cmd: more input parameters checks for listchaintxns cli command

add a parsing block height function and error when block heights would produce invalid results

cmd/commands/commands.go

@@ -2228,9 +2228,11 @@ var listChainTxnsCommand = cli.Command{
 		cli.Int64Flag{
 			Name: "end_height",
 			Usage: "the block height until which to list " +
-				"transactions, inclusive, to get " +
-				"transactions until the chain tip, including " +
-				"unconfirmed, set this value to -1",
+				"transactions, inclusive; by default this " +
+				"will return all transactions up to the " +
+				"chain tip including unconfirmed " +
+				"transactions",
+			Value: -1,
 		},
 		cli.UintFlag{
 			Name: "index_offset",
@@ -2241,7 +2243,7 @@ var listChainTxnsCommand = cli.Command{
 		},
 		cli.IntFlag{
 			Name: "max_transactions",
-			Usage: "(optional) the max number of transactions to " +
+			Usage: "the max number of transactions to " +
 				"return; leave at default of 0 to return " +
 				"all transactions",
 			Value: 0,
@@ -2251,33 +2253,51 @@ var listChainTxnsCommand = cli.Command{
 	List all transactions an address of the wallet was involved in.
 
 	This call will return a list of wallet related transactions that paid
-	to an address our wallet controls, or spent utxos that we held. The
-	start_height and end_height flags can be used to specify an inclusive
-	block range over which to query for transactions. If the end_height is
-	less than the start_height, transactions will be queried in reverse.
-	To get all transactions until the chain tip, including unconfirmed
-	transactions (identifiable with BlockHeight=0), set end_height to -1.
-	By default, this call will get all transactions our wallet was involved
-	in, including unconfirmed transactions.
-`,
+	to an address our wallet controls, or spent utxos that we held.
+
+	By default, this call will get all transactions until the chain tip, 
+	including unconfirmed transactions (end_height=-1).`,
 	Action: actionDecorator(listChainTxns),
 }
 
+func parseBlockHeightInputs(ctx *cli.Context) (int32, int32, error) {
+	startHeight := int32(ctx.Int64("start_height"))
+	endHeight := int32(ctx.Int64("end_height"))
+
+	if ctx.IsSet("start_height") && ctx.IsSet("end_height") {
+		if endHeight != -1 && startHeight > endHeight {
+			return startHeight, endHeight,
+				errors.New("start_height should " +
+					"be less than end_height if " +
+					"end_height is not equal to -1")
+		}
+	}
+
+	if startHeight < 0 {
+		return startHeight, endHeight,
+			errors.New("start_height should " +
+				"be greater than or " +
+				"equal to 0")
+	}
+
+	return startHeight, endHeight, nil
+}
+
 func listChainTxns(ctx *cli.Context) error {
 	ctxc := getContext()
 	client, cleanUp := getClient(ctx)
 	defer cleanUp()
 
+	startHeight, endHeight, err := parseBlockHeightInputs(ctx)
+	if err != nil {
+		return err
+	}
+
 	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"))
-	}
-	if ctx.IsSet("end_height") {
-		req.EndHeight = int32(ctx.Int64("end_height"))
+		StartHeight:     startHeight,
+		EndHeight:       endHeight,
 	}
 
 	resp, err := client.GetTransactions(ctxc, req)

cmd/commands/commands_test.go

@@ -2,12 +2,14 @@ package commands
 
 import (
 	"encoding/hex"
+	"flag"
 	"fmt"
 	"math"
 	"strconv"
 	"testing"
 
 	"github.com/stretchr/testify/require"
+	"github.com/urfave/cli"
 )
 
 // TestParseChanPoint tests parseChanPoint with various
@@ -328,3 +330,107 @@ func TestAppendChanID(t *testing.T) {
 		})
 	}
 }
+
+// TestParseBlockHeightInputs tests the input block heights and ensure that the
+// proper errors are returned when they could lead in invalid results.
+func TestParseBlockHeightInputs(t *testing.T) {
+	t.Parallel()
+
+	app := cli.NewApp()
+
+	startDefault, endDefault := int64(0), int64(-1)
+
+	testCases := []struct {
+		name          string
+		expectedStart int32
+		expectedEnd   int32
+		expectedErr   string
+	}{
+		{
+			name:          "start less than end",
+			expectedStart: 100,
+			expectedEnd:   200,
+			expectedErr:   "",
+		},
+		{
+			name:          "start greater than end",
+			expectedStart: 200,
+			expectedEnd:   100,
+			expectedErr: "start_height should be " +
+				"less than end_height if end_height is " +
+				"not equal to -1",
+		},
+		{
+			name:          "only start height set",
+			expectedStart: 100,
+			expectedEnd:   -1,
+			expectedErr:   "",
+		},
+		{
+			name:          "start set and end height set as -1",
+			expectedStart: 100,
+			expectedEnd:   -1,
+			expectedErr:   "",
+		},
+		{
+			name:          "neither start nor end heights defined",
+			expectedStart: 0,
+			expectedEnd:   -1,
+			expectedErr:   "",
+		},
+		{
+			name:          "only end height defined",
+			expectedStart: 0,
+			expectedEnd:   100,
+			expectedErr:   "",
+		},
+		{
+			name:          "start height is a negative",
+			expectedStart: -1,
+			expectedEnd:   100,
+			expectedErr: "start_height should be greater " +
+				"than or equal to 0",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			flagSet := flag.NewFlagSet(
+				"listchaintxns", flag.ContinueOnError,
+			)
+
+			var startHeight, endHeight int64
+			flagSet.Int64Var(
+				&startHeight, "start_height", startDefault, "",
+			)
+			flagSet.Int64Var(
+				&endHeight, "end_height", endDefault, "",
+			)
+
+			err := flagSet.Set(
+				"start_height",
+				strconv.Itoa(int(tc.expectedStart)),
+			)
+			require.NoError(
+				t, err, "failed to set start_height flag",
+			)
+
+			err = flagSet.Set(
+				"end_height", strconv.Itoa(int(tc.expectedEnd)),
+			)
+			require.NoError(
+				t, err, "failed to set end_height flag",
+			)
+
+			ctx := cli.NewContext(app, flagSet, nil)
+			start, end, err := parseBlockHeightInputs(ctx)
+			if tc.expectedErr != "" {
+				require.EqualError(t, err, tc.expectedErr)
+			} else {
+				require.NoError(t, err)
+			}
+			require.Equal(t, tc.expectedStart, start)
+			require.Equal(t, tc.expectedEnd, end)
+		})
+	}
+}