multi: return txns first and last indices

In this commit we introduce first and last indices for the
tranasctions returned which can be used to seek for further
transactions in a pagination style.

Signed-off-by: Abdullahi Yunus <abdoollahikbk@gmail.com>

cmd/commands/commands.go

@@ -2074,6 +2074,20 @@ var listChainTxnsCommand = cli.Command{
 				"transactions until the chain tip, including " +
 				"unconfirmed, set this value to -1",
 		},
+		cli.UintFlag{
+			Name: "index_offset",
+			Usage: "the index of a transaction that will be " +
+				"used in a query to determine which " +
+				"transaction should be returned in the " +
+				"response",
+		},
+		cli.IntFlag{
+			Name: "max_transactions",
+			Usage: "(optional) the max number of transactions to " +
+				"return; leave at default of 0 to return " +
+				"all transactions",
+			Value: 0,
+		},
 	},
 	Description: `
 	List all transactions an address of the wallet was involved in.
@@ -2096,7 +2110,10 @@ func listChainTxns(ctx *cli.Context) error {
 	client, cleanUp := getClient(ctx)
 	defer cleanUp()
 
-	req := &lnrpc.GetTransactionsRequest{}
+	req := &lnrpc.GetTransactionsRequest{
+		IndexOffset:     uint32(ctx.Uint64("index_offset")),
+		MaxTransactions: uint32(ctx.Uint64("max_transactions")),
+	}
 
 	if ctx.IsSet("start_height") {
 		req.StartHeight = int32(ctx.Int64("start_height"))

lnrpc/lightning.proto

@@ -774,6 +774,18 @@ message GetTransactionsRequest {
 message TransactionDetails {
     // The list of transactions relevant to the wallet.
     repeated Transaction transactions = 1;
+
+    /*
+    The index of the last item in the set of returned transactions. This can be
+    used to seek further, pagination style.
+    */
+    uint64 last_index = 2;
+
+    /*
+    The index of the last item in the set of returned transactions. This can be
+    used to seek backwards, pagination style.
+    */
+    uint64 first_index = 3;
 }
 
 message FeeLimit {

lnrpc/lightning.swagger.json

@@ -7520,6 +7520,16 @@
             "$ref": "#/definitions/lnrpcTransaction"
           },
           "description": "The list of transactions relevant to the wallet."
+        },
+        "last_index": {
+          "type": "string",
+          "format": "uint64",
+          "description": "The index of the last item in the set of returned transactions. This can be\nused to seek further, pagination style."
+        },
+        "first_index": {
+          "type": "string",
+          "format": "uint64",
+          "description": "The index of the last item in the set of returned transactions. This can be\nused to seek backwards, pagination style."
         }
       }
     },

lnrpc/rpc_utils.go

@@ -117,9 +117,13 @@ func RPCTransaction(tx *lnwallet.TransactionDetail) *Transaction {
 }
 
 // RPCTransactionDetails returns a set of rpc transaction details.
-func RPCTransactionDetails(txns []*lnwallet.TransactionDetail) *TransactionDetails {
+func RPCTransactionDetails(txns []*lnwallet.TransactionDetail, firstIdx,
+	lastIdx uint64) *TransactionDetails {
+
 	txDetails := &TransactionDetails{
 		Transactions: make([]*Transaction, len(txns)),
+		FirstIndex:   firstIdx,
+		LastIndex:    lastIdx,
 	}
 
 	for i, tx := range txns {

lnrpc/walletrpc/walletkit.swagger.json

@@ -1166,6 +1166,16 @@
             "$ref": "#/definitions/lnrpcTransaction"
           },
           "description": "The list of transactions relevant to the wallet."
+        },
+        "last_index": {
+          "type": "string",
+          "format": "uint64",
+          "description": "The index of the last item in the set of returned transactions. This can be\nused to seek further, pagination style."
+        },
+        "first_index": {
+          "type": "string",
+          "format": "uint64",
+          "description": "The index of the last item in the set of returned transactions. This can be\nused to seek backwards, pagination style."
         }
       }
     },

lnrpc/walletrpc/walletkit_server.go

@@ -1376,7 +1376,7 @@ func (w *WalletKit) ListSweeps(ctx context.Context,
 	// can match our list of sweeps against the list of transactions that
 	// the wallet is still tracking. Sweeps are currently always swept to
 	// the default wallet account.
-	transactions, err := w.cfg.Wallet.ListTransactionDetails(
+	txns, firstIdx, lastIdx, err := w.cfg.Wallet.ListTransactionDetails(
 		in.StartHeight, btcwallet.UnconfirmedHeight,
 		lnwallet.DefaultAccountName, 0, 0,
 	)
@@ -1389,7 +1389,7 @@ func (w *WalletKit) ListSweeps(ctx context.Context,
 		txDetails []*lnwallet.TransactionDetail
 	)
 
