The Transaction Simulator is designed to bolster the efficiency and security of blockchain transactions. It offers crucial capabilities such as:

• Simulating native currency transfers.
• Simulating ERC20 token transfers.

By leveraging these simulations, developers can:

1. Estimate Fees Accurately: One of the primary challenges in sending blockchain transactions is determining an optimal gas fee that ensures quick confirmation without overpaying. By simulating a transaction before sending it, developers can get a precise estimate of the gas fee, saving costs and improving user experience.
2. Enhance Safety: Simulating transactions allows developers to anticipate and catch potential errors or vulnerabilities in transaction logic. By identifying these issues in a simulation environment, developers can prevent costly mistakes when deploying actual transactions.
3. Optimize Transaction Parameters: Beyond just estimating fees, simulating transactions can help developers fine-tune other parameters, such as gas limit or nonce, to optimize transaction performance.

It is built upon popular packages like ethers, ensuring a robust, reliable, and secure foundation for all simulation activities.

🚀 Quick Start

1. Installation

   Firstly, ensure that the @tatumio/transaction-simulator package is set as a dependency within your project. Next, import the Transaction Simulator extension:

   JavaScript

   import { TransactionSimulator } from '@tatumio/transaction-simulator';
   

2. Initialization

   Create an instance of Tatum SDK passing TransactionSimulator as one of extensions.

   JavaScript

   const tatumSdk = await TatumSDK.init<Ethereum>({
        network: Network.ETHEREUM,
        configureExtensions: [
            TransactionSimulator,
        ]
    })
   

🛠️ ERC20 Token Transfers:

1. Define Your Token Transfer Payload: To simulate an ERC20 token transfer, you will use the TokenTransfer object.

   JavaScript

   const tokenTransferPayload: TokenTransfer = {
     to: 'recipient_address',
     from: 'sender_address',
     gas: '0xB411', // optional
     gasPrice: '0x4B16C370A', //optional
     value: 500, // example token amount to send
     tokenContractAddress: 'your_erc20_token_contract_address'
   };
   

2. Call simulateTransferErc20: With your TokenTransfer payload ready, pass it to the simulateTransferErc20 method.

   JavaScript

   const tokenSimulationResult = await simulateTransferErc20(tokenTransferPayload);
   

   This method fetches token details, simulates the transaction, and returns an estimation of the transaction's outcome along with the necessary gas fees.

3. Check simulation results:

   JSON

   {
     "transactionDetails": {
       "from": "0xDce92f40cAdDE2C4e3EA78b8892c540e6bFe2f81",
       "to": "0xaf758da9f7bdaa7590175193388e9c99427cc2d2",
       "tokenContractAddress": "0xdac17f958d2ee523a2206206994597c13d831ec7",
       "data": "0xa9059cbb000000000000000000000000af758da9f7bdaa7590175193388e9c99427cc2d2000000000000000000000000000000000000000000000000000000001908b100",
       "gasLimit": 46097,
       "gasPrice": 20156528394
     },
     "status": "success",
     "balanceChanges": {
       "0xDce92f40cAdDE2C4e3EA78b8892c540e6bFe2f81": {
         "from": 243656557299636170000,
         "to": 243655628144146780000
       }
     },
     "tokenTransfers": {
       "0xdac17f958d2ee523a2206206994597c13d831ec7": {
         "name": "TetherUSD",
         "symbol": "USDT",
         "decimals": 6,
         "0xDce92f40cAdDE2C4e3EA78b8892c540e6bFe2f81": {
           "from": 2387468.080258,
           "to": 2387048.080258
         },
         "0xaf758da9f7bdaa7590175193388e9c99427cc2d2": {
           "from": 422.304,
           "to": 842.304
         }
       }
     }
   }
   

By using the above methods, you can efficiently predict the behavior and costs of your transactions before actually broadcasting them, ensuring optimized and error-free transactions.

Gas Price Estimation:

• Methods accept gasPrice as a parameter. If you don't provide it, the gas price will be estimated using the eth_gasPrice method.
• Methods accept gas as a parameter. If you don't provide it, the gas limit will be estimated using the eth_estimateGas method.

Supported Networks

Network.ARBITRUM_ONE,
Network.AVALANCHE_C,
Network.CELO,
Network.CELO_ALFAJORES,
Network.CHILIZ,
Network.ETHEREUM,
Network.ETHEREUM_SEPOLIA,
Network.ETHEREUM_HOLESKY,
Network.ETHEREUM_CLASSIC,
Network.POLYGON,
Network.POLYGON_AMOY,
Network.BINANCE_SMART_CHAIN,
Network.BINANCE_SMART_CHAIN_TESTNET,
Network.OPTIMISM,
Network.OPTIMISM_TESTNET,