feat: Query txs by signature and by address+seq (cosmos#9750)

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## Description

Closes: cosmos#9741 

<!-- Add a description of the changes that this PR introduces and the files that
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---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

CHANGELOG.md

@@ -41,6 +41,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * [\#9533](https://github.com/cosmos/cosmos-sdk/pull/9533) Added a new gRPC method, `DenomOwners`, in `x/bank` to query for all account holders of a specific denomination.
 * (bank) [\#9618](https://github.com/cosmos/cosmos-sdk/pull/9618) Update bank.Metadata: add URI and URIHash attributes.
+* [\#9750](https://github.com/cosmos/cosmos-sdk/pull/9750) Emit events for tx signature and sequence, so clients can now query txs by signature (`tx.signature='<base64_sig>'`) or by address and sequence combo (`tx.acc_seq='<addr>/<seq>'`).
 
 ### API Breaking Changes
 

types/events.go

@@ -223,6 +223,11 @@ func toBytes(i interface{}) []byte {
 
 // Common event types and attribute keys
 var (
+	EventTypeTx = "tx"
+
+	AttributeKeyAccountSequence = "acc_seq"
+	AttributeKeySignature       = "signature"
+
 	EventTypeMessage = "message"
 
 	AttributeKeyAction = "action"

x/auth/ante/sigverify.go

@@ -2,6 +2,7 @@ package ante
 
 import (
 	"bytes"
+	"encoding/base64"
 	"encoding/hex"
 	"fmt"
 
@@ -94,6 +95,34 @@ func (spkd SetPubKeyDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate b
 		spkd.ak.SetAccount(ctx, acc)
 	}
 
+	// Also emit the following events, so that txs can be indexed by these
+	// indices:
+	// - signature (via `tx.signature='<sig_as_base64>'`),
+	// - concat(address,"/",sequence) (via `tx.acc_seq='cosmos1abc...def/42'`).
+	sigs, err := sigTx.GetSignaturesV2()
+	if err != nil {
+		return ctx, err
+	}
+
+	var events sdk.Events
+	for i, sig := range sigs {
+		events = append(events, sdk.NewEvent(sdk.EventTypeTx,
+			sdk.NewAttribute(sdk.AttributeKeyAccountSequence, fmt.Sprintf("%s/%d", signers[i], sig.Sequence)),
+		))
+
+		sigBzs, err := signatureDataToBz(sig.Data)
+		if err != nil {
+			return ctx, err
+		}
+		for _, sigBz := range sigBzs {
+			events = append(events, sdk.NewEvent(sdk.EventTypeTx,
+				sdk.NewAttribute(sdk.AttributeKeySignature, base64.StdEncoding.EncodeToString(sigBz)),
+			))
+		}
+	}
+
+	ctx.EventManager().EmitEvents(events)
+
 	return next(ctx, tx, simulate)
 }
 
@@ -447,3 +476,42 @@ func CountSubKeys(pub cryptotypes.PubKey) int {
 
 	return numKeys
 }
+
+// signatureDataToBz converts a SignatureData into raw bytes signature.
+// For SingleSignatureData, it returns the signature raw bytes.
+// For MultiSignatureData, it returns an array of all individual signatures,
+// as well as the aggregated signature.
+func signatureDataToBz(data signing.SignatureData) ([][]byte, error) {
+	if data == nil {
+		return nil, fmt.Errorf("got empty SignatureData")
+	}
+
+	switch data := data.(type) {
+	case *signing.SingleSignatureData:
+		return [][]byte{data.Signature}, nil
+	case *signing.MultiSignatureData:
+		sigs := [][]byte{}
+		var err error
+
+		for _, d := range data.Signatures {
+			nestedSigs, err := signatureDataToBz(d)
+			if err != nil {
+				return nil, err
+			}
+			sigs = append(sigs, nestedSigs...)
+		}
+
+		multisig := cryptotypes.MultiSignature{
+			Signatures: sigs,
+		}
+		aggregatedSig, err := multisig.Marshal()
+		if err != nil {
+			return nil, err
+		}
+		sigs = append(sigs, aggregatedSig)
+
+		return sigs, nil
+	default:
+		return nil, sdkerrors.ErrInvalidType.Wrapf("unexpected signature data type %T", data)
+	}
+}

x/auth/client/cli/query.go

@@ -10,6 +10,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/types/query"
 	"github.com/cosmos/cosmos-sdk/version"
 	authtx "github.com/cosmos/cosmos-sdk/x/auth/tx"
@@ -18,6 +19,11 @@ import (
 
 const (
 	flagEvents = "events"
+	flagType   = "type"
+
+	typeHash   = "hash"
+	typeAccSeq = "acc_seq"
+	typeSig    = "signature"
 
