Merge pull request #835 from tendermint/feature/indexing

Indexing DeliverTx tags

config/config.go

@@ -16,6 +16,7 @@ type Config struct {
 	P2P       *P2PConfig       `mapstructure:"p2p"`
 	Mempool   *MempoolConfig   `mapstructure:"mempool"`
 	Consensus *ConsensusConfig `mapstructure:"consensus"`
+	TxIndex   *TxIndexConfig   `mapstructure:"tx_index"`
 }
 
 // DefaultConfig returns a default configuration for a Tendermint node
@@ -26,6 +27,7 @@ func DefaultConfig() *Config {
 		P2P:        DefaultP2PConfig(),
 		Mempool:    DefaultMempoolConfig(),
 		Consensus:  DefaultConsensusConfig(),
+		TxIndex:    DefaultTxIndexConfig(),
 	}
 }
 
@@ -37,6 +39,7 @@ func TestConfig() *Config {
 		P2P:        TestP2PConfig(),
 		Mempool:    DefaultMempoolConfig(),
 		Consensus:  TestConsensusConfig(),
+		TxIndex:    DefaultTxIndexConfig(),
 	}
 }
 
@@ -93,9 +96,6 @@ type BaseConfig struct {
 	// so the app can decide if we should keep the connection or not
 	FilterPeers bool `mapstructure:"filter_peers"` // false
 
-	// What indexer to use for transactions
-	TxIndex string `mapstructure:"tx_index"`
-
 	// Database backend: leveldb | memdb
 	DBBackend string `mapstructure:"db_backend"`
 
@@ -115,7 +115,6 @@ func DefaultBaseConfig() BaseConfig {
 		ProfListenAddress: "",
 		FastSync:          true,
 		FilterPeers:       false,
-		TxIndex:           "kv",
 		DBBackend:         "leveldb",
 		DBPath:            "data",
 	}
@@ -412,6 +411,41 @@ func (c *ConsensusConfig) SetWalFile(walFile string) {
 	c.walFile = walFile
 }
 
+//-----------------------------------------------------------------------------
+// TxIndexConfig
+
+// TxIndexConfig defines the confuguration for the transaction
+// indexer, including tags to index.
+type TxIndexConfig struct {
+	// What indexer to use for transactions
+	//
+	// Options:
+	//   1) "null" (default)
+	//   2) "kv" - the simplest possible indexer, backed by key-value storage (defaults to levelDB; see DBBackend).
+	Indexer string `mapstructure:"indexer"`
+
+	// Comma-separated list of tags to index (by default the only tag is tx hash)
+	//
+	// It's recommended to index only a subset of tags due to possible memory
+	// bloat. This is, of course, depends on the indexer's DB and the volume of
+	// transactions.
+	IndexTags string `mapstructure:"index_tags"`
+
+	// When set to true, tells indexer to index all tags. Note this may be not
+	// desirable (see the comment above). IndexTags has a precedence over
+	// IndexAllTags (i.e. when given both, IndexTags will be indexed).
+	IndexAllTags bool `mapstructure:"index_all_tags"`
+}
+
+// DefaultTxIndexConfig returns a default configuration for the transaction indexer.
+func DefaultTxIndexConfig() *TxIndexConfig {
+	return &TxIndexConfig{
+		Indexer:      "kv",
+		IndexTags:    "",
+		IndexAllTags: false,
+	}
+}
+
 //-----------------------------------------------------------------------------
 // Utils
 

consensus/mempool_test.go

@@ -2,6 +2,7 @@ package consensus
 
 import (
 	"encoding/binary"
+	"fmt"
 	"testing"
 	"time"
 
@@ -188,33 +189,41 @@ func (app *CounterApplication) Info(req abci.RequestInfo) abci.ResponseInfo {
 	return abci.ResponseInfo{Data: cmn.Fmt("txs:%v", app.txCount)}
 }
 
-func (app *CounterApplication) DeliverTx(tx []byte) abci.Result {
-	return runTx(tx, &app.txCount)
+func (app *CounterApplication) DeliverTx(tx []byte) abci.ResponseDeliverTx {
+	txValue := txAsUint64(tx)
+	if txValue != uint64(app.txCount) {
+		return abci.ResponseDeliverTx{
+			Code: abci.CodeType_BadNonce,
+			Log:  fmt.Sprintf("Invalid nonce. Expected %v, got %v", app.txCount, txValue)}
+	}
+	app.txCount += 1
+	return abci.ResponseDeliverTx{Code: abci.CodeType_OK}
 }
 
-func (app *CounterApplication) CheckTx(tx []byte) abci.Result {
-	return runTx(tx, &app.mempoolTxCount)
+func (app *CounterApplication) CheckTx(tx []byte) abci.ResponseCheckTx {
+	txValue := txAsUint64(tx)
+	if txValue != uint64(app.mempoolTxCount) {
+		return abci.ResponseCheckTx{
+			Code: abci.CodeType_BadNonce,
+			Log:  fmt.Sprintf("Invalid nonce. Expected %v, got %v", app.mempoolTxCount, txValue)}
+	}
+	app.mempoolTxCount += 1
+	return abci.ResponseCheckTx{Code: abci.CodeType_OK}
 }
 
-func runTx(tx []byte, countPtr *int) abci.Result {
-	count := *countPtr
+func txAsUint64(tx []byte) uint64 {
 	tx8 := make([]byte, 8)
 	copy(tx8[len(tx8)-len(tx):], tx)
-	txValue := binary.BigEndian.Uint64(tx8)
-	if txValue != uint64(count) {
-		return abci.ErrBadNonce.AppendLog(cmn.Fmt("Invalid nonce. Expected %v, got %v", count, txValue))
-	}
-	*countPtr += 1
-	return abci.OK
+	return binary.BigEndian.Uint64(tx8)
 }
 
-func (app *CounterApplication) Commit() abci.Result {
+func (app *CounterApplication) Commit() abci.ResponseCommit {
 	app.mempoolTxCount = app.txCount
 	if app.txCount == 0 {
-		return abci.OK
+		return abci.ResponseCommit{Code: abci.CodeType_OK}
 	} else {
 		hash := make([]byte, 8)
 		binary.BigEndian.PutUint64(hash, uint64(app.txCount))
-		return abci.NewResultOK(hash, "")
+		return abci.ResponseCommit{Code: abci.CodeType_OK, Data: hash}
 	}
 }

consensus/replay.go

@@ -236,7 +236,7 @@ func (h *Handshaker) ReplayBlocks(appHash []byte, appBlockHeight int, proxyApp p
 	// If appBlockHeight == 0 it means that we are at genesis and hence should send InitChain
 	if appBlockHeight == 0 {
 		validators := types.TM2PB.Validators(h.state.Validators)
-		if err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
+		if _, err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
 			return nil, err
 		}
 	}
@@ -385,21 +385,17 @@ type mockProxyApp struct {
 	abciResponses *sm.ABCIResponses
 }
 
-func (mock *mockProxyApp) DeliverTx(tx []byte) abci.Result {
+func (mock *mockProxyApp) DeliverTx(tx []byte) abci.ResponseDeliverTx {
 	r := mock.abciResponses.DeliverTx[mock.txCount]
 	mock.txCount += 1
-	return abci.Result{
-		r.Code,
-		r.Data,
-		r.Log,
-	}
+	return *r
 }
 
-func (mock *mockProxyApp) EndBlock(height uint64) abci.ResponseEndBlock {
+func (mock *mockProxyApp) EndBlock(req abci.RequestEndBlock) abci.ResponseEndBlock {
 	mock.txCount = 0
-	return mock.abciResponses.EndBlock
+	return *mock.abciResponses.EndBlock
 }
 
-func (mock *mockProxyApp) Commit() abci.Result {
-	return abci.NewResultOK(mock.appHash, "")
+func (mock *mockProxyApp) Commit() abci.ResponseCommit {
+	return abci.ResponseCommit{Code: abci.CodeType_OK, Data: mock.appHash}
 }

consensus/replay_test.go

@@ -411,7 +411,7 @@ func buildAppStateFromChain(proxyApp proxy.AppConns,
 	}
 
 	validators := types.TM2PB.Validators(state.Validators)
-	if err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
+	if _, err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
 		panic(err)
 	}
 
@@ -447,7 +447,7 @@ func buildTMStateFromChain(config *cfg.Config, state *sm.State, chain []*types.B
 	defer proxyApp.Stop()
 
 	validators := types.TM2PB.Validators(state.Validators)
-	if err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
+	if _, err := proxyApp.Consensus().InitChainSync(abci.RequestInitChain{validators}); err != nil {
 		panic(err)
 	}
 

glide.lock

@@ -1,5 +1,5 @@
-hash: 223d8e42a118e7861cb673ea58a035e99d3a98c94e4b71fb52998d320f9c3b49
-updated: 2017-11-25T22:00:24.612202481-08:00
+hash: 8c38726da2666831affa40474117d3cef5dad083176e81fb013d7e8493b83e6f
+updated: 2017-12-01T02:14:22.08770964Z
 imports:
 - name: github.com/btcsuite/btcd
   version: 8cea3866d0f7fb12d567a20744942c0d078c7d15
@@ -98,7 +98,7 @@ imports:
   - leveldb/table
   - leveldb/util
 - name: github.com/tendermint/abci
-  version: 76ef8a0697c6179220a74c479b36c27a5b53008a
+  version: 22b491bb1952125dd2fb0730d6ca8e59e310547c
   subpackages:
   - client
   - example/counter
@@ -113,7 +113,7 @@ imports:
 - name: github.com/tendermint/go-crypto
   version: dd20358a264c772b4a83e477b0cfce4c88a7001d
 - name: github.com/tendermint/go-wire
-  version: 7d50b38b3815efe313728de77e2995c8813ce13f
+  version: 5ab49b4c6ad674da6b81442911cf713ef0afb544
   subpackages:
   - data
   - data/base58
@@ -123,7 +123,7 @@ imports:
   subpackages:
   - iavl
 - name: github.com/tendermint/tmlibs
-  version: 1e12754b3a3b5f1c23bf44c2d882faae688fb2e8
+  version: 21fb7819891997c96838308b4eba5a50b07ff03f
   subpackages:
   - autofile
   - cli
@@ -160,6 +160,8 @@ imports:
   - trace
 - name: golang.org/x/sys
   version: b98136db334ff9cb24f28a68e3be3cb6608f7630
+  subpackages:
+  - unix
 - name: golang.org/x/text
   version: 88f656faf3f37f690df1a32515b479415e1a6769
   subpackages:

