feat: add TxStatus rpc endpoint (#1178)

## Description

Fixes - #1163

we've had some back and forth re this feature, and have decided to
implement this simple rpc endpoint as an interim solution while we
figure out and design an efficient way of querying transaction status
during its life cycle.

---------

consensus/replay_test.go

@@ -27,6 +27,7 @@ import (
 	mempl "github.com/cometbft/cometbft/mempool"
 	"github.com/cometbft/cometbft/privval"
 	cmtstate "github.com/cometbft/cometbft/proto/tendermint/state"
+	cmtstore "github.com/cometbft/cometbft/proto/tendermint/store"
 	cmtproto "github.com/cometbft/cometbft/proto/tendermint/types"
 	"github.com/cometbft/cometbft/proxy"
 	sm "github.com/cometbft/cometbft/state"
@@ -1221,6 +1222,7 @@ func (bs *mockBlockStore) LoadBlockMeta(height int64) *types.BlockMeta {
 func (bs *mockBlockStore) LoadBlockPart(height int64, index int) *types.Part { return nil }
 func (bs *mockBlockStore) SaveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit) {
 }
+func (bs *mockBlockStore) LoadTxInfo(hash []byte) *cmtstore.TxInfo { return &cmtstore.TxInfo{} }
 
 func (bs *mockBlockStore) LoadBlockCommit(height int64) *types.Commit {
 	return bs.commits[height-1]

go.sum

@@ -1452,6 +1452,8 @@ google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQ
 google.golang.org/protobuf v1.27.1/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
 google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
+google.golang.org/protobuf v1.32.0 h1:pPC6BG5ex8PDFnkbrGU3EixyhKcQ2aDuBS36lqK/C7I=
+google.golang.org/protobuf v1.32.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

light/proxy/routes.go

@@ -39,6 +39,7 @@ func RPCRoutes(c *lrpc.Client) map[string]*rpcserver.RPCFunc {
 		"consensus_params":     rpcserver.NewRPCFunc(makeConsensusParamsFunc(c), "height", rpcserver.Cacheable("height")),
 		"unconfirmed_txs":      rpcserver.NewRPCFunc(makeUnconfirmedTxsFunc(c), "limit"),
 		"num_unconfirmed_txs":  rpcserver.NewRPCFunc(makeNumUnconfirmedTxsFunc(c), ""),
+		"tx_status":            rpcserver.NewRPCFunc(makeTxStatusFunc(c), "hash"),
 
 		// tx broadcast API
 		"broadcast_tx_commit": rpcserver.NewRPCFunc(makeBroadcastTxCommitFunc(c), "tx"),
@@ -143,6 +144,14 @@ func makeBlockResultsFunc(c *lrpc.Client) rpcBlockResultsFunc {
 	}
 }
 
+type rpcTxStatusFunc func(ctx *rpctypes.Context, hash []byte) (*ctypes.ResultTxStatus, error)
+
+func makeTxStatusFunc(c *lrpc.Client) rpcTxStatusFunc {
+	return func(ctx *rpctypes.Context, hash []byte) (*ctypes.ResultTxStatus, error) {
+		return c.TxStatus(ctx.Context(), hash)
+	}
+}
+
 type rpcCommitFunc func(ctx *rpctypes.Context, height *int64) (*ctypes.ResultCommit, error)
 
 func makeCommitFunc(c *lrpc.Client) rpcCommitFunc {

light/rpc/client.go

@@ -487,6 +487,11 @@ func (c *Client) BlockResults(ctx context.Context, height *int64) (*ctypes.Resul
 	return res, nil
 }
 
+// TxStatus retrieves the status of the transaction given its hash.
+func (c *Client) TxStatus(ctx context.Context, hash []byte) (*ctypes.ResultTxStatus, error) {
+	return c.next.TxStatus(ctx, hash)
+}
+
 // Header fetches and verifies the header directly via the light client
 func (c *Client) Header(ctx context.Context, height *int64) (*ctypes.ResultHeader, error) {
 	lb, err := c.updateLightClientIfNeededTo(ctx, height)

proto/tendermint/store/types.proto

@@ -7,3 +7,9 @@ message BlockStoreState {
   int64 base   = 1;
   int64 height = 2;
 }
+
+// TxInfo describes the location of a tx inside a committed block.
+message TxInfo {
+  int64 height    = 1;
+  int64 index     = 2;
+}

rpc/client/http/http.go

@@ -516,6 +516,24 @@ func (c *baseRPCClient) DataCommitment(
 	return result, nil
 }
 
+func (c *baseRPCClient) TxStatus(
+	ctx context.Context,
+	hash []byte,
+) (*ctypes.ResultTxStatus, error) {
+	result := new(ctypes.ResultTxStatus)
+	params := map[string]interface{}{
+		"hash": hash,
+	}
+
+	_, err := c.caller.Call(ctx, "tx_status", params, result)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+
+}
+
 func (c *baseRPCClient) DataRootInclusionProof(
 	ctx context.Context,
 	height uint64,

rpc/client/interface.go

@@ -103,6 +103,9 @@ type SignClient interface {
 		page, perPage *int,
 		orderBy string,
 	) (*ctypes.ResultBlockSearch, error)
+
+	// TxStatus returns the transaction status for a given transaction hash.
+	TxStatus(ctx context.Context, hash []byte) (*ctypes.ResultTxStatus, error)
 }
 
 // HistoryClient provides access to data from genesis to now in large chunks.

rpc/client/local/local.go

@@ -239,6 +239,10 @@ func (c *Local) BlockSearch(
 	return core.BlockSearch(c.ctx, query, page, perPage, orderBy)
 }
 
+func (c *Local) TxStatus(ctx context.Context, hash []byte) (*ctypes.ResultTxStatus, error) {
+	return core.TxStatus(c.ctx, hash)
+}
+
 func (c *Local) BroadcastEvidence(ctx context.Context, ev types.Evidence) (*ctypes.ResultBroadcastEvidence, error) {
 	return core.BroadcastEvidence(c.ctx, ev)
 }

rpc/client/rpc_test.go

@@ -535,6 +535,35 @@ func TestBlockSearch(t *testing.T) {
 	require.Equal(t, blockCount, 0)
 
 }
+
+func TestTxStatus(t *testing.T) {
+	c := getHTTPClient()
+
+	// first we broadcast a few txs
+	var txHashes [][]byte
+	var txHeights []int64
+	for i := 0; i < 10; i++ {
+		_, _, tx := MakeTxKV()
+
+		result, err := c.BroadcastTxCommit(context.Background(), tx)
+		require.NoError(t, err)
+		txHashes = append(txHashes, result.Hash)
+		txHeights = append(txHeights, result.Height)
+	}
+
+	require.NoError(t, client.WaitForHeight(c, 5, nil))
+
+	// check the status of each transaction
+	for i, hash := range txHashes {
+		result, err := c.TxStatus(context.Background(), hash)
+		require.NoError(t, err)
+
+		expectedIndex := int64(0)
+		require.Equal(t, txHeights[i], result.Height)
+		require.Equal(t, expectedIndex, result.Index)
+	}
+}
+
 func TestTxSearch(t *testing.T) {
 	c := getHTTPClient()