Merge pull request #4228 from carlaKC/txdetails-labeltxrpc

walletrpc: add LabelTransaction endpoint to retrospectively label txns

cmd/lncli/walletrpc_active.go

@@ -28,6 +28,7 @@ func walletCommands() []cli.Command {
 				bumpFeeCommand,
 				bumpCloseFeeCommand,
 				listSweepsCommand,
+				labelTxCommand,
 			},
 		},
 	}
@@ -340,3 +341,58 @@ func listSweeps(ctx *cli.Context) error {
 
 	return nil
 }
+
+var labelTxCommand = cli.Command{
+	Name:      "labeltx",
+	Usage:     "adds a label to a transaction",
+	ArgsUsage: "txid label",
+	Description: `
+	Add a label to a transaction. If the transaction already has a label, 
+	this call will fail unless the overwrite option is set. The label is 
+	limited to 500 characters. Note that multi word labels must be contained
+	in quotation marks ("").
+	`,
+	Flags: []cli.Flag{
+		cli.BoolFlag{
+			Name:  "overwrite",
+			Usage: "set to overwrite existing labels",
+		},
+	},
+	Action: actionDecorator(labelTransaction),
+}
+
+func labelTransaction(ctx *cli.Context) error {
+	// Display the command's help message if we do not have the expected
+	// number of arguments/flags.
+	if ctx.NArg() != 2 {
+		return cli.ShowCommandHelp(ctx, "labeltx")
+	}
+
+	// Get the transaction id and check that it is a valid hash.
+	txid := ctx.Args().Get(0)
+	hash, err := chainhash.NewHashFromStr(txid)
+	if err != nil {
+		return err
+	}
+
+	label := ctx.Args().Get(1)
+
+	walletClient, cleanUp := getWalletClient(ctx)
+	defer cleanUp()
+
+	ctxb := context.Background()
+	_, err = walletClient.LabelTransaction(
+		ctxb, &walletrpc.LabelTransactionRequest{
+			Txid:      hash[:],
+			Label:     label,
+			Overwrite: ctx.Bool("overwrite"),
+		},
+	)
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("Transaction: %v labelled with: %v\n", txid, label)
+
+	return nil
+}

lnrpc/walletrpc/walletkit.pb.go

@@ -997,6 +997,95 @@ func (m *ListSweepsResponse_TransactionIDs) GetTransactionIds() []string {
 	return nil
 }
 
+type LabelTransactionRequest struct {
+	// The txid of the transaction to label.
+	Txid []byte `protobuf:"bytes,1,opt,name=txid,proto3" json:"txid,omitempty"`
+	// The label to add to the transaction, limited to 500 characters.
+	Label string `protobuf:"bytes,2,opt,name=label,proto3" json:"label,omitempty"`
+	// Whether to overwrite the existing label, if it is present.
+	Overwrite            bool     `protobuf:"varint,3,opt,name=overwrite,proto3" json:"overwrite,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *LabelTransactionRequest) Reset()         { *m = LabelTransactionRequest{} }
+func (m *LabelTransactionRequest) String() string { return proto.CompactTextString(m) }
+func (*LabelTransactionRequest) ProtoMessage()    {}
+func (*LabelTransactionRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_6cc6942ac78249e5, []int{16}
+}
+
+func (m *LabelTransactionRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_LabelTransactionRequest.Unmarshal(m, b)
+}
+func (m *LabelTransactionRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_LabelTransactionRequest.Marshal(b, m, deterministic)
+}
+func (m *LabelTransactionRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_LabelTransactionRequest.Merge(m, src)
+}
+func (m *LabelTransactionRequest) XXX_Size() int {
+	return xxx_messageInfo_LabelTransactionRequest.Size(m)
+}
+func (m *LabelTransactionRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_LabelTransactionRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_LabelTransactionRequest proto.InternalMessageInfo
+
+func (m *LabelTransactionRequest) GetTxid() []byte {
+	if m != nil {
+		return m.Txid
+	}
+	return nil
+}
+
+func (m *LabelTransactionRequest) GetLabel() string {
+	if m != nil {
+		return m.Label
+	}
+	return ""
+}
+
+func (m *LabelTransactionRequest) GetOverwrite() bool {
+	if m != nil {
+		return m.Overwrite
+	}
+	return false
+}
+
+type LabelTransactionResponse struct {
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *LabelTransactionResponse) Reset()         { *m = LabelTransactionResponse{} }
+func (m *LabelTransactionResponse) String() string { return proto.CompactTextString(m) }
+func (*LabelTransactionResponse) ProtoMessage()    {}
+func (*LabelTransactionResponse) Descriptor() ([]byte, []int) {
+	return fileDescriptor_6cc6942ac78249e5, []int{17}
+}
+
+func (m *LabelTransactionResponse) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_LabelTransactionResponse.Unmarshal(m, b)
+}
+func (m *LabelTransactionResponse) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_LabelTransactionResponse.Marshal(b, m, deterministic)
+}
+func (m *LabelTransactionResponse) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_LabelTransactionResponse.Merge(m, src)
+}
+func (m *LabelTransactionResponse) XXX_Size() int {
+	return xxx_messageInfo_LabelTransactionResponse.Size(m)
+}
+func (m *LabelTransactionResponse) XXX_DiscardUnknown() {
+	xxx_messageInfo_LabelTransactionResponse.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_LabelTransactionResponse proto.InternalMessageInfo
+
 func init() {
 	proto.RegisterEnum("walletrpc.WitnessType", WitnessType_name, WitnessType_value)
 	proto.RegisterType((*KeyReq)(nil), "walletrpc.KeyReq")
@@ -1016,87 +1105,93 @@ func init() {
 	proto.RegisterType((*ListSweepsRequest)(nil), "walletrpc.ListSweepsRequest")
 	proto.RegisterType((*ListSweepsResponse)(nil), "walletrpc.ListSweepsResponse")
 	proto.RegisterType((*ListSweepsResponse_TransactionIDs)(nil), "walletrpc.ListSweepsResponse.TransactionIDs")
+	proto.RegisterType((*LabelTransactionRequest)(nil), "walletrpc.LabelTransactionRequest")
+	proto.RegisterType((*LabelTransactionResponse)(nil), "walletrpc.LabelTransactionResponse")
 }
 