glide.yaml

@@ -18,7 +18,7 @@ import:
 - package: github.com/spf13/viper
   version: v1.0.0
 - package: github.com/tendermint/abci
-  version: ~0.7.0
+  version: 22b491bb1952125dd2fb0730d6ca8e59e310547c
   subpackages:
   - client
   - example/dummy
@@ -34,7 +34,7 @@ import:
   subpackages:
   - iavl
 - package: github.com/tendermint/tmlibs
-  version: 1e12754b3a3b5f1c23bf44c2d882faae688fb2e8
+  version: develop
   subpackages:
   - autofile
   - cli

mempool/mempool_test.go

@@ -13,6 +13,7 @@ import (
 
 	"github.com/tendermint/abci/example/counter"
 	"github.com/tendermint/abci/example/dummy"
+	abci "github.com/tendermint/abci/types"
 	"github.com/tendermint/tmlibs/log"
 
 	cfg "github.com/tendermint/tendermint/config"
@@ -115,7 +116,7 @@ func TestTxsAvailable(t *testing.T) {
 
 func TestSerialReap(t *testing.T) {
 	app := counter.NewCounterApplication(true)
-	app.SetOption("serial", "on")
+	app.SetOption(abci.RequestSetOption{"serial", "on"})
 	cc := proxy.NewLocalClientCreator(app)
 
 	mempool := newMempoolWithApp(cc)
@@ -172,13 +173,19 @@ func TestSerialReap(t *testing.T) {
 		for i := start; i < end; i++ {
 			txBytes := make([]byte, 8)
 			binary.BigEndian.PutUint64(txBytes, uint64(i))
-			res := appConnCon.DeliverTxSync(txBytes)
-			if !res.IsOK() {
+			res, err := appConnCon.DeliverTxSync(txBytes)
+			if err != nil {
+				t.Errorf("Client error committing tx: %v", err)
+			}
+			if res.IsErr() {
 				t.Errorf("Error committing tx. Code:%v result:%X log:%v",
 					res.Code, res.Data, res.Log)
 			}
 		}
-		res := appConnCon.CommitSync()
+		res, err := appConnCon.CommitSync()
+		if err != nil {
+			t.Errorf("Client error committing: %v", err)
+		}
 		if len(res.Data) != 8 {
 			t.Errorf("Error committing. Hash:%X log:%v", res.Data, res.Log)
 		}

node/node.go

@@ -111,6 +111,7 @@ type Node struct {
 	proxyApp         proxy.AppConns              // connection to the application
 	rpcListeners     []net.Listener              // rpc servers
 	txIndexer        txindex.TxIndexer
+	indexerService   *txindex.IndexerService
 }
 
 // NewNode returns a new, ready to go, Tendermint Node.
@@ -173,20 +174,6 @@ func NewNode(config *cfg.Config,
 	state = sm.LoadState(stateDB)
 	state.SetLogger(stateLogger)
 
-	// Transaction indexing
-	var txIndexer txindex.TxIndexer
-	switch config.TxIndex {
-	case "kv":
-		store, err := dbProvider(&DBContext{"tx_index", config})
-		if err != nil {
-			return nil, err
-		}
-		txIndexer = kv.NewTxIndex(store)
-	default:
-		txIndexer = &null.TxIndex{}
-	}
-	state.TxIndexer = txIndexer
-
 	// Generate node PrivKey
 	privKey := crypto.GenPrivKeyEd25519()
 
@@ -293,6 +280,27 @@ func NewNode(config *cfg.Config,
 	bcReactor.SetEventBus(eventBus)
 	consensusReactor.SetEventBus(eventBus)
 
+	// Transaction indexing
+	var txIndexer txindex.TxIndexer
+	switch config.TxIndex.Indexer {
+	case "kv":
+		store, err := dbProvider(&DBContext{"tx_index", config})
+		if err != nil {
+			return nil, err
+		}
+		if config.TxIndex.IndexTags != "" {
+			txIndexer = kv.NewTxIndex(store, kv.IndexTags(strings.Split(config.TxIndex.IndexTags, ",")))
+		} else if config.TxIndex.IndexAllTags {
+			txIndexer = kv.NewTxIndex(store, kv.IndexAllTags())
+		} else {
+			txIndexer = kv.NewTxIndex(store)
+		}
+	default:
+		txIndexer = &null.TxIndex{}
+	}
+
+	indexerService := txindex.NewIndexerService(txIndexer, eventBus)
+
 	// run the profile server
 	profileHost := config.ProfListenAddress
 	if profileHost != "" {
@@ -318,6 +326,7 @@ func NewNode(config *cfg.Config,
 		consensusReactor: consensusReactor,
 		proxyApp:         proxyApp,
 		txIndexer:        txIndexer,
+		indexerService:   indexerService,
 		eventBus:         eventBus,
 	}
 	node.BaseService = *cmn.NewBaseService(logger, "Node", node)
@@ -363,6 +372,12 @@ func (n *Node) OnStart() error {
 		}
 	}
 
+	// start tx indexer
+	err = n.indexerService.Start()
+	if err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -382,6 +397,8 @@ func (n *Node) OnStop() {
 	}
 
 	n.eventBus.Stop()
+
+	n.indexerService.Stop()
 }
 
 // RunForever waits for an interrupt signal and stops the node.

proxy/app_conn.go

@@ -12,12 +12,12 @@ type AppConnConsensus interface {
 	SetResponseCallback(abcicli.Callback)
 	Error() error
 
-	InitChainSync(types.RequestInitChain) (err error)
+	InitChainSync(types.RequestInitChain) (*types.ResponseInitChain, error)
 
-	BeginBlockSync(types.RequestBeginBlock) (err error)
+	BeginBlockSync(types.RequestBeginBlock) (*types.ResponseBeginBlock, error)
 	DeliverTxAsync(tx []byte) *abcicli.ReqRes
-	EndBlockSync(height uint64) (types.ResponseEndBlock, error)
-	CommitSync() (res types.Result)
+	EndBlockSync(types.RequestEndBlock) (*types.ResponseEndBlock, error)
+	CommitSync() (*types.ResponseCommit, error)
 }
 
 type AppConnMempool interface {
@@ -33,9 +33,9 @@ type AppConnMempool interface {
 type AppConnQuery interface {
 	Error() error
 
-	EchoSync(string) (res types.Result)
-	InfoSync(types.RequestInfo) (types.ResponseInfo, error)
-	QuerySync(types.RequestQuery) (types.ResponseQuery, error)
+	EchoSync(string) (*types.ResponseEcho, error)
+	InfoSync(types.RequestInfo) (*types.ResponseInfo, error)
+	QuerySync(types.RequestQuery) (*types.ResponseQuery, error)
 
 	//	SetOptionSync(key string, value string) (res types.Result)
 }
@@ -61,11 +61,11 @@ func (app *appConnConsensus) Error() error {
 	return app.appConn.Error()
 }
 
-func (app *appConnConsensus) InitChainSync(req types.RequestInitChain) (err error) {
+func (app *appConnConsensus) InitChainSync(req types.RequestInitChain) (*types.ResponseInitChain, error) {
 	return app.appConn.InitChainSync(req)
 }
 
-func (app *appConnConsensus) BeginBlockSync(req types.RequestBeginBlock) (err error) {
+func (app *appConnConsensus) BeginBlockSync(req types.RequestBeginBlock) (*types.ResponseBeginBlock, error) {
 	return app.appConn.BeginBlockSync(req)
 }
 
@@ -73,11 +73,11 @@ func (app *appConnConsensus) DeliverTxAsync(tx []byte) *abcicli.ReqRes {
 	return app.appConn.DeliverTxAsync(tx)
 }
 
-func (app *appConnConsensus) EndBlockSync(height uint64) (types.ResponseEndBlock, error) {
-	return app.appConn.EndBlockSync(height)
+func (app *appConnConsensus) EndBlockSync(req types.RequestEndBlock) (*types.ResponseEndBlock, error) {
+	return app.appConn.EndBlockSync(req)
 }
 
-func (app *appConnConsensus) CommitSync() (res types.Result) {
+func (app *appConnConsensus) CommitSync() (*types.ResponseCommit, error) {
 	return app.appConn.CommitSync()
 }
 
@@ -131,14 +131,14 @@ func (app *appConnQuery) Error() error {
 	return app.appConn.Error()
 }
 
-func (app *appConnQuery) EchoSync(msg string) (res types.Result) {
+func (app *appConnQuery) EchoSync(msg string) (*types.ResponseEcho, error) {
 	return app.appConn.EchoSync(msg)
 }
 
-func (app *appConnQuery) InfoSync(req types.RequestInfo) (types.ResponseInfo, error) {
+func (app *appConnQuery) InfoSync(req types.RequestInfo) (*types.ResponseInfo, error) {
 	return app.appConn.InfoSync(req)
 }
 
-func (app *appConnQuery) QuerySync(reqQuery types.RequestQuery) (types.ResponseQuery, error) {
+func (app *appConnQuery) QuerySync(reqQuery types.RequestQuery) (*types.ResponseQuery, error) {
 	return app.appConn.QuerySync(reqQuery)
 }

proxy/app_conn_test.go

@@ -17,7 +17,7 @@ import (
 type AppConnTest interface {
 	EchoAsync(string) *abcicli.ReqRes
 	FlushSync() error
-	InfoSync(types.RequestInfo) (types.ResponseInfo, error)
+	InfoSync(types.RequestInfo) (*types.ResponseInfo, error)
 }
 
 type appConnTest struct {
@@ -36,7 +36,7 @@ func (app *appConnTest) FlushSync() error {
 	return app.appConn.FlushSync()
 }
 
-func (app *appConnTest) InfoSync(req types.RequestInfo) (types.ResponseInfo, error) {
+func (app *appConnTest) InfoSync(req types.RequestInfo) (*types.ResponseInfo, error) {
 	return app.appConn.InfoSync(req)
 }
 

rpc/client/event_test.go

@@ -100,7 +100,7 @@ func TestTxEventsSentWithBroadcastTxAsync(t *testing.T) {
 		require.True(ok, "%d: %#v", i, evt)
 		// make sure this is the proper tx
 		require.EqualValues(tx, txe.Tx)
-		require.True(txe.Code.IsOK())
+		require.True(txe.Result.Code.IsOK())
 	}
 }
 