-	for _, tx := range transactions {
+	for _, tx := range txns {
 		_, ok := sweepTxns[tx.Hash.String()]
 		if !ok {
 			continue
@@ -1408,7 +1408,7 @@ func (w *WalletKit) ListSweeps(ctx context.Context,
 		return &ListSweepsResponse{
 			Sweeps: &ListSweepsResponse_TransactionDetails{
 				TransactionDetails: lnrpc.RPCTransactionDetails(
-					txDetails,
+					txDetails, firstIdx, lastIdx,
 				),
 			},
 		}, nil

lntest/mock/walletcontroller.go

@@ -187,9 +187,10 @@ func (w *WalletController) ListUnspentWitness(int32, int32,
 
 // ListTransactionDetails currently returns dummy values.
 func (w *WalletController) ListTransactionDetails(int32, int32,
-	string, uint32, uint32) ([]*lnwallet.TransactionDetail, error) {
+	string, uint32, uint32) ([]*lnwallet.TransactionDetail,
+	uint64, uint64, error) {
 
-	return nil, nil
+	return nil, 0, 0, nil
 }
 
 // LeaseOutput returns the current time and a nil error.

lnwallet/btcwallet/btcwallet.go

@@ -1555,7 +1555,8 @@ func unminedTransactionsToDetail(
 // This is a part of the WalletController interface.
 func (b *BtcWallet) ListTransactionDetails(startHeight, endHeight int32,
 	accountFilter string, indexOffset uint32,
-	maxTransactons uint32) ([]*lnwallet.TransactionDetail, error) {
+	maxTransactions uint32) ([]*lnwallet.TransactionDetail, uint64, uint64,
+	error) {
 
 	// Grab the best block the wallet knows of, we'll use this to calculate
 	// # of confirmations shortly below.
@@ -1567,7 +1568,7 @@ func (b *BtcWallet) ListTransactionDetails(startHeight, endHeight int32,
 	stop := base.NewBlockIdentifierFromHeight(endHeight)
 	txns, err := b.wallet.GetTransactions(start, stop, accountFilter, nil)
 	if err != nil {
-		return nil, err
+		return nil, 0, 0, err
 	}
 
 	txDetails := make([]*lnwallet.TransactionDetail, 0,
@@ -1581,7 +1582,7 @@ func (b *BtcWallet) ListTransactionDetails(startHeight, endHeight int32,
 			currentHeight, blockPackage, b.netParams,
 		)
 		if err != nil {
-			return nil, err
+			return nil, 0, 0, err
 		}
 
 		txDetails = append(txDetails, details...)
@@ -1589,7 +1590,7 @@ func (b *BtcWallet) ListTransactionDetails(startHeight, endHeight int32,
 	for _, tx := range txns.UnminedTransactions {
 		detail, err := unminedTransactionsToDetail(tx, b.netParams)
 		if err != nil {
-			return nil, err
+			return nil, 0, 0, err
 		}
 
 		txDetails = append(txDetails, detail)
@@ -1598,19 +1599,29 @@ func (b *BtcWallet) ListTransactionDetails(startHeight, endHeight int32,
 	// Return empty transaction list, if offset is more than all
 	// transactions.
 	if int(indexOffset) >= len(txDetails) {
-		return []*lnwallet.TransactionDetail{}, nil
+		txDetails = []*lnwallet.TransactionDetail{}
+
+		return txDetails, 0, 0, nil
 	}
 
-	if maxTransactons == 0 {
-		return txDetails[indexOffset:], nil
+	end := indexOffset + maxTransactions
+
+	// If maxTransactions is set to 0, then we'll return all transactions
+	// starting from the offset.
+	if maxTransactions == 0 {
+		end = uint32(len(txDetails))
+		txDetails = txDetails[indexOffset:end]
+
+		return txDetails, uint64(indexOffset), uint64(end - 1), nil
 	}
 
-	end := indexOffset + maxTransactons
-	if int(end) > len(txDetails) {
+	if end > uint32(len(txDetails)) {
 		end = uint32(len(txDetails))
 	}
 
-	return txDetails[indexOffset:end], nil
+	txDetails = txDetails[indexOffset:end]
+
+	return txDetails, uint64(indexOffset), uint64(end - 1), nil
 }
 
