package token import ( "context" "database/sql" "encoding/json" "errors" "math/big" "strconv" "strings" "sync" "time" "github.com/ethereum/go-ethereum/accounts/abi/bind" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/common/hexutil" "github.com/ethereum/go-ethereum/event" "github.com/ethereum/go-ethereum/log" "github.com/status-im/status-go/contracts" "github.com/status-im/status-go/contracts/community-tokens/assets" "github.com/status-im/status-go/contracts/ethscan" "github.com/status-im/status-go/contracts/ierc20" eth_node_types "github.com/status-im/status-go/eth-node/types" "github.com/status-im/status-go/multiaccounts/accounts" "github.com/status-im/status-go/params" "github.com/status-im/status-go/protocol/communities/token" "github.com/status-im/status-go/rpc" "github.com/status-im/status-go/rpc/chain" "github.com/status-im/status-go/rpc/network" "github.com/status-im/status-go/server" "github.com/status-im/status-go/services/accounts/accountsevent" "github.com/status-im/status-go/services/communitytokens/communitytokensdatabase" "github.com/status-im/status-go/services/utils" "github.com/status-im/status-go/services/wallet/async" "github.com/status-im/status-go/services/wallet/bigint" "github.com/status-im/status-go/services/wallet/community" "github.com/status-im/status-go/services/wallet/walletevent" ) const ( EventCommunityTokenReceived walletevent.EventType = "wallet-community-token-received" ) var requestTimeout = 20 * time.Second var nativeChainAddress = common.HexToAddress("0x") type Token struct { Address common.Address `json:"address"` Name string `json:"name"` Symbol string `json:"symbol"` // Decimals defines how divisible the token is. For example, 0 would be // indivisible, whereas 18 would allow very small amounts of the token // to be traded. Decimals uint `json:"decimals"` ChainID uint64 `json:"chainId"` // PegSymbol indicates that the token is pegged to some fiat currency, using the // ISO 4217 alphabetic code. For example, an empty string means it is not // pegged, while "USD" means it's pegged to the United States Dollar. PegSymbol string `json:"pegSymbol"` Image string `json:"image,omitempty"` CommunityData *community.Data `json:"community_data,omitempty"` Verified bool `json:"verified"` TokenListID string `json:"tokenListId"` } type ReceivedToken struct { Token Amount float64 `json:"amount"` TxHash common.Hash `json:"txHash"` IsFirst bool `json:"isFirst"` } func (t *Token) IsNative() bool { return strings.EqualFold(t.Symbol, "ETH") } type List struct { Name string `json:"name"` Tokens []*Token `json:"tokens"` Source string `json:"source"` Version string `json:"version"` } type ListWrapper struct { UpdatedAt int64 `json:"updatedAt"` Data []*List `json:"data"` } type addressTokenMap = map[common.Address]*Token type storeMap = map[uint64]addressTokenMap type ManagerInterface interface { LookupTokenIdentity(chainID uint64, address common.Address, native bool) *Token LookupToken(chainID *uint64, tokenSymbol string) (token *Token, isNative bool) } // Manager is used for accessing token store. It changes the token store based on overridden tokens type Manager struct { db *sql.DB RPCClient *rpc.Client ContractMaker *contracts.ContractMaker networkManager *network.Manager stores []store // Set on init, not changed afterwards communityTokensDB *communitytokensdatabase.Database communityManager *community.Manager mediaServer *server.MediaServer walletFeed *event.Feed accountFeed *event.Feed accountWatcher *accountsevent.Watcher accountsDB *accounts.Database tokens []*Token tokenLock sync.RWMutex } func mergeTokens(sliceLists [][]*Token) []*Token { allKeys := make(map[string]bool) res := []*Token{} for _, list := range sliceLists { for _, token := range list { key := strconv.FormatUint(token.ChainID, 10) + token.Address.String() if _, value := allKeys[key]; !value { allKeys[key] = true res = append(res, token) } } } return res } func prepareTokens(networkManager *network.Manager, stores []store) []*Token { tokens := make([]*Token, 0) networks, err := networkManager.GetAll() if err != nil { return nil } for _, store := range stores { validTokens := make([]*Token, 0) for _, token := range