@@ -132,6 +132,6 @@ func TestTxEventsSentWithBroadcastTxSync(t *testing.T) {
 		require.True(ok, "%d: %#v", i, evt)
 		// make sure this is the proper tx
 		require.EqualValues(tx, txe.Tx)
-		require.True(txe.Code.IsOK())
+		require.True(txe.Result.Code.IsOK())
 	}
 }

rpc/client/httpclient.go

@@ -163,17 +163,30 @@ func (c *HTTP) Commit(height *int) (*ctypes.ResultCommit, error) {
 
 func (c *HTTP) Tx(hash []byte, prove bool) (*ctypes.ResultTx, error) {
 	result := new(ctypes.ResultTx)
-	query := map[string]interface{}{
+	params := map[string]interface{}{
 		"hash":  hash,
 		"prove": prove,
 	}
-	_, err := c.rpc.Call("tx", query, result)
+	_, err := c.rpc.Call("tx", params, result)
 	if err != nil {
 		return nil, errors.Wrap(err, "Tx")
 	}
 	return result, nil
 }
 
+func (c *HTTP) TxSearch(query string, prove bool) ([]*ctypes.ResultTx, error) {
+	results := new([]*ctypes.ResultTx)
+	params := map[string]interface{}{
+		"query": query,
+		"prove": prove,
+	}
+	_, err := c.rpc.Call("tx_search", params, results)
+	if err != nil {
+		return nil, errors.Wrap(err, "TxSearch")
+	}
+	return *results, nil
+}
+
 func (c *HTTP) Validators(height *int) (*ctypes.ResultValidators, error) {
 	result := new(ctypes.ResultValidators)
 	_, err := c.rpc.Call("validators", map[string]interface{}{"height": height}, result)

rpc/client/interface.go

@@ -50,6 +50,7 @@ type SignClient interface {
 	Commit(height *int) (*ctypes.ResultCommit, error)
 	Validators(height *int) (*ctypes.ResultValidators, error)
 	Tx(hash []byte, prove bool) (*ctypes.ResultTx, error)
+	TxSearch(query string, prove bool) ([]*ctypes.ResultTx, error)
 }
 
 // HistoryClient shows us data from genesis to now in large chunks.

rpc/client/localclient.go

@@ -124,6 +124,10 @@ func (Local) Tx(hash []byte, prove bool) (*ctypes.ResultTx, error) {
 	return core.Tx(hash, prove)
 }
 
+func (Local) TxSearch(query string, prove bool) ([]*ctypes.ResultTx, error) {
+	return core.TxSearch(query, prove)
+}
+
 func (c *Local) Subscribe(ctx context.Context, query string, out chan<- interface{}) error {
 	q, err := tmquery.New(query)
 	if err != nil {

rpc/client/mock/abci.go

@@ -38,7 +38,7 @@ func (a ABCIApp) ABCIQueryWithOptions(path string, data data.Bytes, opts client.
 func (a ABCIApp) BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
 	res := ctypes.ResultBroadcastTxCommit{}
 	res.CheckTx = a.App.CheckTx(tx)
-	if !res.CheckTx.IsOK() {
+	if res.CheckTx.IsErr() {
 		return &res, nil
 	}
 	res.DeliverTx = a.App.DeliverTx(tx)
@@ -48,7 +48,7 @@ func (a ABCIApp) BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit
 func (a ABCIApp) BroadcastTxAsync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 	c := a.App.CheckTx(tx)
 	// and this gets written in a background thread...
-	if c.IsOK() {
+	if !c.IsErr() {
 		go func() { a.App.DeliverTx(tx) }() // nolint: errcheck
 	}
 	return &ctypes.ResultBroadcastTx{c.Code, c.Data, c.Log, tx.Hash()}, nil
@@ -57,7 +57,7 @@ func (a ABCIApp) BroadcastTxAsync(tx types.Tx) (*ctypes.ResultBroadcastTx, error
 func (a ABCIApp) BroadcastTxSync(tx types.Tx) (*ctypes.ResultBroadcastTx, error) {
 	c := a.App.CheckTx(tx)
 	// and this gets written in a background thread...
-	if c.IsOK() {
+	if !c.IsErr() {
 		go func() { a.App.DeliverTx(tx) }() // nolint: errcheck
 	}
 	return &ctypes.ResultBroadcastTx{c.Code, c.Data, c.Log, tx.Hash()}, nil

rpc/client/mock/abci_test.go

@@ -37,8 +37,8 @@ func TestABCIMock(t *testing.T) {
 		BroadcastCommit: mock.Call{
 			Args: goodTx,
 			Response: &ctypes.ResultBroadcastTxCommit{
-				CheckTx:   abci.Result{Data: data.Bytes("stand")},
-				DeliverTx: abci.Result{Data: data.Bytes("deliver")},
+				CheckTx:   abci.ResponseCheckTx{Data: data.Bytes("stand")},
+				DeliverTx: abci.ResponseDeliverTx{Data: data.Bytes("deliver")},
 			},
 			Error: errors.New("bad tx"),
 		},

rpc/client/rpc_test.go

@@ -1,6 +1,7 @@
 package client_test
 
 import (
+	"fmt"
 	"strings"
 	"testing"
 
@@ -104,7 +105,7 @@ func TestABCIQuery(t *testing.T) {
 		k, v, tx := MakeTxKV()
 		bres, err := c.BroadcastTxCommit(tx)
 		require.Nil(t, err, "%d: %+v", i, err)
-		apph := bres.Height + 1 // this is where the tx will be applied to the state
+		apph := int(bres.Height) + 1 // this is where the tx will be applied to the state
 
 		// wait before querying
 		client.WaitForHeight(c, apph, nil)
@@ -136,7 +137,7 @@ func TestAppCalls(t *testing.T) {
 		bres, err := c.BroadcastTxCommit(tx)
 		require.Nil(err, "%d: %+v", i, err)
 		require.True(bres.DeliverTx.Code.IsOK())
-		txh := bres.Height
+		txh := int(bres.Height)
 		apph := txh + 1 // this is where the tx will be applied to the state
 
 		// wait before querying
@@ -153,7 +154,7 @@ func TestAppCalls(t *testing.T) {
 		// ptx, err := c.Tx(bres.Hash, true)
 		ptx, err := c.Tx(bres.Hash, true)
 		require.Nil(err, "%d: %+v", i, err)
-		assert.Equal(txh, ptx.Height)
+		assert.EqualValues(txh, ptx.Height)
 		assert.EqualValues(tx, ptx.Tx)
 
 		// and we can even check the block is added
@@ -280,9 +281,9 @@ func TestTx(t *testing.T) {
 				require.NotNil(err)
 			} else {
 				require.Nil(err, "%+v", err)
-				assert.Equal(txHeight, ptx.Height)
+				assert.EqualValues(txHeight, ptx.Height)
 				assert.EqualValues(tx, ptx.Tx)
-				assert.Equal(0, ptx.Index)
+				assert.Zero(ptx.Index)
 				assert.True(ptx.TxResult.Code.IsOK())
 
 				// time to verify the proof
@@ -294,3 +295,50 @@ func TestTx(t *testing.T) {
 		}
 	}
 }
+
+func TestTxSearch(t *testing.T) {
+	// first we broadcast a tx
+	c := getHTTPClient()
+	_, _, tx := MakeTxKV()
+	bres, err := c.BroadcastTxCommit(tx)
+	require.Nil(t, err, "%+v", err)
+
+	txHeight := bres.Height
+	txHash := bres.Hash
+
+	anotherTxHash := types.Tx("a different tx").Hash()
+
+	for i, c := range GetClients() {
+		t.Logf("client %d", i)
+
+		// now we query for the tx.
+		// since there's only one tx, we know index=0.
+		results, err := c.TxSearch(fmt.Sprintf("tx.hash='%v'", txHash), true)
+		require.Nil(t, err, "%+v", err)
+		require.Len(t, results, 1)
+
+		ptx := results[0]
+		assert.EqualValues(t, txHeight, ptx.Height)
+		assert.EqualValues(t, tx, ptx.Tx)
+		assert.Zero(t, ptx.Index)
+		assert.True(t, ptx.TxResult.Code.IsOK())
+
+		// time to verify the proof
+		proof := ptx.Proof
+		if assert.EqualValues(t, tx, proof.Data) {
+			assert.True(t, proof.Proof.Verify(proof.Index, proof.Total, txHash, proof.RootHash))
+		}
+
+		// we query for non existing tx
+		results, err = c.TxSearch(fmt.Sprintf("tx.hash='%X'", anotherTxHash), false)
+		require.Nil(t, err, "%+v", err)
+		require.Len(t, results, 0)
+
+		// we query using a tag (see dummy application)
+		results, err = c.TxSearch("app.creator='jae'", false)
+		require.Nil(t, err, "%+v", err)
+		if len(results) == 0 {
+			t.Fatal("expected a lot of transactions")
+		}
+	}
+}

rpc/core/abci.go

@@ -93,5 +93,5 @@ func ABCIInfo() (*ctypes.ResultABCIInfo, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &ctypes.ResultABCIInfo{resInfo}, nil
+	return &ctypes.ResultABCIInfo{*resInfo}, nil
 }

rpc/core/mempool.go

@@ -154,7 +154,7 @@ func BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), subscribeTimeout)
 	defer cancel()
 	deliverTxResCh := make(chan interface{})
-	q := types.EventQueryTx(tx)
+	q := types.EventQueryTxFor(tx)
 	err := eventBus.Subscribe(ctx, "mempool", q, deliverTxResCh)
 	if err != nil {
 		err = errors.Wrap(err, "failed to subscribe to tx")
@@ -177,8 +177,8 @@ func BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
 	if checkTxR.Code != abci.CodeType_OK {
 		// CheckTx failed!
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   checkTxR.Result(),
-			DeliverTx: abci.Result{},
+			CheckTx:   *checkTxR,
+			DeliverTx: abci.ResponseDeliverTx{},
 			Hash:      tx.Hash(),
 		}, nil
 	}
@@ -191,28 +191,22 @@ func BroadcastTxCommit(tx types.Tx) (*ctypes.ResultBroadcastTxCommit, error) {
 	case deliverTxResMsg := <-deliverTxResCh:
 		deliverTxRes := deliverTxResMsg.(types.TMEventData).Unwrap().(types.EventDataTx)
 		// The tx was included in a block.
-		deliverTxR := &abci.ResponseDeliverTx{
-			Code: deliverTxRes.Code,
-			Data: deliverTxRes.Data,
-			Log:  deliverTxRes.Log,
-		}
+		deliverTxR := deliverTxRes.Result
 		logger.Info("DeliverTx passed ", "tx", data.Bytes(tx), "response", deliverTxR)
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   checkTxR.Result(),
-			DeliverTx: deliverTxR.Result(),
+			CheckTx:   *checkTxR,
+			DeliverTx: deliverTxR,
 			Hash:      tx.Hash(),
 			Height:    deliverTxRes.Height,
 		}, nil
 	case <-timer.C:
 		logger.Error("failed to include tx")
 		return &ctypes.ResultBroadcastTxCommit{
-			CheckTx:   checkTxR.Result(),
-			DeliverTx: abci.Result{},
+			CheckTx:   *checkTxR,
+			DeliverTx: abci.ResponseDeliverTx{},
 			Hash:      tx.Hash(),
 		}, fmt.Errorf("Timed out waiting for transaction to be included in a block")
 	}
-
-	panic("Should never happen!")
 }
 
