Index tx.height (#2324)

Refs #2051

CHANGELOG_PENDING.md

@@ -40,3 +40,4 @@ IMPROVEMENTS:
 BUG FIXES:
 - [mempool] No longer possible to fill up linked list without getting caching
   benefits [#2180](https://github.com/tendermint/tendermint/issues/2180)
+- [state] kv store index tx.height to support search

state/txindex/kv/kv.go

@@ -89,6 +89,11 @@ func (txi *TxIndex) AddBatch(b *txindex.Batch) error {
 			}
 		}
 
+		// index tx by height
+		if txi.indexAllTags || cmn.StringInSlice(types.TxHeightKey, txi.tagsToIndex) {
+			storeBatch.Set(keyForHeight(result), hash)
+		}
+
 		// index tx by hash
 		rawBytes, err := cdc.MarshalBinaryBare(result)
 		if err != nil {
@@ -114,6 +119,11 @@ func (txi *TxIndex) Index(result *types.TxResult) error {
 		}
 	}
 
+	// index tx by height
+	if txi.indexAllTags || cmn.StringInSlice(types.TxHeightKey, txi.tagsToIndex) {
+		b.Set(keyForHeight(result), hash)
+	}
+
 	// index tx by hash
 	rawBytes, err := cdc.MarshalBinaryBare(result)
 	if err != nil {
@@ -153,12 +163,6 @@ func (txi *TxIndex) Search(q *query.Query) ([]*types.TxResult, error) {
 	// conditions to skip because they're handled before "everything else"
 	skipIndexes := make([]int, 0)
 
-	// if there is a height condition ("tx.height=3"), extract it for faster lookups
-	height, heightIndex := lookForHeight(conditions)
-	if heightIndex >= 0 {
-		skipIndexes = append(skipIndexes, heightIndex)
-	}
-
 	// extract ranges
 	// if both upper and lower bounds exist, it's better to get them in order not
 	// no iterate over kvs that are not within range.
@@ -176,6 +180,9 @@ func (txi *TxIndex) Search(q *query.Query) ([]*types.TxResult, error) {
 		}
 	}
 
+	// if there is a height condition ("tx.height=3"), extract it
+	height := lookForHeight(conditions)
+
 	// for all other conditions
 	for i, c := range conditions {
 		if cmn.IntInSlice(i, skipIndexes) {
@@ -218,13 +225,13 @@ func lookForHash(conditions []query.Condition) (hash []byte, err error, ok bool)
 	return
 }
 
-func lookForHeight(conditions []query.Condition) (height int64, index int) {
-	for i, c := range conditions {
+func lookForHeight(conditions []query.Condition) (height int64) {
+	for _, c := range conditions {
 		if c.Tag == types.TxHeightKey {
-			return c.Operand.(int64), i
+			return c.Operand.(int64)
 		}
 	}
-	return 0, -1
+	return 0
 }
 
 // special map to hold range conditions
@@ -421,6 +428,10 @@ func keyForTag(tag cmn.KVPair, result *types.TxResult) []byte {
 	return []byte(fmt.Sprintf("%s/%s/%d/%d", tag.Key, tag.Value, result.Height, result.Index))
 }
 
+func keyForHeight(result *types.TxResult) []byte {
+	return []byte(fmt.Sprintf("%s/%d/%d/%d", types.TxHeightKey, result.Height, result.Height, result.Index))
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Utils