 func init() { proto.RegisterFile("walletrpc/walletkit.proto", fileDescriptor_6cc6942ac78249e5) }
 
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-	0x89, 0x43, 0x38, 0x88, 0xe3, 0x0a, 0x72, 0x95, 0x5e, 0xc2, 0x61, 0xcf, 0xf2, 0x58, 0xa2, 0x32,
+	0xd8, 0x10, 0x2b, 0xb1, 0x0d, 0x5b, 0x49, 0x5c, 0x61, 0xae, 0xd2, 0x0b, 0xd8, 0xee, 0xd9, 0x3e,
-	0xa8, 0x0a, 0xfb, 0x9f, 0x08, 0x1d, 0x39, 0x1e, 0xe1, 0xc1, 0x66, 0xd5, 0xe8, 0x29, 0xfd, 0xb9,
+	0x4b, 0x55, 0x06, 0xeb, 0xb0, 0xf9, 0x91, 0xd0, 0x81, 0xeb, 0x13, 0x1e, 0x6c, 0x5e, 0x8d, 0x8f,
-	0x0b, 0x48, 0xe4, 0x87, 0x15, 0xeb, 0x41, 0x85, 0xad, 0x17, 0x10, 0x36, 0x09, 0x33, 0xac, 0xa9,
+	0xd2, 0xdf, 0xeb, 0x80, 0x22, 0x3e, 0xaa, 0x58, 0x0f, 0x6a, 0x6c, 0xb1, 0x80, 0x0c, 0x8b, 0x30,
-	0x17, 0x66, 0xfa, 0x34, 0xcc, 0x54, 0x58, 0x51, 0xad, 0x80, 0xd0, 0x7e, 0xa2, 0x22, 0xb6, 0x25,
+	0xd3, 0x1e, 0xfb, 0x51, 0xa6, 0x8f, 0xa3, 0x4c, 0x85, 0x15, 0xd5, 0x0e, 0x01, 0x9d, 0x47, 0x2a,
-	0x45, 0x43, 0x38, 0x10, 0xad, 0x59, 0xa6, 0xc7, 0x6b, 0x90, 0xbf, 0x7e, 0x21, 0x34, 0x60, 0x3b,
+	0xb2, 0x15, 0x29, 0xde, 0xc0, 0x96, 0xc8, 0x66, 0x5b, 0x3e, 0xaf, 0x41, 0xf1, 0xf4, 0xb9, 0xd0,
-	0x0a, 0xd1, 0x41, 0xa7, 0xe5, 0x1b, 0x2f, 0x09, 0x66, 0x3a, 0xa6, 0x57, 0x7b, 0x0d, 0xa5, 0x24,
+	0x80, 0xd5, 0x28, 0x44, 0x07, 0x97, 0xed, 0x80, 0xbc, 0x22, 0xd0, 0x5c, 0x5a, 0x7e, 0xe3, 0x15,
-	0x07, 0x7d, 0xbb, 0xed, 0xca, 0xef, 0x75, 0x6e, 0x53, 0xf5, 0x26, 0x0b, 0x99, 0x60, 0x16, 0xbe,
+	0x54, 0xd2, 0x18, 0xfc, 0x6e, 0xd5, 0x55, 0xd0, 0xeb, 0xc2, 0xb2, 0xe9, 0x79, 0x1e, 0x72, 0xe1,
-	0xfb, 0x9c, 0x82, 0xbc, 0xf0, 0x39, 0xa2, 0x0a, 0x1c, 0xbc, 0xed, 0x77, 0xfb, 0xca, 0xb0, 0x8f,
+	0x2c, 0x48, 0x26, 0xec, 0xf7, 0x82, 0x6d, 0x24, 0x30, 0xc5, 0x75, 0x43, 0xd8, 0x60, 0x33, 0xdb,
-	0x87, 0x1d, 0xbd, 0x2f, 0x6b, 0x5a, 0xf9, 0x09, 0xaa, 0xc2, 0x51, 0x53, 0xb9, 0xbb, 0xeb, 0xe8,
+	0x8a, 0xd6, 0x10, 0xff, 0xfe, 0xfc, 0xd6, 0xc5, 0x03, 0x28, 0xb8, 0x1f, 0x09, 0x9d, 0x52, 0x3b,
-	0x77, 0x72, 0x5f, 0xc7, 0x7a, 0xe7, 0x4e, 0xc6, 0x3d, 0xa5, 0xd9, 0x2d, 0xef, 0xa0, 0x53, 0xa8,
+	0x6a, 0x5f, 0x5e, 0x5d, 0x08, 0xa4, 0x06, 0xd4, 0x57, 0x5d, 0x84, 0x49, 0x7e, 0xff, 0x29, 0x03,
-	0x08, 0x48, 0x5f, 0xc1, 0x2d, 0xb9, 0xd7, 0x78, 0x5f, 0xde, 0x45, 0xc7, 0x70, 0x28, 0x00, 0xaa,
+	0x45, 0x61, 0x1b, 0x60, 0x0d, 0xb6, 0xde, 0xf4, 0xbb, 0x7d, 0xe5, 0xa6, 0x6f, 0xdc, 0x5c, 0xea,
-	0xfc, 0x4e, 0xe9, 0xca, 0xe5, 0x94, 0xcf, 0x6f, 0xeb, 0xbd, 0x26, 0x56, 0x6e, 0x6f, 0x65, 0x55,
+	0x7d, 0x59, 0xd3, 0xaa, 0x8f, 0xb0, 0x0e, 0x3b, 0x2d, 0xe5, 0xea, 0xea, 0x52, 0xbf, 0x92, 0xfb,
-	0x6e, 0x45, 0xc0, 0x9e, 0xef, 0x82, 0x03, 0x8d, 0x66, 0x53, 0x1e, 0xe8, 0x6b, 0x24, 0x8d, 0xbe,