 // Get unconfirmed transactions including their number.

rpc/core/routes.go

@@ -19,6 +19,7 @@ var Routes = map[string]*rpc.RPCFunc{
 	"block":                rpc.NewRPCFunc(Block, "height"),
 	"commit":               rpc.NewRPCFunc(Commit, "height"),
 	"tx":                   rpc.NewRPCFunc(Tx, "hash,prove"),
+	"tx_search":            rpc.NewRPCFunc(TxSearch, "query,prove"),
 	"validators":           rpc.NewRPCFunc(Validators, "height"),
 	"dump_consensus_state": rpc.NewRPCFunc(DumpConsensusState, ""),
 	"unconfirmed_txs":      rpc.NewRPCFunc(UnconfirmedTxs, ""),

rpc/core/tx.go

@@ -6,6 +6,7 @@ import (
 	ctypes "github.com/tendermint/tendermint/rpc/core/types"
 	"github.com/tendermint/tendermint/state/txindex/null"
 	"github.com/tendermint/tendermint/types"
+	tmquery "github.com/tendermint/tmlibs/pubsub/query"
 )
 
 // Tx allows you to query the transaction results. `nil` could mean the
@@ -82,20 +83,123 @@ func Tx(hash []byte, prove bool) (*ctypes.ResultTx, error) {
 		return nil, fmt.Errorf("Tx (%X) not found", hash)
 	}
 
-	height := int(r.Height) // XXX
-	index := int(r.Index)
+	height := r.Height
+	index := r.Index
 
 	var proof types.TxProof
 	if prove {
-		block := blockStore.LoadBlock(height)
-		proof = block.Data.Txs.Proof(index)
+		// TODO: handle overflow
+		block := blockStore.LoadBlock(int(height))
+		proof = block.Data.Txs.Proof(int(index))
 	}
 
 	return &ctypes.ResultTx{
 		Height:   height,
 		Index:    index,
-		TxResult: r.Result.Result(),
+		TxResult: r.Result,
 		Tx:       r.Tx,
 		Proof:    proof,
 	}, nil
 }
+
+// TxSearch allows you to query for multiple transactions results.
+//
+// ```shell
+// curl "localhost:46657/tx_search?query=\"account.owner='Ivan'\"&prove=true"
+// ```
+//
+// ```go
+// client := client.NewHTTP("tcp://0.0.0.0:46657", "/websocket")
+// q, err := tmquery.New("account.owner='Ivan'")
+// tx, err := client.TxSearch(q, true)
+// ```
+//
+// > The above command returns JSON structured like this:
+//
+// ```json
+// {
+//   "result": [
+//     {
+//       "proof": {
+//         "Proof": {
+//           "aunts": [
+//             "J3LHbizt806uKnABNLwG4l7gXCA=",
+//             "iblMO/M1TnNtlAefJyNCeVhjAb0=",
+//             "iVk3ryurVaEEhdeS0ohAJZ3wtB8=",
+//             "5hqMkTeGqpct51ohX0lZLIdsn7Q=",
+//             "afhsNxFnLlZgFDoyPpdQSe0bR8g="
+//           ]
+//         },
+//         "Data": "mvZHHa7HhZ4aRT0xMDA=",
+//         "RootHash": "F6541223AA46E428CB1070E9840D2C3DF3B6D776",
+//         "Total": 32,
+//         "Index": 31
+//       },
+//       "tx": "mvZHHa7HhZ4aRT0xMDA=",
+//       "tx_result": {},
+//       "index": 31,
+//       "height": 12
+//     }
+//   ],
+//   "id": "",
+//   "jsonrpc": "2.0"
+// }
+// ```
+//
+// Returns transactions matching the given query.
+//
+// ### Query Parameters
+//
+// | Parameter | Type   | Default | Required | Description                                               |
+// |-----------+--------+---------+----------+-----------------------------------------------------------|
+// | query     | string | ""      | true     | Query                                                     |
+// | prove     | bool   | false   | false    | Include proofs of the transactions inclusion in the block |
+//
+// ### Returns
+//
+// - `proof`: the `types.TxProof` object
+// - `tx`: `[]byte` - the transaction
+// - `tx_result`: the `abci.Result` object
+// - `index`: `int` - index of the transaction
+// - `height`: `int` - height of the block where this transaction was in
+func TxSearch(query string, prove bool) ([]*ctypes.ResultTx, error) {
+	// if index is disabled, return error
+	if _, ok := txIndexer.(*null.TxIndex); ok {
+		return nil, fmt.Errorf("Transaction indexing is disabled.")
+	}
+
+	q, err := tmquery.New(query)
+	if err != nil {
+		return nil, err
+	}
+
+	results, err := txIndexer.Search(q)
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO: we may want to consider putting a maximum on this length and somehow
+	// informing the user that things were truncated.
+	apiResults := make([]*ctypes.ResultTx, len(results))
+	var proof types.TxProof
+	for i, r := range results {
+		height := r.Height
+		index := r.Index
+
+		if prove {
+			// TODO: handle overflow
+			block := blockStore.LoadBlock(int(height))
+			proof = block.Data.Txs.Proof(int(index))
+		}
+
+		apiResults[i] = &ctypes.ResultTx{
+			Height:   height,
+			Index:    index,
+			TxResult: r.Result,
+			Tx:       r.Tx,
+			Proof:    proof,
+		}
+	}
+
+	return apiResults, nil
+}

rpc/core/types/responses.go

@@ -104,18 +104,18 @@ type ResultBroadcastTx struct {
 }
 
 type ResultBroadcastTxCommit struct {
-	CheckTx   abci.Result `json:"check_tx"`
-	DeliverTx abci.Result `json:"deliver_tx"`
-	Hash      data.Bytes  `json:"hash"`
-	Height    int         `json:"height"`
+	CheckTx   abci.ResponseCheckTx   `json:"check_tx"`
+	DeliverTx abci.ResponseDeliverTx `json:"deliver_tx"`
+	Hash      data.Bytes             `json:"hash"`
+	Height    uint64                 `json:"height"`
 }
 
 type ResultTx struct {
-	Height   int           `json:"height"`
-	Index    int           `json:"index"`
-	TxResult abci.Result   `json:"tx_result"`
-	Tx       types.Tx      `json:"tx"`
-	Proof    types.TxProof `json:"proof,omitempty"`
+	Height   uint64                 `json:"height"`
+	Index    uint32                 `json:"index"`
+	TxResult abci.ResponseDeliverTx `json:"tx_result"`
+	Tx       types.Tx               `json:"tx"`
+	Proof    types.TxProof          `json:"proof,omitempty"`
 }
 
 type ResultUnconfirmedTxs struct {

rpc/test/helpers.go

@@ -80,6 +80,7 @@ func GetConfig() *cfg.Config {
 		globalConfig.P2P.ListenAddress = tm
 		globalConfig.RPC.ListenAddress = rpc
 		globalConfig.RPC.GRPCListenAddress = grpc
+		globalConfig.TxIndex.IndexTags = "app.creator" // see dummy application
 	}
 	return globalConfig
 }

state/execution.go

@@ -8,7 +8,6 @@ import (
 	abci "github.com/tendermint/abci/types"
 	crypto "github.com/tendermint/go-crypto"
 	"github.com/tendermint/tendermint/proxy"
-	"github.com/tendermint/tendermint/state/txindex"
 	"github.com/tendermint/tendermint/types"
 	cmn "github.com/tendermint/tmlibs/common"
 	"github.com/tendermint/tmlibs/log"
@@ -54,36 +53,31 @@ func execBlockOnProxyApp(txEventPublisher types.TxEventPublisher, proxyAppConn p
 			// TODO: make use of this info
 			// Blocks may include invalid txs.
 			// reqDeliverTx := req.(abci.RequestDeliverTx)
-			txError := ""
 			txResult := r.DeliverTx
 			if txResult.Code == abci.CodeType_OK {
 				validTxs++
 			} else {
 				logger.Debug("Invalid tx", "code", txResult.Code, "log", txResult.Log)
 				invalidTxs++
-				txError = txResult.Code.String()
 			}
 
-			abciResponses.DeliverTx[txIndex] = txResult
-			txIndex++
-
 			// NOTE: if we count we can access the tx from the block instead of
 			// pulling it from the req
-			event := types.EventDataTx{
-				Height: block.Height,
+			txEventPublisher.PublishEventTx(types.EventDataTx{types.TxResult{
+				Height: uint64(block.Height),
+				Index:  uint32(txIndex),
 				Tx:     types.Tx(req.GetDeliverTx().Tx),
-				Data:   txResult.Data,
-				Code:   txResult.Code,
-				Log:    txResult.Log,
-				Error:  txError,
-			}
-			txEventPublisher.PublishEventTx(event)
+				Result: *txResult,
+			}})
+
+			abciResponses.DeliverTx[txIndex] = txResult
+			txIndex++
 		}
 	}
 	proxyAppConn.SetResponseCallback(proxyCb)
 
 	// Begin block
-	err := proxyAppConn.BeginBlockSync(abci.RequestBeginBlock{
+	_, err := proxyAppConn.BeginBlockSync(abci.RequestBeginBlock{
 		block.Hash(),
 		types.TM2PB.Header(block.Header),
 	})
@@ -101,7 +95,7 @@ func execBlockOnProxyApp(txEventPublisher types.TxEventPublisher, proxyAppConn p
 	}
 
 	// End block
-	abciResponses.EndBlock, err = proxyAppConn.EndBlockSync(uint64(block.Height))
+	abciResponses.EndBlock, err = proxyAppConn.EndBlockSync(abci.RequestEndBlock{uint64(block.Height)})
 	if err != nil {
 		logger.Error("Error in proxyAppConn.EndBlock", "err", err)
 		return nil, err
@@ -210,7 +204,6 @@ func (s *State) validateBlock(block *types.Block) error {
 //-----------------------------------------------------------------------------
 // ApplyBlock validates & executes the block, updates state w/ ABCI responses,
 // then commits and updates the mempool atomically, then saves state.
-// Transaction results are optionally indexed.
 
