package localnotifications import ( "encoding/json" "math/big" "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/eth-node/types" "github.com/status-im/status-go/multiaccounts/accounts" "github.com/status-im/status-go/services/wallet/transfer" "github.com/status-im/status-go/services/wallet/walletevent" ) type transactionState string const ( walletDeeplinkPrefix = "status-app://wallet/" failed transactionState = "failed" inbound transactionState = "inbound" outbound transactionState = "outbound" ) // TransactionEvent - structure used to pass messages from wallet to bus type TransactionEvent struct { Type string `json:"type"` BlockNumber *big.Int `json:"block-number"` Accounts []common.Address `json:"accounts"` MaxKnownBlocks map[common.Address]*big.Int `json:"max-known-blocks"` } type transactionBody struct { State transactionState `json:"state"` From common.Address `json:"from"` To common.Address `json:"to"` FromAccount *accounts.Account `json:"fromAccount,omitempty"` ToAccount *accounts.Account `json:"toAccount,omitempty"` Value *hexutil.Big `json:"value"` ERC20 bool `json:"erc20"` Contract common.Address `json:"contract"` Network uint64 `json:"network"` } func (t transactionBody) MarshalJSON() ([]byte, error) { type Alias transactionBody item := struct{ *Alias }{Alias: (*Alias)(&t)} return json.Marshal(item) } func (s *Service) buildTransactionNotification(rawTransfer transfer.Transfer) *Notification { log.Info("Handled a new transfer in buildTransactionNotification", "info", rawTransfer) var deeplink string var state transactionState transfer := transfer.CastToTransferView(rawTransfer) switch { case transfer.TxStatus == hexutil.Uint64(0): state = failed case transfer.Address == transfer.To: state = inbound default: state = outbound } from, err := s.accountsDB.GetAccountByAddress(types.Address(transfer.From)) if err != nil { log.Debug("Could not select From account by address", "error", err) } to, err := s.accountsDB.GetAccountByAddress(types.Address(transfer.To)) if err != nil { log.Debug("Could not select To account by address", "error", err) } if from != nil { deeplink = walletDeeplinkPrefix + from.Address.String() } else if to != nil { deeplink = walletDeeplinkPrefix + to.Address.String() } body := transactionBody{ State: state, From: transfer.From, To: transfer.Address, FromAccount: from, ToAccount: to, Value: transfer.Value, ERC20: string(transfer.Type) == "erc20", Contract: transfer.Contract, Network: transfer.NetworkID, } return &Notification{ BodyType: TypeTransaction, ID: transfer.ID, Body: body, Deeplink: deeplink, Category: CategoryTransaction, } } func (s *Service) transactionsHandler(payload TransactionEvent) { log.Info("Handled a new transaction", "info", payload) limit := 20 if payload.BlockNumber != nil { for _, address := range payload.Accounts { if payload.BlockNumber.Cmp(payload.MaxKnownBlocks[address]) >= 0 { log.Info("Handled transfer for address", "info", address) transfers, err := s.walletDB.GetTransfersByAddressAndBlock(s.chainID, address, payload.BlockNumber, int64(limit)) if err != nil { log.Error("Could not fetch transfers", "error", err) } for _, transaction := range transfers { n := s.buildTransactionNotification(transaction) pushMessage(n) } } } } } // SubscribeWallet - Subscribes to wallet signals func (s *Service) SubscribeWallet(publisher *event.Feed) error { s.walletTransmitter.publisher = publisher preference, err := s.db.GetWalletPreference() if err != nil { log.Error("Failed to get wallet preference", "error", err) s.WatchingEnabled = false } else { s.WatchingEnabled = preference.Enabled } s.StartWalletWatcher() return err } // StartWalletWatcher - Forward wallet events to notifications func (s *Service) StartWalletWatcher() { if s.walletTransmitter.quit != nil { // already running, nothing to do return } if s.walletTransmitter.publisher == nil { log.Error("wallet publisher was not initialized") return } s.walletTransmitter.quit = make(chan struct{}) events := make(chan walletevent.Event, 10) sub := s.walletTransmitter.publisher.Subscribe(events) s.walletTransmitter.wg.Add(1) maxKnownBlocks := map[common.Address]*big.Int{} go func() { defer s.walletTransmitter.wg.Done() historyReady := false for { select { case <-s.walletTransmitter.quit: sub.Unsubscribe() return case err := <-sub.Err(): // technically event.Feed cannot send an error to subscription.Err channel. // the only time we will get an event is when that channel is closed. if err != nil { log.Error("wallet signals transmitter failed with", "error", err) } return case event := <-events: if event.Type == transfer.EventNewTransfers && historyReady && event.BlockNumber != nil { newBlocks := false for _, address := range event.Accounts { if _, ok := maxKnownBlocks[address]; !ok { newBlocks = true maxKnownBlocks[address] = event.BlockNumber } else if event.BlockNumber.Cmp(maxKnownBlocks[address]) == 1 { maxKnownBlocks[address] = event.BlockNumber newBlocks = true } } if newBlocks && s.WatchingEnabled { s.transmitter.publisher.Send(TransactionEvent{ Type: string(event.Type), BlockNumber: event.BlockNumber, Accounts: event.Accounts, MaxKnownBlocks: maxKnownBlocks, }) } } else if event.Type == transfer.EventRecentHistoryReady { historyReady = true if event.BlockNumber != nil { for _, address := range event.Accounts { if _, ok := maxKnownBlocks[address]; !ok { maxKnownBlocks[address] = event.BlockNumber } } } } } } }() } // StopWalletWatcher - stops watching for new wallet events func (s *Service) StopWalletWatcher() { if s.walletTransmitter.quit != nil { close(s.walletTransmitter.quit) s.walletTransmitter.wg.Wait() s.walletTransmitter.quit = nil } } // IsWatchingWallet - check if local-notifications are subscribed to wallet updates func (s *Service) IsWatchingWallet() bool { return s.walletTransmitter.quit != nil }