Instantiating a Smart Contract

The getContract function is your gateway to creating and interacting with contract instances on OP_NET. By utilizing this function, you ensure that your contract instance is correctly typed and capable of interacting seamlessly with its ABI-defined methods.

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Method

getContract<T extends BaseContractProperties>(
   address: string | Address,
   abi: BitcoinInterface | BitcoinInterfaceAbi,
   provider: AbstractRpcProvider,
   network: Network,
   sender?: Address
): BaseContract<T> & Omit<T, keyof BaseContract<T>>;

• Parameters:

  • address: string | Address: The address of the contract to instantiate.
  • abi: BitcoinInterface | BitcoinInterfaceAbi: The ABI of the contract.
  • provider: AbstractRpcProvider: The provider instance connected to OP_NET.
  • network: Network: The target network for the contract.
  • sender?: Address: (Optional) The sender address for contract interactions.

• Returns:

  • BaseContract<T>: The contract instance with all methods, events, and properties defined in the ABI.
  • Omit<T, keyof BaseContract<T>>: The contract interface without the methods and events inherited from the base contract.

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Example of Instantiating a Contract

Instantiating with a String Address

import { getContract, IOP_20Contract, OP_20_ABI } from "opnet";
import { networks } from "@btc-vision/bitcoin";

const op20Contract = getContract<IOP_20Contract>(
  "bcrt1qexampleaddress", // Contract address as a string
  OP_20_ABI, // OP_20 token contract ABI
  provider, // JSONRpcProvider connected to OP_NET
  networks.regtest // Target network
  // Optional: Add the sender's address
  // Address.fromString("your-public-key")
);

Instantiating with an Address Object

const op20Contract = getContract<IOP_20Contract>(
  contractAddressObject, // Address object resolved via getPublicKeyInfo or other methods
  OP_20_ABI,
  provider,
  networks.regtest
  // Optional: Add the sender's address
  // Address.fromString("your-public-key")
);

In both cases, the returned instance allows you to interact with the OP_20 token contract, using methods defined in its ABI (e.g., balanceOf, transfer).

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Best Practices

• Specify the expected contract interface (e.g., IOP_20Contract) to enable full IntelliSense support and reduce runtime errors.
• Create and reuse a single instance of your JSONRpcProvider for consistent connectivity and improved performance.
• Set the sender parameter explicitly if your contract interactions require it, otherwise, leave it unset for general use.

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What’s Next?

Now that you understand the basics, explore the following topics to dive deeper into contract interactions:

• Simulating a Transaction with a Contract Instance