 // ApplyBlock validates the block against the state, executes it against the app,
 // commits it, and saves the block and state. It's the only function that needs to be called
@@ -225,9 +218,6 @@ func (s *State) ApplyBlock(txEventPublisher types.TxEventPublisher, proxyAppConn
 
 	fail.Fail() // XXX
 
-	// index txs. This could run in the background
-	s.indexTxs(abciResponses)
-
 	// save the results before we commit
 	s.SaveABCIResponses(abciResponses)
 
@@ -258,7 +248,11 @@ func (s *State) CommitStateUpdateMempool(proxyAppConn proxy.AppConnConsensus, bl
 	defer mempool.Unlock()
 
 	// Commit block, get hash back
-	res := proxyAppConn.CommitSync()
+	res, err := proxyAppConn.CommitSync()
+	if err != nil {
+		s.logger.Error("Client error during proxyAppConn.CommitSync", "err", err)
+		return err
+	}
 	if res.IsErr() {
 		s.logger.Error("Error in proxyAppConn.CommitSync", "err", res)
 		return res
@@ -276,26 +270,6 @@ func (s *State) CommitStateUpdateMempool(proxyAppConn proxy.AppConnConsensus, bl
 	return mempool.Update(block.Height, block.Txs)
 }
 
-func (s *State) indexTxs(abciResponses *ABCIResponses) {
-	// save the tx results using the TxIndexer
-	// NOTE: these may be overwriting, but the values should be the same.
-	batch := txindex.NewBatch(len(abciResponses.DeliverTx))
-	for i, d := range abciResponses.DeliverTx {
-		tx := abciResponses.txs[i]
-		if err := batch.Add(types.TxResult{
-			Height: uint64(abciResponses.Height),
-			Index:  uint32(i),
-			Tx:     tx,
-			Result: *d,
-		}); err != nil {
-			s.logger.Error("Error with batch.Add", "err", err)
-		}
-	}
-	if err := s.TxIndexer.AddBatch(batch); err != nil {
-		s.logger.Error("Error adding batch", "err", err)
-	}
-}
-
 // ExecCommitBlock executes and commits a block on the proxyApp without validating or mutating the state.
 // It returns the application root hash (result of abci.Commit).
 func ExecCommitBlock(appConnConsensus proxy.AppConnConsensus, block *types.Block, logger log.Logger) ([]byte, error) {
@@ -305,7 +279,11 @@ func ExecCommitBlock(appConnConsensus proxy.AppConnConsensus, block *types.Block
 		return nil, err
 	}
 	// Commit block, get hash back
-	res := appConnConsensus.CommitSync()
+	res, err := appConnConsensus.CommitSync()
+	if err != nil {
+		logger.Error("Client error during proxyAppConn.CommitSync", "err", res)
+		return nil, err
+	}
 	if res.IsErr() {
 		logger.Error("Error in proxyAppConn.CommitSync", "err", res)
 		return nil, res

state/execution_test.go

@@ -3,13 +3,11 @@ package state
 import (
 	"testing"
 
-	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	"github.com/tendermint/abci/example/dummy"
 	crypto "github.com/tendermint/go-crypto"
 	"github.com/tendermint/tendermint/proxy"
-	"github.com/tendermint/tendermint/state/txindex"
 	"github.com/tendermint/tendermint/types"
 	dbm "github.com/tendermint/tmlibs/db"
 	"github.com/tendermint/tmlibs/log"
@@ -31,8 +29,6 @@ func TestApplyBlock(t *testing.T) {
 
 	state := state()
 	state.SetLogger(log.TestingLogger())
-	indexer := &dummyIndexer{0}
-	state.TxIndexer = indexer
 
 	// make block
 	block := makeBlock(1, state)
@@ -40,7 +36,6 @@ func TestApplyBlock(t *testing.T) {
 	err = state.ApplyBlock(types.NopEventBus{}, proxyApp.Consensus(), block, block.MakePartSet(testPartSize).Header(), types.MockMempool{})
 
 	require.Nil(t, err)
-	assert.Equal(t, nTxsPerBlock, indexer.Indexed) // test indexing works
 
 	// TODO check state and mempool
 }
@@ -75,16 +70,3 @@ func makeBlock(num int, state *State) *types.Block {
 		prevBlockID, valHash, state.AppHash, testPartSize)
 	return block
 }
-
-// dummyIndexer increments counter every time we index transaction.
-type dummyIndexer struct {
-	Indexed int
-}
-
-func (indexer *dummyIndexer) Get(hash []byte) (*types.TxResult, error) {
-	return nil, nil
-}
-func (indexer *dummyIndexer) AddBatch(batch *txindex.Batch) error {
-	indexer.Indexed += batch.Size()
-	return nil
-}

state/state.go

@@ -15,8 +15,6 @@ import (
 
 	wire "github.com/tendermint/go-wire"
 
-	"github.com/tendermint/tendermint/state/txindex"
-	"github.com/tendermint/tendermint/state/txindex/null"
 	"github.com/tendermint/tendermint/types"
 )
 
@@ -61,9 +59,6 @@ type State struct {
 	// AppHash is updated after Commit
 	AppHash []byte
 
-	// TxIndexer indexes transactions
-	TxIndexer txindex.TxIndexer `json:"-"`
-
 	logger log.Logger
 }
 
@@ -95,7 +90,7 @@ func loadState(db dbm.DB, key []byte) *State {
 		return nil
 	}
 
-	s := &State{db: db, TxIndexer: &null.TxIndex{}}
+	s := &State{db: db}
 	r, n, err := bytes.NewReader(buf), new(int), new(error)
 	wire.ReadBinaryPtr(&s, r, 0, n, err)
 	if *err != nil {
@@ -114,8 +109,6 @@ func (s *State) SetLogger(l log.Logger) {
 }
 
 // Copy makes a copy of the State for mutating.
-// NOTE: Does not create a copy of TxIndexer. It creates a new pointer that points to the same
-// underlying TxIndexer.
 func (s *State) Copy() *State {
 	return &State{
 		db:                          s.db,
@@ -125,7 +118,6 @@ func (s *State) Copy() *State {
 		Validators:                  s.Validators.Copy(),
 		LastValidators:              s.LastValidators.Copy(),
 		AppHash:                     s.AppHash,
-		TxIndexer:                   s.TxIndexer,
 		LastHeightValidatorsChanged: s.LastHeightValidatorsChanged,
 		logger:  s.logger,
 		ChainID: s.ChainID,
@@ -287,7 +279,7 @@ type ABCIResponses struct {
 	Height int
 
 	DeliverTx []*abci.ResponseDeliverTx
-	EndBlock  abci.ResponseEndBlock
+	EndBlock  *abci.ResponseEndBlock
 
 	txs types.Txs // reference for indexing results by hash
 }
@@ -368,7 +360,6 @@ func MakeGenesisState(db dbm.DB, genDoc *types.GenesisDoc) (*State, error) {
 		}
 	}
 
-	// we do not need indexer during replay and in tests
 	return &State{
 		db: db,
 
@@ -381,7 +372,6 @@ func MakeGenesisState(db dbm.DB, genDoc *types.GenesisDoc) (*State, error) {
 		Validators:                  types.NewValidatorSet(validators),
 		LastValidators:              types.NewValidatorSet(nil),
 		AppHash:                     genDoc.AppHash,
-		TxIndexer:                   &null.TxIndex{},
 		LastHeightValidatorsChanged: 1,
 	}, nil
 }

state/state_test.go

@@ -78,9 +78,9 @@ func TestABCIResponsesSaveLoad(t *testing.T) {
 	// build mock responses
 	block := makeBlock(2, state)
 	abciResponses := NewABCIResponses(block)
-	abciResponses.DeliverTx[0] = &abci.ResponseDeliverTx{Data: []byte("foo")}
-	abciResponses.DeliverTx[1] = &abci.ResponseDeliverTx{Data: []byte("bar"), Log: "ok"}
-	abciResponses.EndBlock = abci.ResponseEndBlock{Diffs: []*abci.Validator{
+	abciResponses.DeliverTx[0] = &abci.ResponseDeliverTx{Data: []byte("foo"), Tags: []*abci.KVPair{}}
+	abciResponses.DeliverTx[1] = &abci.ResponseDeliverTx{Data: []byte("bar"), Log: "ok", Tags: []*abci.KVPair{}}
+	abciResponses.EndBlock = &abci.ResponseEndBlock{Diffs: []*abci.Validator{
 		{
 			PubKey: crypto.GenPrivKeyEd25519().PubKey().Bytes(),
 			Power:  10,
@@ -198,12 +198,13 @@ func makeHeaderPartsResponses(state *State, height int,
 	block := makeBlock(height, state)
 	_, val := state.Validators.GetByIndex(0)
 	abciResponses := &ABCIResponses{
-		Height: height,
+		Height:   height,
+		EndBlock: &abci.ResponseEndBlock{Diffs: []*abci.Validator{}},
 	}
 
 	// if the pubkey is new, remove the old and add the new
 	if !bytes.Equal(pubkey.Bytes(), val.PubKey.Bytes()) {
-		abciResponses.EndBlock = abci.ResponseEndBlock{
+		abciResponses.EndBlock = &abci.ResponseEndBlock{
 			Diffs: []*abci.Validator{
 				{val.PubKey.Bytes(), 0},
 				{pubkey.Bytes(), 10},

state/txindex/indexer.go

@@ -4,20 +4,24 @@ import (
 	"errors"
 
 	"github.com/tendermint/tendermint/types"
+	"github.com/tendermint/tmlibs/pubsub/query"
 )
 
 // TxIndexer interface defines methods to index and search transactions.
 type TxIndexer interface {
 
-	// AddBatch analyzes, indexes or stores a batch of transactions.
-	// NOTE: We do not specify Index method for analyzing a single transaction
-	// here because it bears heavy performance losses. Almost all advanced indexers
-	// support batching.
+	// AddBatch analyzes, indexes and stores a batch of transactions.
 	AddBatch(b *Batch) error
 