+	0xba, 0xa1, 0x5f, 0x5e, 0xc9, 0x46, 0x4f, 0x69, 0x75, 0xab, 0x6b, 0xb8, 0x0f, 0x35, 0x41, 0xd3,
-	0x86, 0xff, 0x27, 0x54, 0x7c, 0xf7, 0xca, 0x5b, 0x1d, 0x6b, 0x72, 0x53, 0xe9, 0xb7, 0x70, 0x4f,
+	0x57, 0x8c, 0xb6, 0xdc, 0x3b, 0x7b, 0x57, 0x5d, 0xc7, 0x5d, 0xd8, 0x16, 0x14, 0xaa, 0xfc, 0x56,
-	0x7e, 0x27, 0xf7, 0xca, 0x19, 0xf4, 0x0d, 0x48, 0x49, 0x03, 0xda, 0xdb, 0x66, 0x53, 0xd6, 0xb4,
+	0xe9, 0xca, 0xd5, 0x4c, 0x80, 0xef, 0xe8, 0xbd, 0x96, 0xa1, 0x5c, 0x5c, 0xc8, 0xaa, 0xdc, 0x8e,
-	0x24, 0x6f, 0x1f, 0x9d, 0xc3, 0xb3, 0x8d, 0x08, 0xee, 0x14, 0x5d, 0x8e, 0xac, 0x96, 0xb3, 0xe8,
+	0x15, 0x1b, 0x81, 0x0b, 0xae, 0x38, 0x6b, 0xb5, 0xe4, 0x6b, 0x7d, 0xa1, 0xc9, 0xe2, 0x37, 0xf0,
-	0x02, 0xce, 0x36, 0x23, 0xe1, 0x8c, 0xd0, 0x5e, 0x39, 0x87, 0xce, 0xa0, 0xca, 0x19, 0xa2, 0xe5,
+	0x75, 0xca, 0x24, 0x70, 0xaf, 0xbc, 0xd1, 0x0d, 0x4d, 0x6e, 0x29, 0xfd, 0xb6, 0xd1, 0x93, 0xdf,
-	0x28, 0x5e, 0x40, 0x47, 0x50, 0x0e, 0x2b, 0x87, 0xbb, 0xf2, 0x7b, 0xdc, 0x6e, 0x68, 0xed, 0x72,
+	0xca, 0xbd, 0x6a, 0x0e, 0xbf, 0x05, 0x29, 0x4d, 0xa0, 0xbd, 0x69, 0xb5, 0x64, 0x4d, 0x4b, 0xe3,
-	0x1e, 0x3d, 0x83, 0xd3, 0xbe, 0xac, 0xf9, 0xe6, 0xb6, 0xc0, 0xc2, 0x46, 0xb1, 0x1a, 0xfd, 0x66,
+	0x36, 0xf1, 0x10, 0x9e, 0x2c, 0x45, 0x70, 0xa5, 0xe8, 0x72, 0xcc, 0x5a, 0xcd, 0xe3, 0x11, 0x1c,
-	0x5b, 0x51, 0xcb, 0xc5, 0xeb, 0xbf, 0xd2, 0x90, 0x1b, 0xf2, 0x11, 0xe9, 0x5a, 0x0c, 0xbd, 0x81,
+	0x2c, 0x47, 0xc2, 0x11, 0x11, 0x5f, 0xb5, 0x80, 0x07, 0x50, 0xe7, 0x08, 0x91, 0x39, 0x8e, 0x17,
-	0x62, 0x8b, 0x50, 0xeb, 0x13, 0xe9, 0x93, 0x25, 0xeb, 0x92, 0x15, 0x3a, 0x14, 0xe6, 0x27, 0x38,
+	0x70, 0x07, 0xaa, 0x51, 0xe5, 0x8c, 0xae, 0xfc, 0xce, 0xe8, 0x9c, 0x69, 0x9d, 0x6a, 0x11, 0x9f,
-	0xdb, 0xb5, 0x93, 0xf8, 0x02, 0x75, 0xc9, 0xaa, 0x45, 0xbc, 0x31, 0xb5, 0x5c, 0xe6, 0x50, 0xf4,
+	0xc0, 0x7e, 0x5f, 0xd6, 0x02, 0xba, 0x15, 0x65, 0x69, 0xa9, 0x58, 0x67, 0xfd, 0x56, 0x47, 0x51,
-	0x33, 0xe4, 0x02, 0x5d, 0x5f, 0xaf, 0x22, 0x92, 0x7a, 0xce, 0xd8, 0x60, 0x0e, 0x7d, 0x54, 0xf3,
+	0xab, 0xe5, 0xd3, 0x7f, 0xb3, 0x50, 0xb8, 0xe1, 0x13, 0xda, 0xb5, 0x19, 0xbe, 0x86, 0x72, 0x9b,
-	0x17, 0xc8, 0xfa, 0xfe, 0xfc, 0xa3, 0x8d, 0xc4, 0x15, 0x2e, 0x1c, 0xf5, 0xda, 0xe9, 0x96, 0x3c,
+	0x50, 0xfb, 0x23, 0xe9, 0x93, 0x19, 0xeb, 0x92, 0x39, 0x6e, 0x0b, 0xe3, 0x1b, 0xbe, 0x1a, 0x1a,
-	0xfc, 0x90, 0xda, 0x80, 0xc2, 0x6b, 0x2c, 0x1e, 0x74, 0xd1, 0x8c, 0x20, 0xaf, 0xd5, 0xc4, 0x85,
+	0x7b, 0xc9, 0x05, 0xd8, 0x25, 0xf3, 0x36, 0xf1, 0x87, 0xd4, 0xf6, 0x98, 0x4b, 0xf1, 0x17, 0x28,
-	0xb4, 0x71, 0xc4, 0x7b, 0x90, 0x17, 0x6e, 0x25, 0x7a, 0x2e, 0x50, 0xb7, 0xef, 0x76, 0xed, 0x7f,
+	0x84, 0xb6, 0x81, 0x5d, 0x4d, 0x04, 0xf5, 0xdc, 0xa1, 0xc9, 0x5c, 0xfa, 0xa0, 0xe5, 0xaf, 0x90,
