Description

Simulates a list of transactions in sequence and returns a list of decoded traces and logs that occurred for each transaction during simulation.

Note that this method does not run any transactions on the blockchain.

Parameters

transactions object parameters

Response

SimulateExecutionResponse object parameters

calls array property parameters

logs array property parameters

Example Request and Response

Prerequisite: You will need to install the Alchemy SDK before making requests with it.

The commands for installing it using npm or yarn are given below:

$
npm install alchemy-sdk

Request

1
// Imports the Alchemy SDK
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const { Alchemy, Network } = require("alchemy-sdk");
3
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// Configures the Alchemy SDK
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const config = {
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    apiKey: "alchemy-replit", // Replace with your API key
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    network: Network.ETH_MAINNET, // Replace with your network
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};
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// Creates an Alchemy object instance with the config to use for making requests
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const alchemy = new Alchemy(config);
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const main = async () => {
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    // define the transaction hash
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    const trnxs = [
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      {
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      transaction:
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"0x88df016429689c079f3b2f6ad39fa052532c56795b733da78a91ebe6a713944b"}
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    ];
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    //Call the method to display the transaction simulation execution
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    const response = await alchemy.transact.simulateExecutionBundle(trnxs)
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    //Logging the response to the console
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    console.log(response)
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}
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main();

Response

$
{
>
  calls: [
>
    {
>
      type: 'CALL',
>
      from: '0xa7d9ddbe1f17865597fbd27ec712455208b6b76d',
>
      to: '0xf02c1c8e6114b1dbe8937a39260b5b0a374432bb',
>
      value: '0xf3dbb76162000',
>
      gas: '0x6fb0',
>
      gasUsed: '0x53a0',
>
      input: '0x68656c6c6f21',
>
      output: '0x'
>
    }
>
  ],
>
  logs: []
>
}

Use Cases

Here are some potential use cases for the simulateExecutionBundle method:

• Testing: You can use simulateExecutionBundle to test the logic of your smart contract without incurring the cost of actually executing the transactions on the blockchain.

• Gas estimation: The method can also be used to estimate the amount of gas required to execute a series of transactions. This can be useful in determining the appropriate gas limit to set for a transaction to ensure it is processed efficiently.

• Debugging: When you encounter errors while interacting with a smart contract, simulateExecutionBundle can help you debug the issue. By simulating the execution of the set of transactions, you can identify the specific line of code that is causing the error.

Related Methods

Here are the methods related to simulateExecutionBundle:

• simulateExecution: Simulates a single transaction and the results and returns a list of decoded traces and logs that occurred during the transaction simulation.