client/asset,rpcserver: Add WalletHistorian interface and RPC method

This adds a `WalletHistorian` interface which exposes a `TxHistory`
function. This will allow wallets to display the history of their
transactions. Also adds a method to the RPC server to retrieve the
wallet history.

client/asset/interface.go

@@ -33,6 +33,7 @@ const (
 	WalletTraitTokenApprover                          // The wallet is a TokenApprover
 	WalletTraitAccountLocker                          // The wallet must have enough balance for redemptions before a trade.
 	WalletTraitTicketBuyer                            // The wallet can participate in decred staking.
+	WalletTraitHistorian                              // This wallet can return its transaction history
 )
 
 // IsRescanner tests if the WalletTrait has the WalletTraitRescanner bit set.
@@ -131,6 +132,12 @@ func (wt WalletTrait) IsTicketBuyer() bool {
 	return wt&WalletTraitTicketBuyer != 0
 }
 
+// IsHistorian tests if the WalletTrait has the WalletTraitHistorian bit set,
+// which indicates the wallet implements the WalletHistorian interface.
+func (wt WalletTrait) IsHistorian() bool {
+	return wt&WalletTraitHistorian != 0
+}
+
 // DetermineWalletTraits returns the WalletTrait bitset for the provided Wallet.
 func DetermineWalletTraits(w Wallet) (t WalletTrait) {
 	if _, is := w.(Rescanner); is {
@@ -181,6 +188,9 @@ func DetermineWalletTraits(w Wallet) (t WalletTrait) {
 	if _, is := w.(TicketBuyer); is {
 		t |= WalletTraitTicketBuyer
 	}
+	if _, is := w.(TicketBuyer); is {
+		t |= WalletTraitHistorian
+	}
 	return t
 }
 
@@ -1017,6 +1027,47 @@ type TicketBuyer interface {
 	TicketPage(scanStart int32, n, skipN int) ([]*Ticket, error)
 }
 
+// TransactionType is type type of transaction made by a wallet.
+type TransactionType uint16
+
+const (
+	Send TransactionType = iota
+	Receive
+	Swap
+	Redeem
+	Refund
+	CreateBond
+	RedeemBond
+	ApproveToken
+	Acceleration
+)
+
+// WalletTransaction represents a transaction that was made by a wallet.
+type WalletTransaction struct {
+	Type           TransactionType `json:"type"`
+	ID             dex.Bytes       `json:"id"`
+	AmtIn          uint64          `json:"amtIn"`
+	AmtOut         uint64          `json:"amtOut"`
+	Fees           uint64          `json:"fees"`
+	BlockNumber    uint64          `json:"blockNumber"`
+	UpdatedBalance uint64          `json:"updatedBalance"`
+	// AdditionalData contains asset specific information, i.e. nonce
+	// for ETH.
+	AdditionalData map[string]string `json:"additionalData"`
+}
+
+// WalletHistorian is a wallet that is able to retrieve the history of all
+// transactions it has made.
+type WalletHistorian interface {
+	// TxHistory returns all the transactions a wallet has made. If refID
+	// is nil, then transactions starting from the most recent are returned
+	// (past is ignored). If past is true, the transactions prior to the
+	// refID are returned, otherwise the transactions after the refID are
+	// returned. n is the number of transactions to return. If n is <= 0,
+	// all the transactions will be returned.
+	TxHistory(n int, refID *dex.Bytes, past bool) ([]*WalletTransaction, error)
+}
+
 // Bond is the fidelity bond info generated for a certain account ID, amount,
 // and lock time. These data are intended for the "post bond" request, in which
 // the server pre-validates the unsigned transaction, the client then publishes

client/core/core.go

@@ -5769,6 +5769,21 @@ func (c *Core) MultiTrade(pw []byte, form *MultiTradeForm) ([]*Order, error) {
 	return orders, nil
 }
 
