novice-stack · October 25, 2022 06:37 · Jun 2, 2022 · Jun 1, 2022 · Jun 1, 2022 · Jun 1, 2022
diff --git a/parseTransaction.go b/parseTransaction.go
@@ -104,11 +104,9 @@ func DecodeTransactionLogs(receipt *types.Receipt, contractABI *abi.ABI) {
 		if len(vLog.Data) > 0 {
 			fmt.Printf("Log Data in Hex: %s\n", hex.EncodeToString(vLog.Data))
 			outputDataMap := make(map[string]interface{})
-			if len(vLog.Data) != 0 {
-				err = contractABI.UnpackIntoMap(outputDataMap, event.Name, vLog.Data)
-				if err != nil {
-					log.Fatal(err)
-				}
+			err = contractABI.UnpackIntoMap(outputDataMap, event.Name, vLog.Data)
+			if err != nil {
+				log.Fatal(err)
 			}
 			fmt.Printf("Event outputs: %v\n", outputDataMap)
 		}

diff --git a/parseTransaction.go b/parseTransaction.go
@@ -93,7 +93,7 @@ func DecodeTransactionLogs(receipt *types.Receipt, contractABI *abi.ABI) {
 		if err != nil {
 			log.Fatal(err)
 		}
-		log.Printf("Event Name: %s\n", event.Name)
+		fmt.Printf("Event Name: %s\n", event.Name)
 		// topic[1:] is other indexed params in event
 		if len(vLog.Topics) > 1 {
 			for i, param := range vLog.Topics[1:] {

diff --git a/parseTransaction.go b/parseTransaction.go
@@ -38,10 +38,10 @@ func GetContractRawABI(address string, apiKey string) (*RawABIResponse, error) {
 		return nil, err
 	}
 	if !resp.IsSuccess() {
-		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s", resp))
+		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s\n", resp))
 	}
 	if *rawABIResponse.Status != "1" {
-		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s", *rawABIResponse.Result))
+		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s\n", *rawABIResponse.Result))
 	}
 
 	return rawABIResponse, nil
@@ -93,7 +93,7 @@ func DecodeTransactionLogs(receipt *types.Receipt, contractABI *abi.ABI) {
 		if err != nil {
 			log.Fatal(err)
 		}
-		log.Printf("Event Name %s\n", event.Name)
+		log.Printf("Event Name: %s\n", event.Name)
 		// topic[1:] is other indexed params in event
 		if len(vLog.Topics) > 1 {
 			for i, param := range vLog.Topics[1:] {

diff --git a/parseTransaction.go b/parseTransaction.go
@@ -66,19 +66,19 @@ func DecodeTransactionInputData(contractABI *abi.ABI, data []byte) {
 	fmt.Printf("Method inputs: %v\n", inputsMap)
 }
 
-func getTransactionFrom(tx *types.Transaction) common.Address {
+func GetTransactionMessage(tx *types.Transaction) types.Message {
 	msg, err := tx.AsMessage(types.LatestSignerForChainID(tx.ChainId()), nil)
 	if err != nil {
 		log.Fatal(err)
 	}
-	return msg.From()
+	return msg
 }
 
-func GetTransactionBaseInfo(tx *types.Transaction) {
+func ParseTransactionBaseInfo(tx *types.Transaction) {
 	fmt.Printf("Hash: %s\n", tx.Hash().Hex())
 	fmt.Printf("ChainId: %d\n", tx.ChainId())
 	fmt.Printf("Value: %s\n", tx.Value().String())
-	fmt.Printf("From: %s\n", getTransactionFrom(tx).Hex())
+	fmt.Printf("From: %s\n", GetTransactionMessage(tx).From().Hex())
 	fmt.Printf("To: %s\n", tx.To().Hex())
 	fmt.Printf("Gas: %d\n", tx.Gas())
 	fmt.Printf("Gas Price: %d\n", tx.GasPrice().Uint64())
@@ -140,7 +140,7 @@ func main() {
 	// get etherscanAPIKEY from https://docs.etherscan.io/getting-started/viewing-api-usage-statistics
 	const etherscanAPIKEY = "M3SF4WTDC4NWQIIVNAZDFXBW1SW49QWDNZ"
 	const providerUrl = "https://ropsten.infura.io/v3/28d5693e8bee4b58a61f0c627d62331e"
-	
+
 	client, err := ethclient.Dial(providerUrl)
 	if err != nil {
 		log.Fatal(err)
@@ -152,7 +152,7 @@ func main() {
 		log.Fatal(err)
 	}
 	fmt.Printf("tx isPending: %t\n", isPending)
-	GetTransactionBaseInfo(tx)
+	ParseTransactionBaseInfo(tx)
 	contractABI := GetContractABI(tx.To().String(), etherscanAPIKEY)
 	DecodeTransactionInputData(contractABI, tx.Data())
 	receipt := GetTransactionReceipt(client, txHash)