-	0x8f, 0xc1, 0x6b, 0x6b, 0xc2, 0x51, 0x4c, 0x58, 0xdb, 0xbe, 0xb1, 0x09, 0x6b, 0xff, 0x76, 0x4b,
+	0x0f, 0xfc, 0x05, 0x6f, 0x06, 0x14, 0x6f, 0x10, 0xe1, 0x4d, 0xd1, 0xd8, 0x5f, 0x91, 0x47, 0xff,
-	0x55, 0x28, 0x26, 0x36, 0x2f, 0x3a, 0x7f, 0x64, 0xb3, 0xc6, 0xf1, 0x5d, 0x3c, 0x4e, 0x08, 0x6d,
+	0xe3, 0x0e, 0x60, 0xf4, 0x18, 0x10, 0xdf, 0x13, 0x22, 0x8d, 0x20, 0x6f, 0x34, 0xc4, 0x7d, 0xb8,
-	0xfe, 0x06, 0xfb, 0xe1, 0x6e, 0x43, 0x4f, 0x05, 0x72, 0x72, 0x0f, 0x27, 0x2a, 0xb6, 0xb1, 0x0a,
+	0xf4, 0x86, 0xe8, 0x41, 0x51, 0xb8, 0xaa, 0xf1, 0xa9, 0x00, 0x5d, 0x7d, 0x36, 0x34, 0xbe, 0x7a,
-	0x51, 0x07, 0x60, 0xbd, 0x54, 0xd0, 0xd9, 0x23, 0xbb, 0x26, 0xb0, 0xf3, 0xfc, 0x8b, 0x9b, 0xe8,
+	0x48, 0xbd, 0x60, 0x13, 0xee, 0xe4, 0x14, 0xdb, 0xea, 0x15, 0x9f, 0x62, 0xfb, 0xdc, 0x55, 0xae,
-	0xe6, 0x87, 0x3f, 0xae, 0x26, 0x16, 0xbb, 0x9f, 0x8f, 0xea, 0x63, 0x67, 0x76, 0x35, 0xf5, 0xaf,
+	0x42, 0x39, 0xb5, 0xf8, 0xf1, 0xf0, 0x81, 0xc5, 0x9e, 0xc4, 0x77, 0xf4, 0x30, 0x20, 0xe2, 0xfc,
-	0xa0, 0x6d, 0xd9, 0x13, 0x9b, 0xb0, 0x85, 0x43, 0x1f, 0xae, 0xa6, 0xb6, 0x79, 0xc5, 0x77, 0xe2,
+	0x1d, 0x36, 0xa3, 0xd5, 0x8a, 0x8f, 0x05, 0x70, 0xfa, 0x1a, 0x48, 0x55, 0x6c, 0x69, 0x13, 0xe3,
-	0x55, 0x6c, 0x65, 0x94, 0xe1, 0xff, 0x50, 0xbe, 0xfa, 0x27, 0x00, 0x00, 0xff, 0xff, 0xde, 0x94,
+	0x25, 0xc0, 0x62, 0xa7, 0xe1, 0xc1, 0x03, 0xab, 0x2e, 0xe4, 0x79, 0xfa, 0xc5, 0x45, 0x88, 0x7f,
-	0x5b, 0x29, 0x99, 0x0a, 0x00, 0x00,
+	0x41, 0x75, 0x79, 0x7f, 0xa0, 0x24, 0x9a, 0x7c, 0x7e, 0x7f, 0x35, 0x9e, 0x7d, 0x11, 0x13, 0x92,
+	0x9f, 0xff, 0xf8, 0xe7, 0xc9, 0xc8, 0x66, 0xb7, 0x93, 0x41, 0x73, 0xe8, 0xde, 0x9f, 0x8c, 0x83,
+	0x1b, 0xde, 0xb1, 0x9d, 0x91, 0x43, 0xd8, 0xd4, 0xa5, 0x77, 0x27, 0x63, 0xc7, 0x3a, 0xe1, 0xfb,
+	0xfe, 0x24, 0xe1, 0x1a, 0xe4, 0xf8, 0x63, 0xf9, 0xe5, 0x7f, 0x01, 0x00, 0x00, 0xff, 0xff, 0xb5,
+	0xeb, 0x99, 0xb8, 0x75, 0x0b, 0x00, 0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -1181,6 +1276,12 @@ type WalletKitClient interface {
 	//Note that these sweeps may not be confirmed yet, as we record sweeps on
 	//broadcast, not confirmation.
 	ListSweeps(ctx context.Context, in *ListSweepsRequest, opts ...grpc.CallOption) (*ListSweepsResponse, error)
+	//
+	//LabelTransaction adds a label to a transaction. If the transaction already
+	//has a label the call will fail unless the overwrite bool is set. This will
+	//overwrite the exiting transaction label. Labels must not be empty, and
+	//cannot exceed 500 characters.
+	LabelTransaction(ctx context.Context, in *LabelTransactionRequest, opts ...grpc.CallOption) (*LabelTransactionResponse, error)
 }
 