+	// Index analyzes, indexes and stores a single transaction.
+	Index(result *types.TxResult) error
+
 	// Get returns the transaction specified by hash or nil if the transaction is not indexed
 	// or stored.
 	Get(hash []byte) (*types.TxResult, error)
+
+	// Search allows you to query for transactions.
+	Search(q *query.Query) ([]*types.TxResult, error)
 }
 
 //----------------------------------------------------
@@ -26,18 +30,18 @@ type TxIndexer interface {
 // Batch groups together multiple Index operations to be performed at the same time.
 // NOTE: Batch is NOT thread-safe and must not be modified after starting its execution.
 type Batch struct {
-	Ops []types.TxResult
+	Ops []*types.TxResult
 }
 
 // NewBatch creates a new Batch.
 func NewBatch(n int) *Batch {
 	return &Batch{
-		Ops: make([]types.TxResult, n),
+		Ops: make([]*types.TxResult, n),
 	}
 }
 
 // Add or update an entry for the given result.Index.
-func (b *Batch) Add(result types.TxResult) error {
+func (b *Batch) Add(result *types.TxResult) error {
 	b.Ops[result.Index] = result
 	return nil
 }

state/txindex/indexer_service.go

@@ -0,0 +1,49 @@
+package txindex
+
+import (
+	"context"
+
+	"github.com/tendermint/tendermint/types"
+	cmn "github.com/tendermint/tmlibs/common"
+)
+
+const (
+	subscriber = "IndexerService"
+)
+
+type IndexerService struct {
+	cmn.BaseService
+
+	idr      TxIndexer
+	eventBus *types.EventBus
+}
+
+func NewIndexerService(idr TxIndexer, eventBus *types.EventBus) *IndexerService {
+	is := &IndexerService{idr: idr, eventBus: eventBus}
+	is.BaseService = *cmn.NewBaseService(nil, "IndexerService", is)
+	return is
+}
+
+// OnStart implements cmn.Service by subscribing for all transactions
+// and indexing them by tags.
+func (is *IndexerService) OnStart() error {
+	ch := make(chan interface{})
+	if err := is.eventBus.Subscribe(context.Background(), subscriber, types.EventQueryTx, ch); err != nil {
+		return err
+	}
+	go func() {
+		for event := range ch {
+			// TODO: may be not perfomant to write one event at a time
+			txResult := event.(types.TMEventData).Unwrap().(types.EventDataTx).TxResult
+			is.idr.Index(&txResult)
+		}
+	}()
+	return nil
+}
+
+// OnStop implements cmn.Service by unsubscribing from all transactions.
+func (is *IndexerService) OnStop() {
+	if is.eventBus.IsRunning() {
+		_ = is.eventBus.UnsubscribeAll(context.Background(), subscriber)
+	}
+}

state/txindex/kv/kv.go

@@ -2,25 +2,57 @@ package kv
 
 import (
 	"bytes"
+	"encoding/hex"
 	"fmt"
+	"strconv"
+	"strings"
+	"time"
 
-	"github.com/tendermint/go-wire"
-
-	db "github.com/tendermint/tmlibs/db"
+	"github.com/pkg/errors"
 
+	abci "github.com/tendermint/abci/types"
+	wire "github.com/tendermint/go-wire"
 	"github.com/tendermint/tendermint/state/txindex"
 	"github.com/tendermint/tendermint/types"
+	cmn "github.com/tendermint/tmlibs/common"
+	db "github.com/tendermint/tmlibs/db"
+	"github.com/tendermint/tmlibs/pubsub/query"
 )
 
-// TxIndex is the simplest possible indexer, backed by Key-Value storage (levelDB).
-// It can only index transaction by its identifier.
+const (
+	tagKeySeparator = "/"
+)
+
+var _ txindex.TxIndexer = (*TxIndex)(nil)
+
+// TxIndex is the simplest possible indexer, backed by key-value storage (levelDB).
 type TxIndex struct {
-	store db.DB
+	store        db.DB
+	tagsToIndex  []string
+	indexAllTags bool
+}
+
+// NewTxIndex creates new KV indexer.
+func NewTxIndex(store db.DB, options ...func(*TxIndex)) *TxIndex {
+	txi := &TxIndex{store: store, tagsToIndex: make([]string, 0), indexAllTags: false}
+	for _, o := range options {
+		o(txi)
+	}
+	return txi
+}
+
+// IndexTags is an option for setting which tags to index.
+func IndexTags(tags []string) func(*TxIndex) {
+	return func(txi *TxIndex) {
+		txi.tagsToIndex = tags
+	}
 }
 
-// NewTxIndex returns new instance of TxIndex.
-func NewTxIndex(store db.DB) *TxIndex {
-	return &TxIndex{store: store}
+// IndexAllTags is an option for indexing all tags.
+func IndexAllTags() func(*TxIndex) {
+	return func(txi *TxIndex) {
+		txi.indexAllTags = true
+	}
 }
 
 // Get gets transaction from the TxIndex storage and returns it or nil if the
@@ -46,13 +78,328 @@ func (txi *TxIndex) Get(hash []byte) (*types.TxResult, error) {
 	return txResult, nil
 }
 
-// AddBatch writes a batch of transactions into the TxIndex storage.
+// AddBatch indexes a batch of transactions using the given list of tags.
 func (txi *TxIndex) AddBatch(b *txindex.Batch) error {
 	storeBatch := txi.store.NewBatch()
+
 	for _, result := range b.Ops {
-		rawBytes := wire.BinaryBytes(&result)
-		storeBatch.Set(result.Tx.Hash(), rawBytes)
+		hash := result.Tx.Hash()
+
+		// index tx by tags
+		for _, tag := range result.Result.Tags {
+			if txi.indexAllTags || cmn.StringInSlice(tag.Key, txi.tagsToIndex) {
+				storeBatch.Set(keyForTag(tag, result), hash)
+			}
+		}
+
+		// index tx by hash
+		rawBytes := wire.BinaryBytes(result)
+		storeBatch.Set(hash, rawBytes)
 	}
+
 	storeBatch.Write()
 	return nil
 }
+
+// Index indexes a single transaction using the given list of tags.
+func (txi *TxIndex) Index(result *types.TxResult) error {
+	b := txi.store.NewBatch()
+
+	hash := result.Tx.Hash()
+
+	// index tx by tags
+	for _, tag := range result.Result.Tags {
+		if txi.indexAllTags || cmn.StringInSlice(tag.Key, txi.tagsToIndex) {
+			b.Set(keyForTag(tag, result), hash)
+		}
+	}
+
+	// index tx by hash
+	rawBytes := wire.BinaryBytes(result)
+	b.Set(hash, rawBytes)
+
+	b.Write()
+	return nil
+}
+
+// Search performs a search using the given query. It breaks the query into
+// conditions (like "tx.height > 5"). For each condition, it queries the DB
+// index. One special use cases here: (1) if "tx.hash" is found, it returns tx
+// result for it (2) for range queries it is better for the client to provide
+// both lower and upper bounds, so we are not performing a full scan. Results
+// from querying indexes are then intersected and returned to the caller.
+func (txi *TxIndex) Search(q *query.Query) ([]*types.TxResult, error) {
+	var hashes [][]byte
+	var hashesInitialized bool
+
+	// get a list of conditions (like "tx.height > 5")
+	conditions := q.Conditions()
+
+	// if there is a hash condition, return the result immediately
+	hash, err, ok := lookForHash(conditions)
+	if err != nil {
+		return nil, errors.Wrap(err, "error during searching for a hash in the query")
+	} else if ok {
+		res, err := txi.Get(hash)
+		if res == nil {
+			return []*types.TxResult{}, nil
+		} else {
+			return []*types.TxResult{res}, errors.Wrap(err, "error while retrieving the result")
+		}
+	}
+
+	// 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.
+	ranges, rangeIndexes := lookForRanges(conditions)
+	if len(ranges) > 0 {
+		skipIndexes = append(skipIndexes, rangeIndexes...)
+
+		for _, r := range ranges {
+			if !hashesInitialized {
+				hashes = txi.matchRange(r, startKeyForRange(r, height))
+				hashesInitialized = true
+			} else {
+				hashes = intersect(hashes, txi.matchRange(r, startKeyForRange(r, height)))
+			}
+		}
+	}
+
+	// for all other conditions
+	for i, c := range conditions {
+		if cmn.IntInSlice(i, skipIndexes) {
+			continue
+		}
+
+		if !hashesInitialized {
+			hashes = txi.match(c, startKey(c, height))
+			hashesInitialized = true
+		} else {
+			hashes = intersect(hashes, txi.match(c, startKey(c, height)))
+		}
+	}
+
+	results := make([]*types.TxResult, len(hashes))
+	i := 0
+	for _, h := range hashes {
+		results[i], err = txi.Get(h)
+		if err != nil {
+			return nil, errors.Wrapf(err, "failed to get Tx{%X}", h)
+		}
+		i++
+	}
+
+	return results, nil
+}
+
+func lookForHash(conditions []query.Condition) (hash []byte, err error, ok bool) {
+	for _, c := range conditions {
+		if c.Tag == types.TxHashKey {
+			decoded, err := hex.DecodeString(c.Operand.(string))
+			return decoded, err, true
+		}
+	}
+	return
+}
+
+func lookForHeight(conditions []query.Condition) (height uint64, index int) {
+	for i, c := range conditions {
+		if c.Tag == types.TxHeightKey {
+			return uint64(c.Operand.(int64)), i
+		}
+	}
+	return 0, -1
+}
+
+// special map to hold range conditions
+// Example: account.number => queryRange{lowerBound: 1, upperBound: 5}
+type queryRanges map[string]queryRange
+
+type queryRange struct {
+	key               string
+	lowerBound        interface{} // int || time.Time
+	includeLowerBound bool
+	upperBound        interface{} // int || time.Time
+	includeUpperBound bool
+}
+
+func lookForRanges(conditions []query.Condition) (ranges queryRanges, indexes []int) {
+	ranges = make(queryRanges)
+	for i, c := range conditions {
+		if isRangeOperation(c.Op) {
+			r, ok := ranges[c.Tag]
+			if !ok {
+				r = queryRange{key: c.Tag}
+			}
+			switch c.Op {
+			case query.OpGreater:
+				r.lowerBound = c.Operand
+			case query.OpGreaterEqual:
+				r.includeLowerBound = true
+				r.lowerBound = c.Operand
+			case query.OpLess:
+				r.upperBound = c.Operand
+			case query.OpLessEqual:
+				r.includeUpperBound = true
+				r.upperBound = c.Operand
+			}
+			ranges[c.Tag] = r
+			indexes = append(indexes, i)
+		}
+	}
+	return ranges, indexes
+}
+
+func isRangeOperation(op query.Operator) bool {
+	switch op {
+	case query.OpGreater, query.OpGreaterEqual, query.OpLess, query.OpLessEqual:
+		return true
+	default:
+		return false
+	}
+}
+
+func (txi *TxIndex) match(c query.Condition, startKey []byte) (hashes [][]byte) {
+	if c.Op == query.OpEqual {
+		it := txi.store.IteratorPrefix(startKey)
+		defer it.Release()
+		for it.Next() {
+			hashes = append(hashes, it.Value())
+		}
+	} else if c.Op == query.OpContains {
+		// XXX: doing full scan because startKey does not apply here
+		// For example, if startKey = "account.owner=an" and search query = "accoutn.owner CONSISTS an"
+		// we can't iterate with prefix "account.owner=an" because we might miss keys like "account.owner=Ulan"
+		it := txi.store.Iterator()
+		defer it.Release()
+		for it.Next() {
+			if !isTagKey(it.Key()) {
+				continue
+			}
+			if strings.Contains(extractValueFromKey(it.Key()), c.Operand.(string)) {
+				hashes = append(hashes, it.Value())
+			}
+		}
+	} else {
+		panic("other operators should be handled already")
+	}
+	return
+}
+
+func (txi *TxIndex) matchRange(r queryRange, startKey []byte) (hashes [][]byte) {
+	it := txi.store.IteratorPrefix(startKey)
+	defer it.Release()
+LOOP:
+	for it.Next() {
+		if !isTagKey(it.Key()) {
+			continue
+		}
+		if r.upperBound != nil {
+			// no other way to stop iterator other than checking for upperBound
+			switch (r.upperBound).(type) {
+			case int64:
+				v, err := strconv.ParseInt(extractValueFromKey(it.Key()), 10, 64)
+				if err == nil && v == r.upperBound {
+					if r.includeUpperBound {
+						hashes = append(hashes, it.Value())
+					}
+					break LOOP
+				}
+				// XXX: passing time in a ABCI Tags is not yet implemented
+				// case time.Time:
+				// 	v := strconv.ParseInt(extractValueFromKey(it.Key()), 10, 64)
+				// 	if v == r.upperBound {
+				// 		break
+				// 	}
+			}
+		}
+		hashes = append(hashes, it.Value())
+	}
+	return
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Keys
+
+func startKey(c query.Condition, height uint64) []byte {
+	var key string
+	if height > 0 {
+		key = fmt.Sprintf("%s/%v/%d", c.Tag, c.Operand, height)
+	} else {
+		key = fmt.Sprintf("%s/%v", c.Tag, c.Operand)
+	}
+	return []byte(key)
+}
+
+func startKeyForRange(r queryRange, height uint64) []byte {
+	if r.lowerBound == nil {
+		return []byte(fmt.Sprintf("%s", r.key))
+	}
+
+	var lowerBound interface{}
+	if r.includeLowerBound {
+		lowerBound = r.lowerBound
+	} else {
+		switch t := r.lowerBound.(type) {
+		case int64:
+			lowerBound = t + 1
+		case time.Time:
+			lowerBound = t.Unix() + 1
+		default:
+			panic("not implemented")
+		}
+	}
+	var key string
+	if height > 0 {
+		key = fmt.Sprintf("%s/%v/%d", r.key, lowerBound, height)
+	} else {
+		key = fmt.Sprintf("%s/%v", r.key, lowerBound)
+	}
+	return []byte(key)
+}
+
+func isTagKey(key []byte) bool {
+	return strings.Count(string(key), tagKeySeparator) == 3
+}
+
+func extractValueFromKey(key []byte) string {
+	parts := strings.SplitN(string(key), tagKeySeparator, 3)
+	return parts[1]
+}
+
+func keyForTag(tag *abci.KVPair, result *types.TxResult) []byte {
+	switch tag.ValueType {
+	case abci.KVPair_STRING:
+		return []byte(fmt.Sprintf("%s/%v/%d/%d", tag.Key, tag.ValueString, result.Height, result.Index))
+	case abci.KVPair_INT:
+		return []byte(fmt.Sprintf("%s/%v/%d/%d", tag.Key, tag.ValueInt, result.Height, result.Index))
+	// case abci.KVPair_TIME:
+	// 	return []byte(fmt.Sprintf("%s/%d/%d/%d", tag.Key, tag.ValueTime.Unix(), result.Height, result.Index))
+	default:
+		panic(fmt.Sprintf("Undefined value type: %v", tag.ValueType))
+	}
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Utils
+
+func intersect(as, bs [][]byte) [][]byte {
+	i := make([][]byte, 0, cmn.MinInt(len(as), len(bs)))
+	for _, a := range as {
+		for _, b := range bs {
+			if bytes.Equal(a, b) {
+				i = append(i, a)
+			}
+		}
+	}
+	return i
+}

