How to decode smart contract transation

boredape.json

[{"inputs":[{"internalType":"string","name":"name","type":"string"},{"internalType":"string","name":"symbol","type":"string"},{"internalType":"uint256","name":"maxNftSupply","type":"uint256"},{"internalType":"uint256","name":"saleStart","type":"uint256"}],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"approved","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"operator","type":"address"},{"indexed":false,"internalType":"bool","name":"approved","type":"bool"}],"name":"ApprovalForAll","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"from","type":"address"},{"indexed":true,"internalType":"address","name":"to","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Transfer","type":"event"},{"inputs":[],"name":"BAYC_PROVENANCE","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"MAX_APES","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"REVEAL_TIMESTAMP","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"apePrice","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"approve","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"baseURI","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"emergencySetStartingIndexBlock","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"flipSaleState","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"getApproved","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"address","name":"operator","type":"address"}],"name":"isApprovedForAll","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"maxApePurchase","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"numberOfTokens","type":"uint256"}],"name":"mintApe","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"ownerOf","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"reserveApes","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"saleIsActive","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"operator","type":"address"},{"internalType":"bool","name":"approved","type":"bool"}],"name":"setApprovalForAll","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"string","name":"baseURI","type":"string"}],"name":"setBaseURI","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"string","name":"provenanceHash","type":"string"}],"name":"setProvenanceHash","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"revealTimeStamp","type":"uint256"}],"name":"setRevealTimestamp","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"setStartingIndex","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"startingIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"startingIndexBlock","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes4","name":"interfaceId","type":"bytes4"}],"name":"supportsInterface","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenOfOwnerByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"tokenURI","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"transferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}]p

decode_smart_contract_transation.go

package main

import (
	"context"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"os"
	"strings"

	"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"
)

func MapToJson(param map[string]interface{}) string {
	dataType, _ := json.Marshal(param)
	dataString := string(dataType)
	return dataString
}

const PROVIDER_URL = "https://ethereum.publicnode.com"

func GetLocalABI(path string) string {
	// read abi json from local file
	abiFile, err := os.Open(path)
	if err != nil {
		log.Fatal(err)
	}
	defer abiFile.Close()

	result, err := io.ReadAll(abiFile)
	if err != nil {
		log.Fatal(err)
	}
	return string(result)
}

// refer
// https://github.com/ethereum/web3.py/blob/master/web3/contract.py#L435
func DecodeTransactionInputData(contractABI *abi.ABI, data []byte) {
	// The first 4 bytes of the txn represent the ID of the method in the ABI
	methodSigData := data[:4]
	method, err := contractABI.MethodById(methodSigData)
	if err != nil {
		log.Fatal(err)
	}

	// parse the inputs to this method
	inputsSigData := data[4:]
	inputsMap := make(map[string]interface{})
	if err := method.Inputs.UnpackIntoMap(inputsMap, inputsSigData); err != nil {
		log.Fatal(err)
	}
	fmt.Printf("Method Name: %s\n", method.Name)
	fmt.Printf("Method inputs: %v\n", MapToJson(inputsMap))
}

func GetTransactionMessage(tx *types.Transaction) types.Message {
	msg, err := tx.AsMessage(types.LatestSignerForChainID(tx.ChainId()), nil)
	if err != nil {
		log.Fatal(err)
	}
	return msg
}

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", GetTransactionMessage(tx).From().Hex()) // from field is not inside of transation
	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()))
	fmt.Print("\n")

}

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)
		}
		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:] {
				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{})
			err = contractABI.UnpackIntoMap(outputDataMap, event.Name, vLog.Data)
			if err != nil {
				log.Fatal(err)
			}
			fmt.Printf("Event outputs: %v\n", outputDataMap)
		}
	}
}

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() {
	// read parameter from the command line
	txHashStr := os.Args[1]

	// client wrappers for the Ethereum RPC API.
	client, err := ethclient.Dial(PROVIDER_URL)
	if err != nil {
		log.Println(err)
		continue
	}

	// TransactionByHash returns the transaction with the given hash.
	txHash := common.HexToHash(txHashStr)
	tx, isPending, err := client.TransactionByHash(context.Background(), txHash)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("tx isPending: %t\n", isPending)

	// parse the transaction information
	fmt.Println("\nStart to pase transation base info")
	ParseTransactionBaseInfo(tx)

	// get abi from local
	contractABI, err := abi.JSON(strings.NewReader(GetLocalABI("boredape.json")))
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println("\nStart to decode transation input data")
	DecodeTransactionInputData(&contractABI, tx.Data())

	fmt.Println("\nStart to decode transation log")
	receipt := GetTransactionReceipt(client, txHash)
	DecodeTransactionLogs(receipt, &contractABI)

}