diff --git a/parseTransaction.go b/parseTransaction.go
@@ -0,0 +1,160 @@
+package main
+
+import (
+	"context"
+	"encoding/hex"
+	"fmt"
+	"github.com/ethereum/go-ethereum/accounts/abi"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethclient"
+	"github.com/go-resty/resty/v2"
+	"log"
+	"strings"
+)
+
+type (
+	RawABIResponse struct {
+		Status  *string `json:"status"`
+		Message *string `json:"message"`
+		Result  *string `json:"result"`
+	}
+)
+
+func GetContractRawABI(address string, apiKey string) (*RawABIResponse, error) {
+	client := resty.New()
+	rawABIResponse := &RawABIResponse{}
+	resp, err := client.R().
+		SetQueryParams(map[string]string{
+			"module":  "contract",
+			"action":  "getabi",
+			"address": address,
+			"apikey":  apiKey,
+		}).
+		SetResult(rawABIResponse).
+		Get("https://api-ropsten.etherscan.io/api")
+
+	if err != nil {
+		return nil, err
+	}
+	if !resp.IsSuccess() {
+		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s", resp))
+	}
+	if *rawABIResponse.Status != "1" {
+		return nil, fmt.Errorf(fmt.Sprintf("Get contract raw abi failed: %s", *rawABIResponse.Result))
+	}
+
+	return rawABIResponse, nil
+}
+
+// refer
+// https://github.com/ethereum/web3.py/blob/master/web3/contract.py#L435
+func DecodeTransactionInputData(contractABI *abi.ABI, data []byte) {
+	methodSigData := data[:4]
+	inputsSigData := data[4:]
+	method, err := contractABI.MethodById(methodSigData)
+	if err != nil {
+		log.Fatal(err)
+	}
+	inputsMap := make(map[string]interface{})
+	if err := method.Inputs.UnpackIntoMap(inputsMap, inputsSigData); err != nil {
+		log.Fatal(err)
+	} else {
+		fmt.Println(inputsMap)
+	}
+	fmt.Printf("Method Name: %s\n", method.Name)
+	fmt.Printf("Method inputs: %v\n", inputsMap)
+}
+
+func getTransactionFrom(tx *types.Transaction) common.Address {
+	msg, err := tx.AsMessage(types.LatestSignerForChainID(tx.ChainId()), nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return msg.From()
+}
+
+func GetTransactionBaseInfo(tx *types.Transaction) {
+	fmt.Printf("Hash: %s\n", tx.Hash().Hex())
+	fmt.Printf("ChainId: %d\n", tx.ChainId())
+	fmt.Printf("Value: %s\n", tx.Value().String())
+	fmt.Printf("From: %s\n", getTransactionFrom(tx).Hex())
+	fmt.Printf("To: %s\n", tx.To().Hex())
+	fmt.Printf("Gas: %d\n", tx.Gas())
+	fmt.Printf("Gas Price: %d\n", tx.GasPrice().Uint64())
+	fmt.Printf("Nonce: %d\n", tx.Nonce())
+	fmt.Printf("Transaction Data in hex: %s\n", hex.EncodeToString(tx.Data()))
+}
+
+func DecodeTransactionLogs(receipt *types.Receipt, contractABI *abi.ABI) {
+	for _, vLog := range receipt.Logs {
+		// topic[0] is the event name
+		event, err := contractABI.EventByID(vLog.Topics[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+		log.Printf("Event Name %s\n", event.Name)
+		// topic[1:] is other indexed params in event
+		if len(vLog.Topics) > 1 {
+			for i, param := range vLog.Topics[1:] {
+				fmt.Printf("Indexed params %d in hex: %s\n", i, param)
+				fmt.Printf("Indexed params %d decoded %s\n", i, common.HexToAddress(param.Hex()))
+			}
+		}
+		if len(vLog.Data) > 0 {
+			fmt.Printf("Log Data in Hex: %s\n", hex.EncodeToString(vLog.Data))
+			outputDataMap := make(map[string]interface{})
+			if len(vLog.Data) != 0 {
+				err = contractABI.UnpackIntoMap(outputDataMap, event.Name, vLog.Data)
+				if err != nil {
+					log.Fatal(err)
+				}
+			}
+			fmt.Printf("Event outputs: %v\n", outputDataMap)
+		}
+	}
+}
+
+func GetContractABI(contractAddress, etherscanAPIKey string) *abi.ABI {
+	rawABIResponse, err := GetContractRawABI(contractAddress, etherscanAPIKey)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	contractABI, err := abi.JSON(strings.NewReader(*rawABIResponse.Result))
+	if err != nil {
+		log.Fatal(err)
+	}
+	return &contractABI
+}
+
+func GetTransactionReceipt(client *ethclient.Client, txHash common.Hash) *types.Receipt {
+	receipt, err := client.TransactionReceipt(context.Background(), txHash)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return receipt
+}
+
+func main() {
+	// get etherscanAPIKEY from https://docs.etherscan.io/getting-started/viewing-api-usage-statistics
+	const etherscanAPIKEY = "M3SF4WTDC4NWQIIVNAZDFXBW1SW49QWDNZ"
+	const providerUrl = "https://ropsten.infura.io/v3/28d5693e8bee4b58a61f0c627d62331e"
+
+	client, err := ethclient.Dial(providerUrl)
+	if err != nil {
+		log.Fatal(err)
+	}
+	// https://ropsten.etherscan.io/tx/0x7e605f68ff30509eb2bf3238936ef65a01bfa25243488c007244aabe645d0ec9
+	txHash := common.HexToHash("0x7e605f68ff30509eb2bf3238936ef65a01bfa25243488c007244aabe645d0ec9")
+	tx, isPending, err := client.TransactionByHash(context.Background(), txHash)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("tx isPending: %t\n", isPending)
+	GetTransactionBaseInfo(tx)
+	contractABI := GetContractABI(tx.To().String(), etherscanAPIKEY)
+	DecodeTransactionInputData(contractABI, tx.Data())
+	receipt := GetTransactionReceipt(client, txHash)
+	DecodeTransactionLogs(receipt, contractABI)
+}