[AA] Use bundler estimations, implement custom gas pricing (#140)

Author: 0xFirekeeper

Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/BundlerClient.cs

@@ -41,7 +41,7 @@ public static async Task<PMSponsorOperationResponse> PMSponsorUserOperation(stri
         private static async Task<RpcResponseMessage> BundlerRequest(string url, string apiKey, object requestId, string method, params object[] args)
         {
             using HttpClient client = new HttpClient();
-            ThirdwebDebug.Log($"Bundler Request: {method}({string.Join(", ", args)})");
+            ThirdwebDebug.Log($"Bundler Request: {method}({JsonConvert.SerializeObject(args)}");
             var requestMessage = new RpcRequestMessage(requestId, method, args);
             string requestMessageJson = JsonConvert.SerializeObject(requestMessage);
 

Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/Constants.cs

@@ -3,7 +3,7 @@ namespace Thirdweb.AccountAbstraction
     public static class Constants
     {
         public const string DEFAULT_ENTRYPOINT_ADDRESS = "0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789"; // v0.6
-        public const int DUMMY_SIG_LENGTH = 65;
+        public const string DUMMY_SIG = "0xfffffffffffffffffffffffffffffff0000000000000000000000000000000007aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa1c";
         public const string DUMMY_PAYMASTER_AND_DATA_HEX =
             "0x0101010101010101010101010101010101010101000000000000000000000000000000000000000000000000000001010101010100000000000000000000000000000000000000000000000000000000000000000101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101";
     }

Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/SmartWallet.cs

@@ -189,10 +189,7 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
 
             var paramList = JsonConvert.DeserializeObject<List<object>>(JsonConvert.SerializeObject(requestMessage.RawParameters));
             var transactionInput = JsonConvert.DeserializeObject<TransactionInput>(JsonConvert.SerializeObject(paramList[0]));
-            var latestBlock = await Blocks.GetBlock(await Blocks.GetLatestBlockNumber());
-            var dummySig = new byte[Constants.DUMMY_SIG_LENGTH];
-            for (int i = 0; i < Constants.DUMMY_SIG_LENGTH; i++)
-                dummySig[i] = 0x01;
+            var dummySig = Constants.DUMMY_SIG;
 
             var (initCode, gas) = await GetInitCode();
 
@@ -207,37 +204,47 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
 
             // Create the user operation and its safe (hexified) version
 
+            var gasPrices = await Utils.GetGasPriceAsync(ThirdwebManager.Instance.SDK.session.ChainId);
+
             var partialUserOp = new EntryPointContract.UserOperation()
             {
                 Sender = Accounts[0],
                 Nonce = await GetNonce(),
                 InitCode = initCode,
                 CallData = executeInput.Data.HexStringToByteArray(),
-                CallGasLimit = 50000 + (transactionInput.Gas != null ? (transactionInput.Gas.Value < 21000 ? 100000 : transactionInput.Gas.Value) : 100000),
-                VerificationGasLimit = 100000 + gas,
-                PreVerificationGas = 21000,
-                MaxFeePerGas = latestBlock.BaseFeePerGas.Value * 2 + BigInteger.Parse("1500000000"),
-                MaxPriorityFeePerGas = BigInteger.Parse("1500000000"),
-                PaymasterAndData = Constants.DUMMY_PAYMASTER_AND_DATA_HEX.HexStringToByteArray(),
-                Signature = dummySig,
+                CallGasLimit = 0,
+                VerificationGasLimit = 0,
+                PreVerificationGas = 0,
+                MaxFeePerGas = gasPrices.MaxFeePerGas,
+                MaxPriorityFeePerGas = gasPrices.MaxPriorityFeePerGas,
+                PaymasterAndData = new byte[] { },
+                Signature = dummySig.HexStringToByteArray(),
             };
-            partialUserOp.PreVerificationGas = partialUserOp.CalcPreVerificationGas();
-            var partialUserOpHexified = partialUserOp.EncodeUserOperation();
 