 type walletKitClient struct {
@@ -1272,6 +1373,15 @@ func (c *walletKitClient) ListSweeps(ctx context.Context, in *ListSweepsRequest,
 	return out, nil
 }
 
+func (c *walletKitClient) LabelTransaction(ctx context.Context, in *LabelTransactionRequest, opts ...grpc.CallOption) (*LabelTransactionResponse, error) {
+	out := new(LabelTransactionResponse)
+	err := c.cc.Invoke(ctx, "/walletrpc.WalletKit/LabelTransaction", in, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // WalletKitServer is the server API for WalletKit service.
 type WalletKitServer interface {
 	//
@@ -1344,6 +1454,12 @@ type WalletKitServer interface {
 	//Note that these sweeps may not be confirmed yet, as we record sweeps on
 	//broadcast, not confirmation.
 	ListSweeps(context.Context, *ListSweepsRequest) (*ListSweepsResponse, error)
+	//
+	//LabelTransaction adds a label to a transaction. If the transaction already
+	//has a label the call will fail unless the overwrite bool is set. This will
+	//overwrite the exiting transaction label. Labels must not be empty, and
+	//cannot exceed 500 characters.
+	LabelTransaction(context.Context, *LabelTransactionRequest) (*LabelTransactionResponse, error)
 }
 