+// TxHistory returns all the transactions a wallet has made. If refID
+// is nil, then transactions starting from the most recent are returned
+// (past is ignored). If past is true, the transactions prior to the
+// refID are returned, otherwise the transactions after the refID are
+// returned. n is the number of transactions to return. If n is <= 0,
+// all the transactions will be returned
+func (c *Core) TxHistory(assetID uint32, n int, refID *dex.Bytes, past bool) ([]*asset.WalletTransaction, error) {
+	wallet, found := c.wallet(assetID)
+	if !found {
+		return nil, newError(missingWalletErr, "no wallet found for %s", unbip(assetID))
+	}
+
+	return wallet.TxHistory(n, refID, past)
+}
+
 // Trade is used to place a market or limit order.
 func (c *Core) Trade(pw []byte, form *TradeForm) (*Order, error) {
 	req, err := c.prepareTradeRequest(pw, form)

client/core/wallet.go

@@ -533,6 +533,25 @@ func (w *xcWallet) swapConfirmations(ctx context.Context, coinID []byte, contrac
 	return w.Wallet.SwapConfirmations(ctx, coinID, contract, time.UnixMilli(int64(matchTime)))
 }
 
+// TxHistory returns all the transactions a wallet has made. If refID
+// is nil, then transactions starting from the most recent are returned
+// (past is ignored). If past is true, the transactions prior to the
+// refID are returned, otherwise the transactions after the refID are
+// returned. n is the number of transactions to return. If n is <= 0,
+// all the transactions will be returned.
+func (w *xcWallet) TxHistory(n int, refID *dex.Bytes, past bool) ([]*asset.WalletTransaction, error) {
+	if !w.connected() {
+		return nil, errWalletNotConnected
+	}
+
+	historian, ok := w.Wallet.(asset.WalletHistorian)
+	if !ok {
+		return nil, fmt.Errorf("wallet does not support transaction history")
+	}
+
+	return historian.TxHistory(n, refID, past)
+}
+
 // MakeBondTx authors a DEX time-locked fidelity bond transaction if the
 // asset.Wallet implementation is a Bonder.
 func (w *xcWallet) MakeBondTx(ver uint16, amt, feeRate uint64, lockTime time.Time, priv *secp256k1.PrivateKey, acctID []byte) (*asset.Bond, func(), error) {

client/rpcserver/handlers.go

@@ -59,6 +59,7 @@ const (
 	setVSPRoute                = "setvsp"
 	purchaseTicketsRoute       = "purchasetickets"
 	setVotingPreferencesRoute  = "setvotingprefs"
+	txHistoryRoute             = "txhistory"
 )
 
 const (
@@ -130,6 +131,7 @@ var routes = map[string]func(s *RPCServer, params *RawParams) *msgjson.ResponseP
 	setVSPRoute:                handleSetVSP,
 	purchaseTicketsRoute:       handlePurchaseTickets,
 	setVotingPreferencesRoute:  handleSetVotingPreferences,
+	txHistoryRoute:             handleTxHistory,
 }
 
 // handleHelp handles requests for help. Returns general help for all commands
@@ -1033,6 +1035,22 @@ func handleSetVotingPreferences(s *RPCServer, params *RawParams) *msgjson.Respon
 	return createResponse(setVotingPreferencesRoute, "vote preferences set", nil)
 }
 