             // Update paymaster data if any
 
-            partialUserOp.PaymasterAndData = await GetPaymasterAndData(requestMessage.Id, partialUserOpHexified, apiKey);
+            partialUserOp.PaymasterAndData = await GetPaymasterAndData(requestMessage.Id, partialUserOp.EncodeUserOperation(), apiKey);
+
+            // Estimate gas
+
+            var gasEstimates = await BundlerClient.EthEstimateUserOperationGas(Config.bundlerUrl, apiKey, requestMessage.Id, partialUserOp.EncodeUserOperation(), Config.entryPointAddress);
+            partialUserOp.CallGasLimit = 50000 + new HexBigInteger(gasEstimates.CallGasLimit).Value;
+            partialUserOp.VerificationGasLimit = new HexBigInteger(gasEstimates.VerificationGas).Value;
+            partialUserOp.PreVerificationGas = new HexBigInteger(gasEstimates.PreVerificationGas).Value;
+
+            // Update paymaster data if any
+
+            partialUserOp.PaymasterAndData = await GetPaymasterAndData(requestMessage.Id, partialUserOp.EncodeUserOperation(), apiKey);
 
             // Hash, sign and encode the user operation
 
             partialUserOp.Signature = await partialUserOp.HashAndSignUserOp(Config.entryPointAddress);
-            partialUserOpHexified = partialUserOp.EncodeUserOperation();
 
             // Send the user operation
 
             ThirdwebDebug.Log("Valid UserOp: " + JsonConvert.SerializeObject(partialUserOp));
-            ThirdwebDebug.Log("Valid Encoded UserOp: " + JsonConvert.SerializeObject(partialUserOpHexified));
-            var userOpHash = await BundlerClient.EthSendUserOperation(Config.bundlerUrl, apiKey, requestMessage.Id, partialUserOpHexified, Config.entryPointAddress);
+            ThirdwebDebug.Log("Valid Encoded UserOp: " + JsonConvert.SerializeObject(partialUserOp.EncodeUserOperation()));
+            var userOpHash = await BundlerClient.EthSendUserOperation(Config.bundlerUrl, apiKey, requestMessage.Id, partialUserOp.EncodeUserOperation(), Config.entryPointAddress);
             ThirdwebDebug.Log("UserOp Hash: " + userOpHash);
 
             // Wait for the transaction to be mined

Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/UserOpUtils.cs

@@ -64,75 +64,5 @@ public static UserOperationHexified EncodeUserOperation(this EntryPointContract.
                 signature = userOperation.Signature.ByteArrayToHexString()
             };
         }
-
-        public static int CalcPreVerificationGas(this EntryPointContract.UserOperation userOp, GasOverheads gasOverheads = null)
-        {
-            GasOverheads ov = gasOverheads ?? new GasOverheads();
-
-            userOp.Signature = new byte[ov.sigSize];
-            userOp.PreVerificationGas = 21000;
-
-            byte[] packed = userOp.PackUserOp(false);
-            int lengthInWord = (packed.Length + 31) / 32;
-
-            int callDataCost = 0;
-            foreach (byte b in packed)
-            {
-                callDataCost += (b == 0) ? ov.zeroByte : ov.nonZeroByte;
-            }
-
-            int totalGas = callDataCost + ov.fixedGas / ov.bundleSize + ov.perUserOp + ov.perUserOpWord * lengthInWord;
-
-            return totalGas;
-        }
-
-        public static byte[] PackUserOp(this EntryPointContract.UserOperation op, bool forSignature = true)
-        {
-            var abiEncode = new Nethereum.ABI.ABIEncode();
-            var sha3Keccak = new Nethereum.Util.Sha3Keccack();
-
-            if (forSignature)
-            {
-                return abiEncode.GetABIEncoded(
-                    op.Sender,
-                    op.Nonce,
-                    sha3Keccak.CalculateHash(op.InitCode),
-                    sha3Keccak.CalculateHash(op.CallData),
-                    op.CallGasLimit,
-                    op.VerificationGasLimit,
-                    op.PreVerificationGas,
-                    op.MaxFeePerGas,
-                    op.MaxPriorityFeePerGas,
-                    sha3Keccak.CalculateHash(op.PaymasterAndData)
-                );
-            }
-            else
-            {
-                return abiEncode.GetABIEncodedPacked(
-                    op.Sender,
-                    op.Nonce,
-                    op.InitCode,
-                    op.CallData,
-                    op.CallGasLimit,
-                    op.VerificationGasLimit,
-                    op.PreVerificationGas,
-                    op.MaxFeePerGas,
-                    op.MaxPriorityFeePerGas,
-                    op.PaymasterAndData,
-                    op.Signature
-                );
-            }
-        }
-    }
-
-    public class GasOverheads
-    {
-        public int fixedGas = 21000;
-        public int perUserOp = 18300;
-        public int perUserOpWord = 4;
-        public int zeroByte = 4;
-        public int nonZeroByte = 16;
-        public int bundleSize = 1;
-        public int sigSize = Constants.DUMMY_SIG_LENGTH;
     }
 }