 func RegisterWalletKitServer(s *grpc.Server, srv WalletKitServer) {
@@ -1512,6 +1628,24 @@ func _WalletKit_ListSweeps_Handler(srv interface{}, ctx context.Context, dec fun
 	return interceptor(ctx, in, info, handler)
 }
 
+func _WalletKit_LabelTransaction_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(LabelTransactionRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(WalletKitServer).LabelTransaction(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/walletrpc.WalletKit/LabelTransaction",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(WalletKitServer).LabelTransaction(ctx, req.(*LabelTransactionRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 var _WalletKit_serviceDesc = grpc.ServiceDesc{
 	ServiceName: "walletrpc.WalletKit",
 	HandlerType: (*WalletKitServer)(nil),
@@ -1552,6 +1686,10 @@ var _WalletKit_serviceDesc = grpc.ServiceDesc{
 			MethodName: "ListSweeps",
 			Handler:    _WalletKit_ListSweeps_Handler,
 		},
+		{
+			MethodName: "LabelTransaction",
+			Handler:    _WalletKit_LabelTransaction_Handler,
+		},
 	},
 	Streams:  []grpc.StreamDesc{},
 	Metadata: "walletrpc/walletkit.proto",

lnrpc/walletrpc/walletkit.proto

@@ -97,6 +97,15 @@ service WalletKit {
     broadcast, not confirmation.
     */
     rpc ListSweeps (ListSweepsRequest) returns (ListSweepsResponse);
+
+    /*
+    LabelTransaction adds a label to a transaction. If the transaction already
+    has a label the call will fail unless the overwrite bool is set. This will
+    overwrite the exiting transaction label. Labels must not be empty, and
+    cannot exceed 500 characters.
+    */
+    rpc LabelTransaction (LabelTransactionRequest)
+        returns (LabelTransactionResponse);
 }
 
 message KeyReq {
@@ -367,3 +376,17 @@ message ListSweepsResponse {
         TransactionIDs transaction_ids = 2;
     }
 }
+
+message LabelTransactionRequest {
+    // The txid of the transaction to label.
+    bytes txid = 1;
+
+    // The label to add to the transaction, limited to 500 characters.
+    string label = 2;
+
+    // Whether to overwrite the existing label, if it is present.
+    bool overwrite = 3;
+}
+
+message LabelTransactionResponse {
+}

lnrpc/walletrpc/walletkit.swagger.json

@@ -178,6 +178,9 @@
         }
       }
     },
+    "walletrpcLabelTransactionResponse": {
+      "type": "object"
+    },
     "walletrpcListSweepsResponse": {
       "type": "object",
       "properties": {

lnrpc/walletrpc/walletkit_server.go

@@ -94,6 +94,10 @@ var (
 			Entity: "onchain",
 			Action: "read",
 		}},
+		"/walletrpc.WalletKit/LabelTransaction": {{
+			Entity: "onchain",
+			Action: "write",
+		}},
 	}
 
