15.4 Building a Reusable SDK Layer

In production applications, developers often build an SDK layer to encapsulate blockchain interactions. This approach abstracts low-level logic and provides reusable functions across the application.

A basic SDK structure might include:

• network initialization

• contract interaction methods

• transaction helpers

• error handling

Below is a simplified example of a FreCx SDK module.

class FreCxSDK {
  constructor(rpcUrl, privateKey) {
    this.provider = new ethers.JsonRpcProvider(rpcUrl);
    this.wallet = new ethers.Wallet(privateKey, this.provider);
  }

  async getBalance(address) {
    const balance = await this.provider.getBalance(address);
    return ethers.formatEther(balance);
  }

  async sendTransaction(to, amount) {
    const tx = await this.wallet.sendTransaction({
      to,
      value: ethers.parseEther(amount)
    });
    return tx.hash;
  }
}

module.exports = FreCxSDK;

This structure allows developers to reuse common functionality without repeating low-level logic.