Assets/Thirdweb/Core/Scripts/ThirdwebSession.cs

@@ -63,17 +63,24 @@ internal async Task<string> Connect(WalletConnection walletConnection)
                     ActiveWallet = new ThirdwebMetamask();
                     break;
                 case WalletProvider.SmartWallet:
-                    await Connect(
-                        new WalletConnection(
-                            provider: walletConnection.personalWallet,
-                            chainId: walletConnection.chainId,
-                            password: walletConnection.password,
-                            email: walletConnection.email,
-                            authOptions: walletConnection.authOptions
-                        )
-                    );
                     if (Options.smartWalletConfig == null)
                         throw new UnityException("Smart wallet config is required for smart wallet connection method!");
+                    if (ActiveWallet?.GetProvider() != walletConnection.personalWallet)
+                    {
+                        await Connect(
+                            new WalletConnection(
+                                provider: walletConnection.personalWallet,
+                                chainId: walletConnection.chainId,
+                                password: walletConnection.password,
+                                email: walletConnection.email,
+                                authOptions: walletConnection.authOptions
+                            )
+                        );
+                    }
+                    else
+                    {
+                        ThirdwebDebug.Log("Already connected to personal wallet, skipping connection.");
+                    }
                     ActiveWallet = new ThirdwebSmartWallet(ActiveWallet, Options.smartWalletConfig.Value);
                     break;
                 case WalletProvider.Hyperplay:

Assets/Thirdweb/Core/Scripts/Types.cs

@@ -561,4 +561,35 @@ public override readonly string ToString()
                 + $"\n>approvedCallTargets: {approvedCallTargets}";
         }
     }
+
+    [System.Serializable]
+    public class GasPriceParameters
+    {
+        public BigInteger MaxFeePerGas { get; private set; }
+        public BigInteger MaxPriorityFeePerGas { get; private set; }
+
+        public GasPriceParameters(BigInteger maxFeePerGas, BigInteger maxPriorityFeePerGas)
+        {
+            MaxFeePerGas = maxFeePerGas;
+            MaxPriorityFeePerGas = maxPriorityFeePerGas;
+        }
+    }
+
+    [System.Serializable]
+    public class PolygonGasStationResult
+    {
+        public GasStationResult safeLow;
+        public GasStationResult standard;
+        public GasStationResult fast;
+        public BigInteger estimatedBaseFee;
+        public int blockTime;
+        public BigInteger blockNumber;
+    }
+
+    [System.Serializable]
+    public class GasStationResult
+    {
+        public double maxPriorityFee;
+        public double maxFee;
+    }
 }

Assets/Thirdweb/Core/Scripts/Utils.cs

@@ -12,6 +12,8 @@
 using Nethereum.Web3;
 using Newtonsoft.Json.Linq;
 using System.Globalization;
+using System.Linq;
+using System.Net.Http;
 
 namespace Thirdweb
 {
@@ -409,9 +411,9 @@ public static string AppendBundleIdQueryParam(this string uri)
             return uri;
         }
 