store.GetTokens() { token.Verified = true for _, network := range networks { if network.ChainID == token.ChainID { validTokens = append(validTokens, token) break } } } tokens = mergeTokens([][]*Token{tokens, validTokens}) } return tokens } func NewTokenManager( db *sql.DB, RPCClient *rpc.Client, communityManager *community.Manager, networkManager *network.Manager, appDB *sql.DB, mediaServer *server.MediaServer, walletFeed *event.Feed, accountFeed *event.Feed, accountsDB *accounts.Database, ) *Manager { maker, _ := contracts.NewContractMaker(RPCClient) stores := []store{newUniswapStore(), newDefaultStore()} tokens := prepareTokens(networkManager, stores) return &Manager{ db: db, RPCClient: RPCClient, ContractMaker: maker, networkManager: networkManager, communityManager: communityManager, stores: stores, communityTokensDB: communitytokensdatabase.NewCommunityTokensDatabase(appDB), tokens: tokens, mediaServer: mediaServer, walletFeed: walletFeed, accountFeed: accountFeed, accountsDB: accountsDB, } } func (tm *Manager) Start() { tm.startAccountsWatcher() } func (tm *Manager) startAccountsWatcher() { if tm.accountWatcher != nil { return } tm.accountWatcher = accountsevent.NewWatcher(tm.accountsDB, tm.accountFeed, tm.onAccountsChange) tm.accountWatcher.Start() } func (tm *Manager) Stop() { tm.stopAccountsWatcher() } func (tm *Manager) stopAccountsWatcher() { if tm.accountWatcher != nil { tm.accountWatcher.Stop() tm.accountWatcher = nil } } // overrideTokensInPlace overrides tokens in the store with the ones from the networks // BEWARE: overridden tokens will have their original address removed and replaced by the one in networks func overrideTokensInPlace(networks []params.Network, tokens []*Token) { for _, network := range networks { if len(network.TokenOverrides) == 0 { continue } for _, overrideToken := range network.TokenOverrides { for _, token := range tokens { if token.Symbol == overrideToken.Symbol { token.Address = overrideToken.Address } } } } } func (tm *Manager) getTokens() []*Token { tm.tokenLock.RLock() defer tm.tokenLock.RUnlock() return tm.tokens } func (tm *Manager) SetTokens(tokens []*Token) { tm.tokenLock.Lock() defer tm.tokenLock.Unlock() tm.tokens = tokens } func (tm *Manager) FindToken(network *params.Network, tokenSymbol string) *Token { if tokenSymbol == network.NativeCurrencySymbol { return tm.ToToken(network) } return tm.GetToken(network.ChainID, tokenSymbol) } func (tm *Manager) LookupToken(chainID *uint64, tokenSymbol string) (token *Token, isNative bool) { if chainID == nil { networks, err := tm.networkManager.Get(false) if err != nil { return nil, false } for _, network := range networks { if tokenSymbol == network.NativeCurrencySymbol { return tm.ToToken(network), true } token := tm.GetToken(network.ChainID, tokenSymbol) if token != nil { return token, false } } } else { network := tm.networkManager.Find(*chainID) if network != nil && tokenSymbol == network.NativeCurrencySymbol { return tm.ToToken(network), true } return tm.GetToken(*chainID, tokenSymbol), false } return nil, false } // GetToken returns token by chainID and tokenSymbol. Use ToToken for native token func (tm *Manager) GetToken(chainID uint64, tokenSymbol string) *Token { allTokens, err := tm.GetTokens(chainID) if err != nil { return nil } for _, token := range allTokens { if token.Symbol == tokenSymbol { return token } } return nil } func (tm *Manager) LookupTokenIdentity(chainID uint64, address common.Address, native bool) *Token { network := tm.networkManager.Find(chainID) if native { return tm.ToToken(network) } return tm.FindTokenByAddress(chainID, address) } func (tm *Manager) FindTokenByAddress(chainID uint64, address common.Address) *Token { allTokens, err := tm.GetTokens(chainID) if err != nil { return nil } for _, token := range allTokens { if token.Address == address { return token } } return nil } func (tm *Manager) FindOrCreateTokenByAddress(ctx context.Context, chainID uint64, address common.Address) *Token { // If token comes datasource, simply returns it for _, token := range tm.getTokens() { if token.ChainID != chainID { continue } if token.Address == address { return token } } // Create custom token if not known