 	eventFormat = "{eventType}.{eventAttribute}={value}"
 )
@@ -210,28 +216,110 @@ $ %s query txs --%s 'message.sender=cosmos1...&message.action=withdraw_delegator
 // QueryTxCmd implements the default command for a tx query.
 func QueryTxCmd() *cobra.Command {
 	cmd := &cobra.Command{
-		Use:   "tx [hash]",
-		Short: "Query for a transaction by hash in a committed block",
-		Args:  cobra.ExactArgs(1),
+		Use:   "tx --type=[hash|acc_seq|signature] [hash|acc_seq|signature]",
+		Short: "Query for a transaction by hash, addr++seq combination or signature in a committed block",
+		Long: strings.TrimSpace(fmt.Sprintf(`
+Example:
+$ %s query tx <hash>
+$ %s query tx --%s=%s <addr>:<sequence>
+$ %s query tx --%s=%s <sig1_base64,sig2_base64...>
+`,
+			version.AppName,
+			version.AppName, flagType, typeAccSeq,
+			version.AppName, flagType, typeSig)),
+		Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			clientCtx, err := client.GetClientQueryContext(cmd)
 			if err != nil {
 				return err
 			}
-			output, err := authtx.QueryTx(clientCtx, args[0])
-			if err != nil {
-				return err
-			}
 
-			if output.Empty() {
-				return fmt.Errorf("no transaction found with hash %s", args[0])
-			}
+			typ, _ := cmd.Flags().GetString(flagType)
+
+			switch typ {
+			case typeHash:
+				{
+					if args[0] == "" {
+						return fmt.Errorf("argument should be a tx hash")
+					}
+
+					// If hash is given, then query the tx by hash.
+					output, err := authtx.QueryTx(clientCtx, args[0])
+					if err != nil {
+						return err
+					}
 
-			return clientCtx.PrintProto(output)
+					if output.Empty() {
+						return fmt.Errorf("no transaction found with hash %s", args[0])
+					}
+
+					return clientCtx.PrintProto(output)
+				}
+			case typeSig:
+				{
+					sigParts, err := parseSigArgs(args)
+					if err != nil {
+						return err
+					}
+					tmEvents := make([]string, len(sigParts))
+					for i, sig := range sigParts {
+						tmEvents[i] = fmt.Sprintf("%s.%s='%s'", sdk.EventTypeTx, sdk.AttributeKeySignature, sig)
+					}
+
+					txs, err := authtx.QueryTxsByEvents(clientCtx, tmEvents, query.DefaultPage, query.DefaultLimit, "")
+					if err != nil {
+						return err
+					}
+					if len(txs.Txs) == 0 {
+						return fmt.Errorf("found no txs matching given signatures")
+					}
+					if len(txs.Txs) > 1 {
+						// This case means there's a bug somewhere else in the code. Should not happen.
+						return errors.ErrLogic.Wrapf("found %d txs matching given signatures", len(txs.Txs))
+					}
+
+					return clientCtx.PrintProto(txs.Txs[0])
+				}
+			case typeAccSeq:
+				{
+					if args[0] == "" {
+						return fmt.Errorf("`acc_seq` type takes an argument '<addr>/<seq>'")
+					}
+
+					tmEvents := []string{
+						fmt.Sprintf("%s.%s='%s'", sdk.EventTypeTx, sdk.AttributeKeyAccountSequence, args[0]),
+					}
+					txs, err := authtx.QueryTxsByEvents(clientCtx, tmEvents, query.DefaultPage, query.DefaultLimit, "")
+					if err != nil {
+						return err
+					}
+					if len(txs.Txs) == 0 {
+						return fmt.Errorf("found no txs matching given address and sequence combination")
+					}
+					if len(txs.Txs) > 1 {
+						// This case means there's a bug somewhere else in the code. Should not happen.
+						return fmt.Errorf("found %d txs matching given address and sequence combination", len(txs.Txs))
+					}
+
+					return clientCtx.PrintProto(txs.Txs[0])
+				}
+			default:
+				return fmt.Errorf("unknown --%s value %s", flagType, typ)
+			}
 		},
 	}
 
 	flags.AddQueryFlagsToCmd(cmd)
+	cmd.Flags().String(flagType, typeHash, fmt.Sprintf("The type to be used when querying tx, can be one of \"%s\", \"%s\", \"%s\"", typeHash, typeAccSeq, typeSig))
 
 	return cmd
 }
+
+// parseSigArgs parses comma-separated signatures from the CLI arguments.
+func parseSigArgs(args []string) ([]string, error) {
+	if len(args) != 1 || args[0] == "" {
+		return nil, fmt.Errorf("argument should be comma-separated signatures")
+	}
+
+	return strings.Split(args[0], ","), nil
+}

x/auth/client/cli/query_test.go

@@ -0,0 +1,32 @@
+package cli
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseSigs(t *testing.T) {
+	cases := []struct {
+		name       string
+		args       []string
+		expErr     bool
+		expNumSigs int
+	}{
+		{"no args", []string{}, true, 0},
+		{"empty args", []string{""}, true, 0},
+		{"too many args", []string{"foo", "bar"}, true, 0},
+		{"1 sig", []string{"foo"}, false, 1},
+		{"3 sigs", []string{"foo,bar,baz"}, false, 3},
+	}
+
+	for _, tc := range cases {
+		sigs, err := parseSigArgs(tc.args)
+		if tc.expErr {
+			require.Error(t, err)
+		} else {
+			require.NoError(t, err)
+			require.Equal(t, tc.expNumSigs, len(sigs))
+		}
+	}
+}