state/txindex/kv/kv_test.go

@@ -1,6 +1,7 @@
 package kv
 
 import (
+	"fmt"
 	"io/ioutil"
 	"os"
 	"testing"
@@ -11,30 +12,145 @@ import (
 	"github.com/tendermint/tendermint/state/txindex"
 	"github.com/tendermint/tendermint/types"
 	db "github.com/tendermint/tmlibs/db"
+	"github.com/tendermint/tmlibs/pubsub/query"
 )
 
 func TestTxIndex(t *testing.T) {
-	indexer := &TxIndex{store: db.NewMemDB()}
+	indexer := NewTxIndex(db.NewMemDB())
 
 	tx := types.Tx("HELLO WORLD")
-	txResult := &types.TxResult{1, 0, tx, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: ""}}
+	txResult := &types.TxResult{1, 0, tx, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: "", Tags: []*abci.KVPair{}}}
 	hash := tx.Hash()
 
 	batch := txindex.NewBatch(1)
-	if err := batch.Add(*txResult); err != nil {
+	if err := batch.Add(txResult); err != nil {
 		t.Error(err)
 	}
 	err := indexer.AddBatch(batch)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	loadedTxResult, err := indexer.Get(hash)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	assert.Equal(t, txResult, loadedTxResult)
+
+	tx2 := types.Tx("BYE BYE WORLD")
+	txResult2 := &types.TxResult{1, 0, tx2, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: "", Tags: []*abci.KVPair{}}}
+	hash2 := tx2.Hash()
+
+	err = indexer.Index(txResult2)
+	require.NoError(t, err)
+
+	loadedTxResult2, err := indexer.Get(hash2)
+	require.NoError(t, err)
+	assert.Equal(t, txResult2, loadedTxResult2)
+}
+
+func TestTxSearch(t *testing.T) {
+	allowedTags := []string{"account.number", "account.owner", "account.date"}
+	indexer := NewTxIndex(db.NewMemDB(), IndexTags(allowedTags))
+
+	txResult := txResultWithTags([]*abci.KVPair{
+		{Key: "account.number", ValueType: abci.KVPair_INT, ValueInt: 1},
+		{Key: "account.owner", ValueType: abci.KVPair_STRING, ValueString: "Ivan"},
+		{Key: "not_allowed", ValueType: abci.KVPair_STRING, ValueString: "Vlad"},
+	})
+	hash := txResult.Tx.Hash()
+
+	err := indexer.Index(txResult)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		q             string
+		resultsLength int
+	}{
+		// search by hash
+		{fmt.Sprintf("tx.hash = '%X'", hash), 1},
+		// search by exact match (one tag)
+		{"account.number = 1", 1},
+		// search by exact match (two tags)
+		{"account.number = 1 AND account.owner = 'Ivan'", 1},
+		// search by exact match (two tags)
+		{"account.number = 1 AND account.owner = 'Vlad'", 0},
+		// search by range
+		{"account.number >= 1 AND account.number <= 5", 1},
+		// search by range (lower bound)
+		{"account.number >= 1", 1},
+		// search by range (upper bound)
+		{"account.number <= 5", 1},
+		// search using not allowed tag
+		{"not_allowed = 'boom'", 0},
+		// search for not existing tx result
+		{"account.number >= 2 AND account.number <= 5", 0},
+		// search using not existing tag
+		{"account.date >= TIME 2013-05-03T14:45:00Z", 0},
+		// search using CONTAINS
+		{"account.owner CONTAINS 'an'", 1},
+		// search using CONTAINS
+		{"account.owner CONTAINS 'Vlad'", 0},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.q, func(t *testing.T) {
+			results, err := indexer.Search(query.MustParse(tc.q))
+			assert.NoError(t, err)
+
+			assert.Len(t, results, tc.resultsLength)
+			if tc.resultsLength > 0 {
+				assert.Equal(t, []*types.TxResult{txResult}, results)
+			}
+		})
+	}
+}
+
+func TestTxSearchOneTxWithMultipleSameTagsButDifferentValues(t *testing.T) {
+	allowedTags := []string{"account.number"}
+	indexer := NewTxIndex(db.NewMemDB(), IndexTags(allowedTags))
+
+	txResult := txResultWithTags([]*abci.KVPair{
+		{Key: "account.number", ValueType: abci.KVPair_INT, ValueInt: 1},
+		{Key: "account.number", ValueType: abci.KVPair_INT, ValueInt: 2},
+	})
+
+	err := indexer.Index(txResult)
+	require.NoError(t, err)
+
+	results, err := indexer.Search(query.MustParse("account.number >= 1"))
+	assert.NoError(t, err)
+
+	assert.Len(t, results, 1)
+	assert.Equal(t, []*types.TxResult{txResult}, results)
+}
+
+func TestIndexAllTags(t *testing.T) {
+	indexer := NewTxIndex(db.NewMemDB(), IndexAllTags())
+
+	txResult := txResultWithTags([]*abci.KVPair{
+		abci.KVPairString("account.owner", "Ivan"),
+		abci.KVPairInt("account.number", 1),
+	})
+
+	err := indexer.Index(txResult)
+	require.NoError(t, err)
+
+	results, err := indexer.Search(query.MustParse("account.number >= 1"))
+	assert.NoError(t, err)
+	assert.Len(t, results, 1)
+	assert.Equal(t, []*types.TxResult{txResult}, results)
+
+	results, err = indexer.Search(query.MustParse("account.owner = 'Ivan'"))
+	assert.NoError(t, err)
+	assert.Len(t, results, 1)
+	assert.Equal(t, []*types.TxResult{txResult}, results)
+}
+
+func txResultWithTags(tags []*abci.KVPair) *types.TxResult {
+	tx := types.Tx("HELLO WORLD")
+	return &types.TxResult{1, 0, tx, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: "", Tags: tags}}
 }
 