 	// DefaultWalletKitMacFilename is the default name of the wallet kit
@@ -102,6 +106,10 @@ var (
 	DefaultWalletKitMacFilename = "walletkit.macaroon"
 )
 
+// ErrZeroLabel is returned when an attempt is made to label a transaction with
+// an empty label.
+var ErrZeroLabel = errors.New("cannot label transaction with empty label")
+
 // WalletKit is a sub-RPC server that exposes a tool kit which allows clients
 // to execute common wallet operations. This includes requesting new addresses,
 // keys (for contracts!), and publishing transactions.
@@ -635,3 +643,28 @@ func (w *WalletKit) ListSweeps(ctx context.Context,
 		},
 	}, nil
 }
+
+// LabelTransaction adds a label to a transaction.
+func (w *WalletKit) LabelTransaction(ctx context.Context,
+	req *LabelTransactionRequest) (*LabelTransactionResponse, error) {
+
+	// Check that the label provided in non-zero.
+	if len(req.Label) == 0 {
+		return nil, ErrZeroLabel
+	}
+
+	// Validate the length of the non-zero label. We do not need to use the
+	// label returned here, because the original is non-zero so will not
+	// be replaced.
+	if _, err := labels.ValidateAPI(req.Label); err != nil {
+		return nil, err
+	}
+
+	hash, err := chainhash.NewHash(req.Txid)
+	if err != nil {
+		return nil, err
+	}
+
+	err = w.cfg.Wallet.LabelTransaction(*hash, req.Label, req.Overwrite)
+	return &LabelTransactionResponse{}, err
+}

lntest/itest/lnd_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/btcsuite/btcd/rpcclient"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
+	"github.com/btcsuite/btcwallet/wallet"
 	"github.com/davecgh/go-spew/spew"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd"
@@ -12652,24 +12653,66 @@ func testSweepAllCoins(net *lntest.NetworkHarness, t *harnessTest) {
 		t.Fatalf("expected 2 inputs instead have %v", len(sweepTx.TxIn))
 	}
 
-	// List all transactions relevant to our wallet, and find the sweep tx
+	sweepTxStr := sweepTx.TxHash().String()
-	// so that we can check the correct label has been set.
+	assertTxLabel(ctxb, t, ainz, sweepTxStr, sendCoinsLabel)
-	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+
-	txResp, err := ainz.GetTransactions(ctxt, &lnrpc.GetTransactionsRequest{})
+	// While we are looking at labels, we test our label transaction command
-	if err != nil {
+	// to make sure it is behaving as expected. First, we try to label our
-		t.Fatalf("could not get transactions: %v", err)
+	// transaction with an empty label, and check that we fail as expected.
+	sweepHash := sweepTx.TxHash()
+	_, err = ainz.WalletKitClient.LabelTransaction(
+		ctxt, &walletrpc.LabelTransactionRequest{
+			Txid:      sweepHash[:],
+			Label:     "",
+			Overwrite: false,
+		},
+	)
+	if err == nil {
+		t.Fatalf("expected error for zero transaction label")
 	}
 
-	sweepTxStr := sweepTx.TxHash().String()
+	// Our error will be wrapped in a rpc error, so we check that it
-	for _, txn := range txResp.Transactions {
+	// contains the error we expect.
-		if txn.TxHash == sweepTxStr {
+	if !strings.Contains(err.Error(), walletrpc.ErrZeroLabel.Error()) {
-			if txn.Label != sendCoinsLabel {
+		t.Fatalf("expected: zero label error, got: %v", err)
-				t.Fatalf("expected label: %v, got: %v",
-					sendCoinsLabel, txn.Label)
-			}
-		}
 	}
 
