Ethereum: Create/set “subId” by createSubscription() and get “subId” vrfCoordinatorV2_5Mock calling by javascript in hardhat environment

I can provide you with an article based on the given specification. Please note that I assume that the createSubscription(), getSubId() functions are already implemented and available in JavaScript code.

Ethereum: Creating and setting subids using VRF coordinators

In this article, we will look at how to create and set subids using VRF (verifiable random function) coordinators in the hardhat environment.

Hardhat Environment Overview

Hardhat is a popular Ethereum development environment that allows us to build and deploy smart contracts on the Ethereum network. It provides an easy-to-use interface for interacting with the Ethereum blockchain, making it ideal for rapid prototyping and development.

Creating and setting subids using VRF coordinators

To create subids using VRF coordinators in hardhat, we need to:

• Import the necessary dependencies

• Configure our network configuration

• Create a VRFCoordinator instance

• Call the createSubscription() function and pass it as an argument to the setSubId method

• Get the subid using the getSubId method

Hardhat Deployment Script (deploy.js)

const { network, ethers } = require("@nomiclab/hardhat");
// Configure our network configuration
const networks = {
hardhat: {
chainId: 1337,
// Add other network configurations as needed
},
};
// Import the VRF Coordinator library
const vrfCoordinatorV2_5Mock = require("./vrfCoordinatorV2_5Mock");
async function main() {
const { getChainId } = await ethers.getContractFactory("your-contract-name");
const contractInstance = await getChainId();
// Create a subscription instance from VRF Coordinator
const subscriptionInstance = await vrfCoordinatorV2_5Mock.createSubscription({
chainId: contractInstance.chainId,
provider: network.provider,
});
// Set subid using createSubscription()
await subscriptionInstance.setSubId("your-sub-id");
console.log(await vrfCoordinatorV2_5Mock.getSubId());
// Get subid using getSubId
const subid = await vrfCoordinatorV2_5Mock.getSubId();
console.log(subid);
}
main();

In this script, we first import the necessary dependencies and configure our network configuration. Then we create an instance of VRFCoordinator from VRF Coordinator version 2.5 Mock.

Then we create a subscription instance using createSubscription() and pass it as an argument to the setSubId method. This sets the subid for the specified contract.

Then we log the subid using getSubId and get the subid by calling getSubId directly on the VRF Coordinator instance.

Note: Replace "your-contract-name" with the actual name of your Ethereum contract and replace "your-sub-id" with your desired subid value. This script assumes you have the VRF Coordinator version 2.5 Mock implementation available.