 func benchmarkTxIndex(txsCount int, b *testing.B) {
 	tx := types.Tx("HELLO WORLD")
-	txResult := &types.TxResult{1, 0, tx, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: ""}}
+	txResult := &types.TxResult{1, 0, tx, abci.ResponseDeliverTx{Data: []byte{0}, Code: abci.CodeType_OK, Log: "", Tags: []*abci.KVPair{}}}
 
 	dir, err := ioutil.TempDir("", "tx_index_db")
 	if err != nil {
@@ -43,11 +159,11 @@ func benchmarkTxIndex(txsCount int, b *testing.B) {
 	defer os.RemoveAll(dir) // nolint: errcheck
 
 	store := db.NewDB("tx_index", "leveldb", dir)
-	indexer := &TxIndex{store: store}
+	indexer := NewTxIndex(store)
 
 	batch := txindex.NewBatch(txsCount)
 	for i := 0; i < txsCount; i++ {
-		if err := batch.Add(*txResult); err != nil {
+		if err := batch.Add(txResult); err != nil {
 			b.Fatal(err)
 		}
 		txResult.Index += 1

state/txindex/null/null.go

@@ -5,8 +5,11 @@ import (
 
 	"github.com/tendermint/tendermint/state/txindex"
 	"github.com/tendermint/tendermint/types"
+	"github.com/tendermint/tmlibs/pubsub/query"
 )
 
+var _ txindex.TxIndexer = (*TxIndex)(nil)
+
 // TxIndex acts as a /dev/null.
 type TxIndex struct{}
 
@@ -19,3 +22,12 @@ func (txi *TxIndex) Get(hash []byte) (*types.TxResult, error) {
 func (txi *TxIndex) AddBatch(batch *txindex.Batch) error {
 	return nil
 }
+
+// Index is a noop and always returns nil.
+func (txi *TxIndex) Index(result *types.TxResult) error {
+	return nil
+}
+
+func (txi *TxIndex) Search(q *query.Query) ([]*types.TxResult, error) {
+	return []*types.TxResult{}, nil
+}

types/event_bus.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 
+	abci "github.com/tendermint/abci/types"
 	cmn "github.com/tendermint/tmlibs/common"
 	"github.com/tendermint/tmlibs/log"
 	tmpubsub "github.com/tendermint/tmlibs/pubsub"
@@ -67,63 +68,101 @@ func (b *EventBus) Publish(eventType string, eventData TMEventData) error {
 
 //--- block, tx, and vote events
 
-func (b *EventBus) PublishEventNewBlock(block EventDataNewBlock) error {
-	return b.Publish(EventNewBlock, TMEventData{block})
+func (b *EventBus) PublishEventNewBlock(event EventDataNewBlock) error {
+	return b.Publish(EventNewBlock, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventNewBlockHeader(header EventDataNewBlockHeader) error {
-	return b.Publish(EventNewBlockHeader, TMEventData{header})
+func (b *EventBus) PublishEventNewBlockHeader(event EventDataNewBlockHeader) error {
+	return b.Publish(EventNewBlockHeader, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventVote(vote EventDataVote) error {
-	return b.Publish(EventVote, TMEventData{vote})
+func (b *EventBus) PublishEventVote(event EventDataVote) error {
+	return b.Publish(EventVote, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventTx(tx EventDataTx) error {
+// PublishEventTx publishes tx event with tags from Result. Note it will add
+// predefined tags (EventTypeKey, TxHashKey). Existing tags with the same names
+// will be overwritten.
+func (b *EventBus) PublishEventTx(event EventDataTx) error {
 	// no explicit deadline for publishing events
 	ctx := context.Background()
-	b.pubsub.PublishWithTags(ctx, TMEventData{tx}, map[string]interface{}{EventTypeKey: EventTx, TxHashKey: fmt.Sprintf("%X", tx.Tx.Hash())})
+
+	tags := make(map[string]interface{})
+
+	// validate and fill tags from tx result
+	for _, tag := range event.Result.Tags {
+		// basic validation
+		if tag.Key == "" {
+			b.Logger.Info("Got tag with an empty key (skipping)", "tag", tag, "tx", event.Tx)
+			continue
+		}
+
+		switch tag.ValueType {
+		case abci.KVPair_STRING:
+			tags[tag.Key] = tag.ValueString
+		case abci.KVPair_INT:
+			tags[tag.Key] = tag.ValueInt
+		}
+	}
+
+	// add predefined tags
+	logIfTagExists(EventTypeKey, tags, b.Logger)
+	tags[EventTypeKey] = EventTx
+
+	logIfTagExists(TxHashKey, tags, b.Logger)
+	tags[TxHashKey] = fmt.Sprintf("%X", event.Tx.Hash())
+
+	logIfTagExists(TxHeightKey, tags, b.Logger)
+	tags[TxHeightKey] = event.Height
+
+	b.pubsub.PublishWithTags(ctx, TMEventData{event}, tags)
 	return nil
 }
 
-func (b *EventBus) PublishEventProposalHeartbeat(ph EventDataProposalHeartbeat) error {
-	return b.Publish(EventProposalHeartbeat, TMEventData{ph})
+func (b *EventBus) PublishEventProposalHeartbeat(event EventDataProposalHeartbeat) error {
+	return b.Publish(EventProposalHeartbeat, TMEventData{event})
 }
 
 //--- EventDataRoundState events
 
-func (b *EventBus) PublishEventNewRoundStep(rs EventDataRoundState) error {
-	return b.Publish(EventNewRoundStep, TMEventData{rs})
+func (b *EventBus) PublishEventNewRoundStep(event EventDataRoundState) error {
+	return b.Publish(EventNewRoundStep, TMEventData{event})
+}
+
+func (b *EventBus) PublishEventTimeoutPropose(event EventDataRoundState) error {
+	return b.Publish(EventTimeoutPropose, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventTimeoutPropose(rs EventDataRoundState) error {
-	return b.Publish(EventTimeoutPropose, TMEventData{rs})
+func (b *EventBus) PublishEventTimeoutWait(event EventDataRoundState) error {
+	return b.Publish(EventTimeoutWait, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventTimeoutWait(rs EventDataRoundState) error {
-	return b.Publish(EventTimeoutWait, TMEventData{rs})
+func (b *EventBus) PublishEventNewRound(event EventDataRoundState) error {
+	return b.Publish(EventNewRound, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventNewRound(rs EventDataRoundState) error {
-	return b.Publish(EventNewRound, TMEventData{rs})
+func (b *EventBus) PublishEventCompleteProposal(event EventDataRoundState) error {
+	return b.Publish(EventCompleteProposal, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventCompleteProposal(rs EventDataRoundState) error {
-	return b.Publish(EventCompleteProposal, TMEventData{rs})
+func (b *EventBus) PublishEventPolka(event EventDataRoundState) error {
+	return b.Publish(EventPolka, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventPolka(rs EventDataRoundState) error {
-	return b.Publish(EventPolka, TMEventData{rs})
+func (b *EventBus) PublishEventUnlock(event EventDataRoundState) error {
+	return b.Publish(EventUnlock, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventUnlock(rs EventDataRoundState) error {
-	return b.Publish(EventUnlock, TMEventData{rs})
+func (b *EventBus) PublishEventRelock(event EventDataRoundState) error {
+	return b.Publish(EventRelock, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventRelock(rs EventDataRoundState) error {
-	return b.Publish(EventRelock, TMEventData{rs})
+func (b *EventBus) PublishEventLock(event EventDataRoundState) error {
+	return b.Publish(EventLock, TMEventData{event})
 }
 
-func (b *EventBus) PublishEventLock(rs EventDataRoundState) error {
-	return b.Publish(EventLock, TMEventData{rs})
+func logIfTagExists(tag string, tags map[string]interface{}, logger log.Logger) {
+	if value, ok := tags[tag]; ok {
+		logger.Error("Found predefined tag (value will be overwritten)", "tag", tag, "value", value)
+	}
 }

types/events.go

@@ -3,7 +3,6 @@ package types
 import (
 	"fmt"
 
-	abci "github.com/tendermint/abci/types"
 	"github.com/tendermint/go-wire/data"
 	tmpubsub "github.com/tendermint/tmlibs/pubsub"
 	tmquery "github.com/tendermint/tmlibs/pubsub/query"
@@ -110,12 +109,7 @@ type EventDataNewBlockHeader struct {
 
 // All txs fire EventDataTx
 type EventDataTx struct {
-	Height int           `json:"height"`
-	Tx     Tx            `json:"tx"`
-	Data   data.Bytes    `json:"data"`
-	Log    string        `json:"log"`
-	Code   abci.CodeType `json:"code"`
-	Error  string        `json:"error"` // this is redundant information for now
+	TxResult
 }
 
 type EventDataProposalHeartbeat struct {
@@ -142,10 +136,13 @@ type EventDataVote struct {
 
 const (
 	// EventTypeKey is a reserved key, used to specify event type in tags.
-	EventTypeKey = "tm.events.type"
+	EventTypeKey = "tm.event"
 	// TxHashKey is a reserved key, used to specify transaction's hash.
 	// see EventBus#PublishEventTx
 	TxHashKey = "tx.hash"
+	// TxHeightKey is a reserved key, used to specify transaction block's height.
+	// see EventBus#PublishEventTx
+	TxHeightKey = "tx.height"
 )
 
 var (
@@ -167,9 +164,10 @@ var (
 	EventQueryTimeoutWait       = queryForEvent(EventTimeoutWait)
 	EventQueryVote              = queryForEvent(EventVote)
 	EventQueryProposalHeartbeat = queryForEvent(EventProposalHeartbeat)
+	EventQueryTx                = queryForEvent(EventTx)
 )
 
-func EventQueryTx(tx Tx) tmpubsub.Query {
+func EventQueryTxFor(tx Tx) tmpubsub.Query {
 	return tmquery.MustParse(fmt.Sprintf("%s='%s' AND %s='%X'", EventTypeKey, EventTx, TxHashKey, tx.Hash()))
 }