 // txSubscriptionClient encapsulates the transaction notification client from

lnwallet/interface.go

@@ -403,7 +403,8 @@ type WalletController interface {
 	// empty, transactions of all wallet accounts are returned.
 	ListTransactionDetails(startHeight, endHeight int32,
 		accountFilter string, indexOffset uint32,
-		maxTransactions uint32) ([]*TransactionDetail, error)
+		maxTransactions uint32) ([]*TransactionDetail, uint64, uint64,
+		error)
 
 	// LeaseOutput locks an output to the given ID, preventing it from being
 	// available for any future coin selection attempts. The absolute time

lnwallet/mock.go

@@ -198,9 +198,9 @@ func (w *mockWalletController) ListUnspentWitness(int32, int32,
 
 // ListTransactionDetails currently returns dummy values.
 func (w *mockWalletController) ListTransactionDetails(int32, int32,
-	string, uint32, uint32) ([]*TransactionDetail, error) {
+	string, uint32, uint32) ([]*TransactionDetail, uint64, uint64, error) {
 
-	return nil, nil
+	return nil, 0, 0, nil
 }
 
 // LeaseOutput returns the current time and a nil error.

lnwallet/test/test_interface.go

@@ -199,7 +199,7 @@ func assertTxInWallet(t *testing.T, w *lnwallet.LightningWallet,
 	// We'll fetch all of our transaction and go through each one until
 	// finding the expected transaction with its expected confirmation
 	// status.
-	txs, err := w.ListTransactionDetails(
+	txs, _, _, err := w.ListTransactionDetails(
 		0, btcwallet.UnconfirmedHeight, "", 0, 1000,
 	)
 	require.NoError(t, err, "unable to retrieve transactions")
@@ -1103,7 +1103,7 @@ func testListTransactionDetails(miner *rpctest.Harness,
 	// should be confirmed.
 	err = waitForWalletSync(miner, alice)
 	require.NoError(t, err, "Couldn't sync Alice's wallet")
-	txDetails, err := alice.ListTransactionDetails(
+	txDetails, _, _, err := alice.ListTransactionDetails(
 		startHeight, chainTip, "", 0, 1000,
 	)
 	require.NoError(t, err, "unable to fetch tx details")
@@ -1215,7 +1215,7 @@ func testListTransactionDetails(miner *rpctest.Harness,
 	// unconfirmed transactions. The transaction above should be included
 	// with a confirmation height of 0, indicating that it has not been
 	// mined yet.
-	txDetails, err = alice.ListTransactionDetails(
+	txDetails, _, _, err = alice.ListTransactionDetails(
 		chainTip, btcwallet.UnconfirmedHeight, "", 0, 1000,
 	)
 	require.NoError(t, err, "unable to fetch tx details")
@@ -1268,7 +1268,7 @@ func testListTransactionDetails(miner *rpctest.Harness,
 	// transactions from the last block.
 	err = waitForWalletSync(miner, alice)
 	require.NoError(t, err, "Couldn't sync Alice's wallet")
-	txDetails, err = alice.ListTransactionDetails(
+	txDetails, _, _, err = alice.ListTransactionDetails(
 		chainTip, chainTip, "", 0, 1000,
 	)
 	require.NoError(t, err, "unable to fetch tx details")
@@ -1311,7 +1311,7 @@ func testListTransactionDetails(miner *rpctest.Harness,
 
 	// Query for transactions only in the latest block. We do not expect
 	// any transactions to be returned.
-	txDetails, err = alice.ListTransactionDetails(
+	txDetails, _, _, err = alice.ListTransactionDetails(
 		chainTip, chainTip, "", 0, 1000,
 	)
 	require.NoError(t, err, "unexpected error")

rpcserver.go

@@ -6476,15 +6476,16 @@ func (r *rpcServer) GetTransactions(ctx context.Context,
 		endHeight = req.EndHeight
 	}
 
-	transactions, err := r.server.cc.Wallet.ListTransactionDetails(
-		req.StartHeight, endHeight, req.Account, req.IndexOffset,
-		req.MaxTransactions,
-	)
+	txns, firstIdx, lastIdx, err :=
+		r.server.cc.Wallet.ListTransactionDetails(
+			req.StartHeight, endHeight, req.Account,
+			req.IndexOffset, req.MaxTransactions,
+		)
 	if err != nil {
 		return nil, err
 	}
 
-	return lnrpc.RPCTransactionDetails(transactions), nil
+	return lnrpc.RPCTransactionDetails(txns, firstIdx, lastIdx), nil
 }
 
 // DescribeGraph returns a description of the latest graph state from the PoV