-        public static Web3 GetWeb3()
+        public static Web3 GetWeb3(BigInteger? chainId = null)
         {
-            return new Web3(new ThirdwebClient(new Uri(ThirdwebManager.Instance.SDK.session.RPC)));
+            return new Web3(new ThirdwebClient(new Uri(chainId == null ? ThirdwebManager.Instance.SDK.session.RPC : $"https://{chainId}.rpc.thirdweb.com")));
         }
 
         public static string GetNativeTokenWrapper(BigInteger chainId)
@@ -465,5 +467,102 @@ public static string JSDateToUnixTimestamp(string dateString)
             long unixTimestamp = (long)(dateTime - unixEpoch).TotalSeconds;
             return unixTimestamp.ToString();
         }
+
+        public async static Task<GasPriceParameters> GetGasPriceAsync(BigInteger chainId)
+        {
+            if (chainId == 137 || chainId == 80001)
+            {
+                return await GetPolygonGasPriceParameters((int)chainId);
+            }
+
+            var web3 = GetWeb3(chainId);
+            var gasPrice = (await web3.Eth.GasPrice.SendRequestAsync()).Value;
+
+            if (chainId == 42220) // celo mainnet
+            {
+                gasPrice = BigInteger.Multiply(gasPrice, 3) / 2;
+                return new GasPriceParameters(gasPrice, gasPrice);
+            }
+
+            if (
+                chainId == 1 // mainnet
+                || chainId == 11155111 // sepolia
+                || chainId == 42161 // arbitrum
+                || chainId == 421613 // arbitrum goerli
+                || chainId == 534352 // scroll
+                || chainId == 534351 // scroll sepolia
+                || chainId == 5000 // mantle
+                || chainId == 22222 // nautilus
+                || chainId == 8453 // base
+                || chainId == 53935 // dfk
+                || chainId == 44787 // celo alfajores
+                || chainId == 43114 // avalanche
+                || chainId == 43113 // avalanche fuji
+            )
+            {
+                gasPrice = BigInteger.Multiply(gasPrice, 10) / 9;
+                return new GasPriceParameters(gasPrice, gasPrice);
+            }
+
+            var maxPriorityFeePerGas = new BigInteger(2000000000) > gasPrice ? gasPrice : new BigInteger(2000000000);
+
+            var feeHistory = await web3.Eth.FeeHistory.SendRequestAsync(new Nethereum.Hex.HexTypes.HexBigInteger(20), Nethereum.RPC.Eth.DTOs.BlockParameter.CreateLatest(), new double[] { 20 });
+
+            if (feeHistory.Reward == null)
+            {
+                gasPrice = BigInteger.Multiply(gasPrice, 3) / 2;
+                maxPriorityFeePerGas = gasPrice;
+            }
+            else
+            {
+                var feeAverage = feeHistory.Reward.Select(r => r[0]).Aggregate(BigInteger.Zero, (acc, cur) => cur + acc) / 10;
+                if (feeAverage > gasPrice)
+                {
+                    gasPrice = feeAverage;
+                }
+                maxPriorityFeePerGas = gasPrice;
+            }
+
+            return new GasPriceParameters(gasPrice, maxPriorityFeePerGas);
+        }
+
+        public async static Task<GasPriceParameters> GetPolygonGasPriceParameters(int chainId)
+        {
+            using var httpClient = new HttpClient();
+            string gasStationUrl;
+            BigInteger minGasPrice = 1;
+            switch (chainId)
+            {
+                case 137:
+                    gasStationUrl = "https://gasstation.polygon.technology/v2";
+                    minGasPrice = 31;
+                    break;
+                case 80001:
+                    gasStationUrl = "https://gasstation-testnet.polygon.technology/v2";
+                    minGasPrice = 1;
+                    break;
+                default:
+                    throw new UnityException("Unsupported chain id");
+            }
+            try
+            {
+                var response = await httpClient.GetAsync(gasStationUrl);
+                response.EnsureSuccessStatusCode();
+                string responseBody = await response.Content.ReadAsStringAsync();
+                var data = JsonConvert.DeserializeObject<PolygonGasStationResult>(responseBody);
+                return new GasPriceParameters(GweiToWei(data.fast.maxFee), GweiToWei(data.fast.maxPriorityFee));
+            }
+            catch (Exception e)
+            {
+                ThirdwebDebug.LogWarning($"Failed to get gas price from Polygon gas station, using default: {e.Message}");
+            }
+            var gasPrice = await GetWeb3().Eth.GasPrice.SendRequestAsync();
+            return new GasPriceParameters(gasPrice, minGasPrice);
+        }
+
+        public static BigInteger GweiToWei(double gweiAmount)
+        {
+            return new BigInteger(gweiAmount * 1e9);
+        }
     }
 }