or try to link with a community customTokens, err := tm.GetCustoms(false) if err != nil { return nil } for _, token := range customTokens { if token.Address == address { tm.discoverTokenCommunityID(ctx, token, address) return token } } token, err := tm.DiscoverToken(ctx, chainID, address) if err != nil { return nil } err = tm.UpsertCustom(*token) if err != nil { return nil } tm.discoverTokenCommunityID(ctx, token, address) return token } func (tm *Manager) MarkAsPreviouslyOwnedToken(token *Token, owner common.Address) (bool, error) { log.Info("Marking token as previously owned", "token", token, "owner", owner) if token == nil { return false, errors.New("token is nil") } if (owner == common.Address{}) { return false, errors.New("owner is nil") } count := 0 err := tm.db.QueryRow(`SELECT EXISTS(SELECT 1 FROM token_balances WHERE user_address = ? AND token_address = ? AND chain_id = ?)`, owner.Hex(), token.Address.Hex(), token.ChainID).Scan(&count) if err != nil || count > 0 { return false, err } _, err = tm.db.Exec(`INSERT INTO token_balances(user_address,token_name,token_symbol,token_address,token_decimals,chain_id,token_decimals,raw_balance,balance) VALUES (?,?,?,?,?,?,?,?,?)`, owner.Hex(), token.Name, token.Symbol, token.Address.Hex(), token.Decimals, token.ChainID, 0, "0", "0") return true, err } func (tm *Manager) discoverTokenCommunityID(ctx context.Context, token *Token, address common.Address) { if token == nil || token.CommunityData != nil { // Token is invalid or is alrady discovered. Nothing to do here. return } backend, err := tm.RPCClient.EthClient(token.ChainID) if err != nil { return } caller, err := assets.NewAssetsCaller(address, backend) if err != nil { return } uri, err := caller.BaseTokenURI(&bind.CallOpts{ Context: ctx, }) if err != nil { return } update, err := tm.db.Prepare("UPDATE tokens SET community_id=? WHERE network_id=? AND address=?") if err != nil { log.Error("Cannot prepare token update query", err) return } if uri == "" { // Update token community ID to prevent further checks _, err := update.Exec("", token.ChainID, token.Address) if err != nil { log.Error("Cannot update community id", err) } return } uri = strings.TrimSuffix(uri, "/") communityIDHex, err := utils.DeserializePublicKey(uri) if err != nil { return } communityID := eth_node_types.EncodeHex(communityIDHex) token.CommunityData = &community.Data{ ID: communityID, } _, err = update.Exec(communityID, token.ChainID, token.Address) if err != nil { log.Error("Cannot update community id", err) } } func (tm *Manager) FindSNT(chainID uint64) *Token { tokens, err := tm.GetTokens(chainID) if err != nil { return nil } for _, token := range tokens { if token.Symbol == "SNT" || token.Symbol == "STT" { return token } } return nil } func (tm *Manager) getNativeTokens() ([]*Token, error) { tokens := make([]*Token, 0) networks, err := tm.networkManager.Get(false) if err != nil { return nil, err } for _, network := range networks { tokens = append(tokens, tm.ToToken(network)) } return tokens, nil } func (tm *Manager) GetAllTokens() ([]*Token, error) { allTokens, err := tm.GetCustoms(true) if err != nil { log.Error("can't fetch custom tokens", "error", err) } allTokens = append(tm.getTokens(), allTokens...) overrideTokensInPlace(tm.networkManager.GetConfiguredNetworks(), allTokens) native, err := tm.getNativeTokens() if err != nil { return nil, err } allTokens = append(allTokens, native...) return allTokens, nil } func (tm *Manager) GetTokens(chainID uint64) ([]*Token, error) { tokens, err := tm.GetAllTokens() if err != nil { return nil, err } res := make([]*Token, 0) for _, token := range tokens { if token.ChainID == chainID { res = append(res, token) } } return res, nil } func (tm *Manager) GetTokensByChainIDs(chainIDs []uint64) ([]*Token, error) { tokens, err := tm.GetAllTokens() if err != nil { return nil, err } res := make([]*Token, 0) for _, token := range tokens { for _, chainID := range chainIDs { if token.ChainID == chainID { res = append(res, token) } } } return res, nil } func (tm *Manager) GetList() *ListWrapper { data := make([]*List, 0) nativeTokens, err := tm.getNativeTokens() if err == nil { data = append(data, &List{ Name: "native", Tokens: nativeTokens, Source: "native", Version: "1.0.0", }) } customTokens, err := tm.GetCustoms(true) if err == nil && len(customTokens) > 0 { data = append(data, &List{ Name: "custom", Tokens: customTokens, Source: "custom", Version: "1.0.0", }) } updatedAt := time.Now().Unix() for _, store := range tm.stores { updatedAt = store.GetUpdatedAt() data = append(data, &List{ Name: store.GetName(), Tokens: store.GetTokens(), Source: store.GetSource(), Version: store.GetVersion(), }) } return &ListWrapper{ Data: data, UpdatedAt: updatedAt, } } func (tm *Manager) DiscoverToken(ctx context.Context, chainID uint64, address common.Address) (*Token, error) { caller, err := tm.ContractMaker.NewERC20(chainID, address) if err != nil { return nil, err } name, err := caller.Name(&bind.CallOpts{ Context: ctx, }) if err != nil { return nil, err } symbol, err := caller.Symbol(&bind.CallOpts{ Context: ctx, }) if err != nil { return nil, err } decimal, err := caller.Decimals(&bind.CallOpts{ Context: ctx, }) if err != nil { return nil, err } return &Token{ Address: address, Name: name, Symbol: symbol, Decimals: uint(decimal), ChainID: chainID, }, nil } func (tm *Manager) getTokensFromDB(query string, args ...any) ([]*Token, error) { communityTokens := []*token.CommunityToken{} if tm.communityTokensDB != nil { // Error is skipped because it's only returning optional metadata communityTokens, _ = tm.communityTokensDB.GetCommunityERC20Metadata() } rows, err := tm.db.Query(query, args...) if err != nil { return nil, err } defer rows.Close() var rst []*Token for rows.Next() { token := &Token{} var communityIDDB sql.NullString err := rows.Scan(&token.Address, &token.Name, &token.Symbol, &token.Decimals, &token.ChainID, &communityIDDB) if err != nil { return nil, err } if communityIDDB.Valid { communityID := communityIDDB.String for _, communityToken := range communityTokens { if communityToken.CommunityID != communityID || uint64(communityToken.ChainID) != token.ChainID || communityToken.Symbol != token.Symbol { continue } token.Image = tm.mediaServer.MakeCommunityTokenImagesURL(communityID, token.ChainID, token.Symbol) break } token.CommunityData = &community.Data{ ID: communityID, } } _ = tm.fillCommunityData(token) rst = append(rst, token) } return rst, nil } func (tm *Manager) GetCustoms(onlyCommunityCustoms bool) ([]*Token, error) { if onlyCommunityCustoms { return tm.getTokensFromDB("SELECT address, name, symbol, decimals, network_id, community_id FROM tokens WHERE community_id IS NOT NULL AND community_id != ''") } return tm.getTokensFromDB("SELECT address, name, symbol, decimals, network_id, community_id FROM tokens") } func (tm *Manager) ToToken(network *params.Network) *Token { return &Token{ Address: common.HexToAddress("0x"), Name: network.NativeCurrencyName, Symbol: network.NativeCurrencySymbol, Decimals: uint(network.NativeCurrencyDecimals), ChainID: network.ChainID, Verified: true, } } func (tm *Manager) UpsertCustom(token Token) error { insert, err := tm.db.Prepare("INSERT OR REPLACE INTO TOKENS (network_id, address, name, symbol, decimals) VALUES (?, ?, ?, ?, ?)") if err != nil { return err } _, err = insert.Exec(token.ChainID, token.Address, token.Name, token.Symbol, token.Decimals) return err } func (tm *Manager) DeleteCustom(chainID uint64, address common.Address) error { _, err := tm.db.Exec(`DELETE FROM TOKENS WHERE address = ? and network_id = ?`, address, chainID) return err } func (tm *Manager) GetTokenBalance(ctx context.Context, client chain.ClientInterface, account common.Address, token common.Address) (*big.Int, error) { caller, err := ierc20.NewIERC20Caller(token, client) if err != nil { return nil, err } return caller.BalanceOf(&bind.CallOpts{ Context: ctx, }, account) } func (tm *Manager) GetTokenBalanceAt(ctx context.Context, client chain.ClientInterface, account common.Address, token common.Address, blockNumber *big.Int) (*big.Int, error) { caller, err := ierc20.NewIERC20Caller(token, client) if err != nil { return nil, err } balance, err := caller.BalanceOf(&bind.CallOpts{ Context: ctx, BlockNumber: blockNumber, }, account) if err != nil { if err != bind.ErrNoCode { return nil, err } balance = big.NewInt(0) } return balance, nil } func (tm *Manager) GetChainBalance(ctx context.Context, client chain.ClientInterface, account common.Address) (*big.Int, error) { return client.BalanceAt(ctx, account, nil) } func (tm *Manager) GetBalance(ctx context.Context, client chain.ClientInterface, account common.Address, token common.Address) (*big.Int, error) { if token == nativeChainAddress { return tm.GetChainBalance(ctx, client, account) } return tm.GetTokenBalance(ctx, client, account, token) } func (tm *Manager) GetBalancesByChain(parent context.Context, clients map[uint64]chain.ClientInterface, accounts, tokens []common.Address) (map[uint64]map[common.Address]map[common.Address]*hexutil.Big, error) { return tm.GetBalancesAtByChain(parent, clients, accounts, tokens, nil) } func (tm *Manager) GetBalancesAtByChain(parent context.Context, clients map[uint64]chain.ClientInterface, accounts, tokens []common.Address, atBlocks map[uint64]*big.Int) (map[uint64]map[common.Address]map[common.Address]*hexutil.Big, error) { var ( group = async.NewAtomicGroup(parent) mu sync.Mutex response = map[uint64]map[common.Address]map[common.Address]*hexutil.Big{} ) updateBalance := func(chainID uint64, account common.Address, token common.Address, balance *big.Int) { mu.Lock() if _, ok := response[chainID]; !ok { response[chainID] = map[common.Address]map[common.Address]*hexutil.Big{} } if _, ok := response[chainID][account]; !ok { response[chainID][account] = map[common.Address]*hexutil.Big{} } if _, ok := response[chainID][account][token]; !ok { zeroHex := hexutil.Big(*big.NewInt(0)) response[chainID][account][token] = &zeroHex } sum := big.NewInt(0).Add(response[chainID][account][token].ToInt(), balance) sumHex := hexutil.Big(*sum) response[chainID][account][token] = &sumHex mu.Unlock() } for clientIdx := range clients { // Keep the reference to the client. DO NOT USE A LOOP, the client will be overridden in the coroutine client := clients[clientIdx] ethScanContract, availableAtBlock, err := tm.ContractMaker.NewEthScan(client.NetworkID()) if err != nil { log.Error("error scanning contract", "err", err) return nil, err } atBlock := atBlocks[client.NetworkID()] fetchChainBalance := false var tokenChunks [][]common.Address chunkSize := 500 for i := 0; i < len(tokens); i += chunkSize { end := i + chunkSize if end > len(tokens) { end = len(tokens) } tokenChunks = append(tokenChunks, tokens[i:end]) } for _, token := range tokens { if token == nativeChainAddress { fetchChainBalance = true } } if fetchChainBalance { group.Add(func(parent context.Context) error { ctx, cancel := context.WithTimeout(parent, requestTimeout) defer cancel() res, err := ethScanContract.EtherBalances(&bind.CallOpts{ Context: ctx, BlockNumber: atBlock, }, accounts) if err != nil { log.Error("can't fetch chain balance 5", err) return nil } for idx, account := range accounts { balance := new(big.Int) balance.SetBytes(res[idx].Data) updateBalance(client.NetworkID(), account, common.HexToAddress("0x"), balance) } return nil }) } for accountIdx := range accounts { // Keep the reference to the account. DO NOT USE A LOOP, the account will be overridden in the coroutine account := accounts[accountIdx] for idx := range tokenChunks { // Keep the reference to the chunk. DO NOT USE A LOOP, the chunk will be overridden in the coroutine chunk := tokenChunks[idx] group.Add(func(parent context.Context) error { ctx, cancel := context.WithTimeout(parent, requestTimeout) defer cancel() var res []ethscan.BalanceScannerResult if atBlock == nil || big.NewInt(int64(availableAtBlock)).Cmp(atBlock) < 0 { res, err = ethScanContract.TokensBalance(&bind.CallOpts{ Context: ctx, BlockNumber: atBlock, }, account, chunk) if err != nil { log.Error("can't fetch erc20 token balance 6", "account", account, "error", err) return nil } if len(res) != len(chunk) { log.Error("can't fetch erc20 token balance 7", "account", account, "error response not complete") return nil } for idx, token := range chunk { if !res[idx].Success { continue } balance := new(big.Int) balance.SetBytes(res[idx].Data) updateBalance(client.NetworkID(), account, token, balance) } return nil } for _, token := range chunk { balance, err := tm.GetTokenBalanceAt(ctx, client, account, token, atBlock) if err != nil { if err != bind.ErrNoCode { log.Error("can't fetch erc20 token balance 8", "account", account, "token", token, "error on fetching token balance") return nil } } updateBalance(client.NetworkID(), account, token, balance) } return nil }) } } } select { case <-group.WaitAsync(): case <-parent.Done(): return nil, parent.Err() } return response, group.Error() } func (tm *Manager) SignalCommunityTokenReceived(address common.Address, txHash common.Hash, value *big.Int, t *Token, isFirst bool) { if tm.walletFeed == nil || t == nil || t.CommunityData == nil { return } if len(t.CommunityData.Name) == 0 { _ = tm.fillCommunityData(t) } if len(t.CommunityData.Name) == 0 && tm.communityManager != nil { communityData, _ := tm.communityManager.FetchCommunityMetadata(t.CommunityData.ID) if communityData != nil { t.CommunityData.Name = communityData.CommunityName t.CommunityData.Color = communityData.CommunityColor t.CommunityData.Image = tm.communityManager.GetCommunityImageURL(t.CommunityData.ID) } } floatAmount, _ := new(big.Float).Quo(new(big.Float).SetInt(value), new(big.Float).SetInt(new(big.Int).Exp(big.NewInt(10), big.NewInt(int64(t.Decimals)), nil))).Float64() t.Image = tm.mediaServer.MakeCommunityTokenImagesURL(t.CommunityData.ID, t.ChainID, t.Symbol) receivedToken := ReceivedToken{ Token: *t, Amount: floatAmount, TxHash: txHash, IsFirst: isFirst, } encodedMessage, err := json.Marshal(receivedToken) if err != nil { return } tm.walletFeed.Send(walletevent.Event{ Type: EventCommunityTokenReceived, ChainID: t.ChainID, Accounts: []common.Address{ address, }, Message: string(encodedMessage), }) } func (tm *Manager) fillCommunityData(token *Token) error { if token == nil || token.CommunityData == nil || tm.communityManager == nil { return nil } communityInfo, _, err := tm.communityManager.GetCommunityInfo(token.CommunityData.ID) if err != nil { return err } if err == nil && communityInfo != nil { // Fetched data from cache. Cache is refreshed during every wallet token list call. token.CommunityData.Name = communityInfo.CommunityName token.CommunityData.Color = communityInfo.CommunityColor token.CommunityData.Image = communityInfo.CommunityImage } return nil } func (tm *Manager) GetTokenHistoricalBalance(account common.Address, chainID uint64, symbol string, timestamp int64) (*big.Int, error) { var balance big.Int err := tm.db.QueryRow("SELECT balance FROM balance_history WHERE currency = ? AND chain_id = ? AND address = ? AND timestamp < ? order by timestamp DESC LIMIT 1", symbol, chainID, account, timestamp).Scan((*bigint.SQLBigIntBytes)(&balance)) if err == sql.ErrNoRows { return nil, nil } else if err != nil { return nil, err } return &balance, nil } func (tm *Manager) GetPreviouslyOwnedTokens() (map[common.Address][]*Token, error) { tokenMap := make(map[common.Address][]*Token) rows, err := tm.db.Query("SELECT user_address, token_name, token_symbol, token_address, token_decimals, chain_id FROM token_balances") if err != nil { return nil, err } defer rows.Close() for rows.Next() { token := &Token{} var addressStr, tokenAddressStr string err := rows.Scan(&addressStr, &token.Name, &token.Symbol, &tokenAddressStr, &token.Decimals, &token.ChainID) if err != nil { return nil, err } address := common.HexToAddress(addressStr) if (address == common.Address{}) { continue } token.Address = common.HexToAddress(tokenAddressStr) if (token.Address == common.Address{}) { continue } if _, ok := tokenMap[address]; !ok { tokenMap[address] = make([]*Token, 0) } tokenMap[address] = append(tokenMap[address], token) } return tokenMap, nil } func (tm *Manager) removeTokenBalances(account common.Address) error { _, err := tm.db.Exec("DELETE FROM token_balances WHERE user_address = ?", account.String()) return err } func (tm *Manager) onAccountsChange(changedAddresses []common.Address, eventType accountsevent.EventType, currentAddresses []common.Address) { if eventType == accountsevent.EventTypeRemoved { for _, account := range changedAddresses { err := tm.removeTokenBalances(account) if err != nil { log.Error("token.Manager: can't remove token balances", "error", err) } } } }