+func handleTxHistory(s *RPCServer, params *RawParams) *msgjson.ResponsePayload {
+	form, err := parseTxHistoryArgs(params)
+	if err != nil {
+		return usage(txHistoryRoute, err)
+	}
+
+	txs, err := s.core.TxHistory(form.assetID, form.num, form.refID, form.past)
+	if err != nil {
+		errMsg := fmt.Sprintf("unable to get tx history: %v", err)
+		resErr := msgjson.NewError(msgjson.RPCTxHistoryError, errMsg)
+		return createResponse(txHistoryRoute, nil, resErr)
+	}
+
+	return createResponse(txHistoryRoute, txs, nil)
+}
+
 // format concatenates thing and tail. If thing is empty, returns an empty
 // string.
 func format(thing, tail string) string {
@@ -1752,4 +1770,15 @@ an spv wallet and enables options to view and set the vsp.
 		returns: `Returns:
   string: The message "` + setVotePrefsStr + `"`,
 	},
+	txHistoryRoute: {
+		argsShort:  `assetID (n) (refTxID) (past)`,
+		cmdSummary: `Get transaction history for a wallet`,
+		argsLong: `Args:
+		  assetID (int): The asset's BIP-44 registered coin index.
+		  n (int): Optional. The number of transactions to return. If <= 0 or unset, all transactions are returned.
+		  refTxID (string): Optional. If set, the transactions before or after this tx (depending on the past argument)
+		  will be returned.
+		  past (bool): If true, the transactions before the reference tx will be returned. If false, the
+		  transactions after the reference tx will be returned.`,
+	},
 }

client/rpcserver/rpcserver.go

@@ -85,6 +85,7 @@ type clientCore interface {
 	RemoveWalletPeer(assetID uint32, host string) error
 	Notifications(int) ([]*db.Notification, error)
 	MultiTrade(pw []byte, form *core.MultiTradeForm) ([]*core.Order, error)
+	TxHistory(assetID uint32, n int, refID *dex.Bytes, past bool) ([]*asset.WalletTransaction, error)
 
 	// These are core's ticket buying interface.
 	StakeStatus(assetID uint32) (*asset.TicketStakingStatus, error)

client/rpcserver/types.go

@@ -213,6 +213,13 @@ type setVotingPreferencesForm struct {
 	voteChoices, tSpendPolicy, treasuryPolicy map[string]string
 }
 
+type txHistoryForm struct {
+	assetID uint32
+	num     int
+	refID   *dex.Bytes
+	past    bool
+}
+
 // checkNArgs checks that args and pwArgs are the correct length.
 func checkNArgs(params *RawParams, nPWArgs, nArgs []int) error {
 	// For want, one integer indicates an exact match, two are the min and max.
@@ -940,3 +947,50 @@ func parseSetVotingPreferencesArgs(params *RawParams) (*setVotingPreferencesForm
 	}
 	return form, nil
 }
+
+func parseTxHistoryArgs(params *RawParams) (*txHistoryForm, error) {
+	err := checkNArgs(params, []int{0}, []int{1, 4})
+	if err != nil {
+		return nil, err
+	}
+
+	assetID, err := checkUIntArg(params.Args[0], "assetID", 32)
+	if err != nil {
+		return nil, fmt.Errorf("invalid assetID: %v", err)
+	}
+
+	var num int64
+	if len(params.Args) > 1 {
+		num, err = checkIntArg(params.Args[1], "num", 64)
+		if err != nil {
+			return nil, fmt.Errorf("invalid num: %v", err)
+		}
+	}
+
+	var refID *dex.Bytes
+	var past bool
+	if len(params.Args) > 2 {
+		if len(params.Args) != 4 {
+			return nil, fmt.Errorf("refID provided without past")
+		}
+
+		id, err := hex.DecodeString(params.Args[2])
+		if err != nil {
+			return nil, fmt.Errorf("invalid refID: %v", err)
+		}
+		idDB := dex.Bytes(id)
+		refID = &idDB
+
+		past, err = checkBoolArg(params.Args[3], "past")
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &txHistoryForm{
+		assetID: uint32(assetID),
+		num:     int(num),
+		refID:   refID,
+		past:    past,
+	}, nil
+}

dex/msgjson/types.go

@@ -93,6 +93,7 @@ const (
 	RPCPurchaseTicketsError              // 75
 	RPCStakeStatusError                  // 76
 	RPCSetVotingPreferencesError         // 77
+	RPCTxHistoryError                    // 78
 )
 
 // Routes are destinations for a "payload" of data. The type of data being