Improve bound and cache update checks (#343)

Author: 2opremio

cmd/stellar-rpc/internal/db/cursor.go

@@ -130,8 +130,8 @@ var (
 	//nolint:gochecknoglobals
 	MaxCursor = Cursor{
 		Ledger: math.MaxInt32,
-		Tx:     math.MaxInt32,
-		Op:     math.MaxInt32,
+		Tx:     toid.TransactionMask,
+		Op:     toid.OperationMask,
 		Event:  math.MaxUint32,
 	}
 )

cmd/stellar-rpc/internal/db/cursor_test.go

@@ -108,3 +108,10 @@ func TestCursorCmp(t *testing.T) {
 		}
 	}
 }
+
+func TestMaxCursor(t *testing.T) {
+	str := MaxCursor.String()
+	cursor, err := ParseCursor(str)
+	require.NoError(t, err)
+	assert.Equal(t, MaxCursor, cursor)
+}

cmd/stellar-rpc/internal/db/ledger.go

@@ -3,6 +3,7 @@ package db
 import (
 	"context"
 	"database/sql"
+	"errors"
 	"fmt"
 
 	sq "github.com/Masterminds/squirrel"
@@ -63,6 +64,9 @@ func (l ledgerReaderTx) GetLedgerRange(ctx context.Context) (ledgerbucketwindow.
 func (l ledgerReaderTx) BatchGetLedgers(ctx context.Context, sequence uint32,
 	batchSize uint,
 ) ([]xdr.LedgerCloseMeta, error) {
+	if batchSize < 1 {
+		return nil, errors.New("batch size must be greater than zero")
+	}
 	sql := sq.Select("meta").
 		From(ledgerCloseMetaTableName).
 		Where(sq.And{

cmd/stellar-rpc/internal/methods/get_events.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"math"
 	"strings"
 	"time"
 
@@ -125,6 +124,7 @@ func (g *GetEventsRequest) Valid(maxLimit uint) error {
 			return errors.New("ledger ranges and cursor cannot both be set")
 		}
 	} else if g.StartLedger <= 0 {
+		// Note: Endledger == 0 indicates it's unset (unlimited)
 		return errors.New("startLedger must be positive")
 	}
 
@@ -524,7 +524,9 @@ func (h eventsRPCHandler) getEvents(ctx context.Context, request GetEventsReques
 		// cursor represents end of the search window if events does not reach limit
 		// here endLedger is always exclusive when fetching events
 		// so search window is max Cursor value with endLedger - 1
-		cursor = db.Cursor{Ledger: endLedger - 1, Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
+		maxCursor := db.MaxCursor
+		maxCursor.Ledger = endLedger - 1
+		cursor = maxCursor.String()
 	}
 
 	return GetEventsResponse{

cmd/stellar-rpc/internal/methods/get_events_test.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"math"
 	"path"
 	"strconv"
 	"strings"
@@ -656,8 +655,10 @@ func TestGetEvents(t *testing.T) {
 				TransactionHash:          ledgerCloseMeta.TransactionHash(i).HexString(),
 			})
 		}
-		cursor := db.Cursor{Ledger: 1, Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
-		assert.Equal(t, GetEventsResponse{expected, 1, cursor}, results)
+		cursor := db.MaxCursor
+		cursor.Ledger = 1
+		cursorStr := cursor.String()
+		assert.Equal(t, GetEventsResponse{expected, 1, cursorStr}, results)
 	})
 
 	t.Run("filtering by contract id", func(t *testing.T) {
@@ -803,9 +804,11 @@ func TestGetEvents(t *testing.T) {
 				TransactionHash:          ledgerCloseMeta.TransactionHash(4).HexString(),
 			},
 		}
-		cursor := db.Cursor{Ledger: 1, Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
 
-		assert.Equal(t, GetEventsResponse{expected, 1, cursor}, results)
+		cursor := db.MaxCursor
+		cursor.Ledger = 1
+		cursorStr := cursor.String()
+		assert.Equal(t, GetEventsResponse{expected, 1, cursorStr}, results)
 
 		results, err = handler.getEvents(ctx, GetEventsRequest{
 			StartLedger: 1,
@@ -839,7 +842,7 @@ func TestGetEvents(t *testing.T) {
 
 		expected[0].ValueJSON = valueJs
 		expected[0].TopicJSON = topicsJs
-		require.Equal(t, GetEventsResponse{expected, 1, cursor}, results)
+		require.Equal(t, GetEventsResponse{expected, 1, cursorStr}, results)
 	})
 
 	t.Run("filtering by both contract id and topic", func(t *testing.T) {
@@ -950,9 +953,10 @@ func TestGetEvents(t *testing.T) {
 				TransactionHash:          ledgerCloseMeta.TransactionHash(3).HexString(),
 			},
 		}
-		cursor := db.Cursor{Ledger: 1, Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
-
-		assert.Equal(t, GetEventsResponse{expected, 1, cursor}, results)
+		cursor := db.MaxCursor
+		cursor.Ledger = 1
+		cursorStr := cursor.String()
+		assert.Equal(t, GetEventsResponse{expected, 1, cursorStr}, results)
 	})
 
 	t.Run("filtering by event type", func(t *testing.T) {
@@ -1027,9 +1031,10 @@ func TestGetEvents(t *testing.T) {
 				TransactionHash:          ledgerCloseMeta.TransactionHash(0).HexString(),
 			},
 		}
-		cursor := db.Cursor{Ledger: 1, Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
-
-		assert.Equal(t, GetEventsResponse{expected, 1, cursor}, results)
+		cursor := db.MaxCursor
+		cursor.Ledger = 1
+		cursorStr := cursor.String()
+		assert.Equal(t, GetEventsResponse{expected, 1, cursorStr}, results)
 	})
 
 	t.Run("with limit", func(t *testing.T) {
@@ -1218,7 +1223,9 @@ func TestGetEvents(t *testing.T) {
 
 		// Note: endLedger is always exclusive when fetching events
 		// so search window is always max Cursor value with endLedger - 1
-		cursor = db.Cursor{Ledger: uint32(endLedger - 1), Tx: math.MaxUint32, Event: math.MaxUint32 - 1}.String()
+		rawCursor := db.MaxCursor
+		rawCursor.Ledger = uint32(endLedger - 1)
+		cursor = rawCursor.String()
 		assert.Equal(t, GetEventsResponse{[]EventInfo{}, 5, cursor}, results)
 	})
 }