuote?.maxGas || 0)}`); const usedGasPrice = getUsedSwapsGasPrice(state); usedTradeTxParams.gas = maxGasLimit; usedTradeTxParams.gasPrice = usedGasPrice; const usdConversionRate = getUSDConversionRate(state); const destinationValue = calcTokenAmount( usedQuote.destinationAmount, destinationTokenInfo.decimals || 18, ).toPrecision(8); const usedGasLimitEstimate = usedQuote?.gasEstimateWithRefund || `0x${decimalToHex(usedQuote?.averageGas || 0)}`; const totalGasLimitEstimate = new BigNumber(usedGasLimitEstimate, 16) .plus(usedQuote.approvalNeeded?.gas || '0x0', 16) .toString(16); const gasEstimateTotalInUSD = getValueFromWeiHex({ value: calcGasTotal(totalGasLimitEstimate, usedGasPrice), toCurrency: 'usd', conversionRate: usdConversionRate, numberOfDecimals: 6, }); const swapMetaData = { token_from: sourceTokenInfo.symbol, token_from_amount: String(swapTokenValue), token_to: destinationTokenInfo.symbol, token_to_amount: destinationValue, slippage, custom_slippage: slippage !== 2, best_quote_source: getTopQuote(state)?.aggregator, available_quotes: getQuotes(state)?.length, other_quote_selected: usedQuote.aggregator !== getTopQuote(state)?.aggregator, other_quote_selected_source: usedQuote.aggregator === getTopQuote(state)?.aggregator ? '' : usedQuote.aggregator, gas_fees: gasEstimateTotalInUSD, estimated_gas: estimatedGasLimit.toString(10), suggested_gas_price: fastGasEstimate, used_gas_price: hexWEIToDecGWEI(usedGasPrice), average_savings: usedQuote.savings?.total, performance_savings: usedQuote.savings?.performance, fee_savings: usedQuote.savings?.fee, median_metamask_fee: usedQuote.savings?.medianMetaMaskFee, }; metaMetricsEvent({ event: 'Swap Started', category: 'swaps', sensitiveProperties: swapMetaData, }); let finalApproveTxMeta; const approveTxParams = getApproveTxParams(state); if (approveTxParams) { const approveTxMeta = await dispatch( addUnapprovedTransaction( { ...approveTxParams, amount: '0x0' }, 'metamask', ), ); await dispatch(setApproveTxId(approveTxMeta.id)); finalApproveTxMeta = await dispatch( updateTransaction( { ...approveTxMeta, type: TRANSACTION_TYPES.SWAP_APPROVAL, sourceTokenSymbol: sourceTokenInfo.symbol, }, true, ), ); try { await dispatch(updateAndApproveTx(finalApproveTxMeta, true)); } catch (e) { await dispatch(setSwapsErrorKey(SWAP_FAILED_ERROR)); history.push(SWAPS_ERROR_ROUTE); return; } } const tradeTxMeta = await dispatch( addUnapprovedTransaction(usedTradeTxParams, 'metamask'), ); dispatch(setTradeTxId(tradeTxMeta.id)); // The simulationFails property is added during the transaction controllers // addUnapprovedTransaction call if the estimateGas call fails. In cases // when no approval is required, this indicates that the swap will likely // fail. There was an earlier estimateGas call made by the swaps controller, // but it is possible that external conditions have change since then, and // a previously succeeding estimate gas call could now fail. By checking for // the `simulationFails` property here, we can reduce the number of swap // transactions that get published to the blockchain only to fail and thereby // waste the user's funds on gas. if (!approveTxParams && tradeTxMeta.simulationFails) { await dispatch(cancelTx(tradeTxMeta, false)); await dispatch(setSwapsErrorKey(SWAP_FAILED_ERROR)); history.push(SWAPS_ERROR_ROUTE); return; } const finalTradeTxMeta = await dispatch( updateTransaction( { ...tradeTxMeta, sourceTokenSymbol: sourceTokenInfo.symbol, destinationTokenSymbol: destinationTokenInfo.symbol, type: TRANSACTION_TYPES.SWAP, destinationTokenDecimals: destinationTokenInfo.decimals, destinationTokenAddress: destinationTokenInfo.address, swapMetaData, swapTokenValue, approvalTxId: finalApproveTxMeta?.id, }, true, ), ); try { await dispatch(updateAndApproveTx(finalTradeTxMeta, true)); } catch (e) { await dispatch(setSwapsErrorKey(SWAP_FAILED_ERROR)); history.push(SWAPS_ERROR_ROUTE); return; } await forceUpdateMetamaskState(dispatch); }; }; export function fetchMetaSwapsGasPriceEstimates() { return async (dispatch, getState) => { const state = getState(); const chainId = getCurrentChainId(state); dispatch(swapGasPriceEstimatesFetchStarted()); let priceEstimates; try { priceEstimates = await fetchSwapsGasPrices(chainId); } catch (e) { log.warn('Fetching swaps gas prices failed:', e); if (!e.message?.match(/NetworkError|Fetch failed with status:/u)) { throw e; } dispatch(swapGasPriceEstimatesFetchFailed()); try { const gasPrice = await global.ethQuery.gasPrice(); const gasPriceInDecGWEI = hexWEIToDecGWEI(gasPrice.toString(10)); dispatch(retrievedFallbackSwapsGasPrice(gasPriceInDecGWEI)); return null; } catch (networkGasPriceError) { console.error( `Failed to retrieve fallback gas price: `, networkGasPriceError, ); return null; } } dispatch( swapGasPriceEstimatesFetchCompleted({ priceEstimates, }), ); return priceEstimates; }; }