+	// Next, we try to relabel our transaction without setting the overwrite
+	// boolean. We expect this to fail, because the wallet requires setting
+	// of this param to prevent accidental overwrite of labels.
+	_, err = ainz.WalletKitClient.LabelTransaction(
+		ctxt, &walletrpc.LabelTransactionRequest{
+			Txid:      sweepHash[:],
+			Label:     "label that will not work",
+			Overwrite: false,
+		},
+	)
+	if err == nil {
+		t.Fatalf("expected error for tx already labelled")
+	}
+
+	// Our error will be wrapped in a rpc error, so we check that it
+	// contains the error we expect.
+	if !strings.Contains(err.Error(), wallet.ErrTxLabelExists.Error()) {
+		t.Fatalf("expected: label exists, got: %v", err)
+	}
+
+	// Finally, we overwrite our label with a new label, which should not
+	// fail.
+	newLabel := "new sweep tx label"
+	_, err = ainz.WalletKitClient.LabelTransaction(
+		ctxt, &walletrpc.LabelTransactionRequest{
+			Txid:      sweepHash[:],
+			Label:     newLabel,
+			Overwrite: true,
+		},
+	)
+	if err != nil {
+		t.Fatalf("could not label tx: %v", err)
+	}
+
+	assertTxLabel(ctxb, t, ainz, sweepTxStr, newLabel)
+
 	// Finally, Ainz should now have no coins at all within his wallet.
 	balReq := &lnrpc.WalletBalanceRequest{}
 	resp, err := ainz.WalletBalance(ctxt, balReq)
@@ -12695,6 +12738,35 @@ func testSweepAllCoins(net *lntest.NetworkHarness, t *harnessTest) {
 	}
 }
 
+// assertTxLabel is a helper function which finds a target tx in our set
+// of transactions and checks that it has the desired label.
+func assertTxLabel(ctx context.Context, t *harnessTest,
+	node *lntest.HarnessNode, targetTx, label string) {
+
+	// List all transactions relevant to our wallet, and find the tx so that
+	// we can check the correct label has been set.
+	ctxt, cancel := context.WithTimeout(ctx, defaultTimeout)
+	defer cancel()
+
+	txResp, err := node.GetTransactions(
+		ctxt, &lnrpc.GetTransactionsRequest{},
+	)
+	if err != nil {
+		t.Fatalf("could not get transactions: %v", err)
+	}
+
+	// Find our transaction in the set of transactions returned and check
+	// its label.
+	for _, txn := range txResp.Transactions {
+		if txn.TxHash == targetTx {
+			if txn.Label != label {
+				t.Fatalf("expected label: %v, got: %v",
+					label, txn.Label)
+			}
+		}
+	}
+}
+
 // testChannelBackupUpdates tests that both the streaming channel update RPC,
 // and the on-disk channels.backup are updated each time a channel is
 // opened/closed.

lntest/itest/log_error_whitelist.txt

@@ -179,3 +179,5 @@
 <time> [ERR] UTXN: error while graduating class at height=<height>: TxNotifier is exiting
 <time> [ERR] UTXN: Failed to sweep first-stage HTLC (CLTV-delayed) output <chan_point>
 <time> [ERR] UTXN: Notification chan closed, can't advance output <chan_point>
+<time> [ERR] RPCS: [/walletrpc.WalletKit/LabelTransaction]: cannot label transaction with empty label
+<time> [ERR] RPCS: [/walletrpc.WalletKit/LabelTransaction]: transaction already labelled

lnwallet/btcwallet/btcwallet.go

@@ -461,6 +461,17 @@ func (b *BtcWallet) PublishTransaction(tx *wire.MsgTx, label string) error {
 	return nil
 }
 
+// LabelTransaction adds a label to a transaction. If the tx already
+// has a label, this call will fail unless the overwrite parameter
+// is set. Labels must not be empty, and they are limited to 500 chars.
+//
+// Note: it is part of the WalletController interface.
+func (b *BtcWallet) LabelTransaction(hash chainhash.Hash, label string,
+	overwrite bool) error {
+
+	return b.wallet.LabelTransaction(hash, label, overwrite)
+}
+
 // extractBalanceDelta extracts the net balance delta from the PoV of the
 // wallet given a TransactionSummary.
 func extractBalanceDelta(

lnwallet/interface.go

@@ -231,6 +231,11 @@ type WalletController interface {
 	// published transaction.
 	PublishTransaction(tx *wire.MsgTx, label string) error
 
+	// LabelTransaction adds a label to a transaction. If the tx already
+	// has a label, this call will fail unless the overwrite parameter
+	// is set. Labels must not be empty, and they are limited to 500 chars.
+	LabelTransaction(hash chainhash.Hash, label string, overwrite bool) error
+
 	// SubscribeTransactions returns a TransactionSubscription client which
 	// is capable of receiving async notifications as new transactions
 	// related to the wallet are seen within the network, or found in

mock.go

@@ -326,6 +326,13 @@ func (m *mockWalletController) PublishTransaction(tx *wire.MsgTx, _ string) erro
 	m.publishedTransactions <- tx
 	return nil
 }
+
+func (m *mockWalletController) LabelTransaction(_ chainhash.Hash, _ string,
+	_ bool) error {
+
+	return nil
+}
+
 func (*mockWalletController) SubscribeTransactions() (lnwallet.TransactionSubscription, error) {
 	return nil, nil
 }