The Keypom Multichain Trial Accounts SDK provides a seamless way to create and manage trial accounts across multiple blockchain networks, including NEAR and EVM-compatible chains. This SDK abstracts the complexities involved in setting up trial accounts, managing their constraints, and performing actions on their behalf. With this package, you can:

• Deploy and manage trial contracts.
• Create trials with customizable constraints per chain.
• Add and activate trial accounts with limited access keys.
• Perform actions on behalf of trial accounts, including contract calls on NEAR and EVM chains.
• Broadcast transactions signed via Multi-Party Computation (MPC).
• Handle usage statistics, exit conditions, and expiration for trial accounts.

Table of Contents

• Installation
• Getting Started
  • Prerequisites
  • Initialization
• Usage Examples
  • Creating a Trial
  • Adding and Activating Trial Accounts
  • Performing Actions
• Configuration
• Scripts and Commands
• Concepts
  • Trial Accounts
  • MPC Integration
  • Usage Constraints
• Utilities
• Contributing
• License

Installation

To install the Keypom Multichain Trial Accounts SDK, run one of the following commands:

npm install @keypom/trial-accounts
# or
yarn add @keypom/trial-accounts
# or
pnpm add @keypom/trial-accounts

Getting Started

Prerequisites

• Node.js: Ensure you have Node.js installed (version 14 or higher recommended).
• NEAR CLI: Install the NEAR CLI for interacting with NEAR blockchain.
• EVM Provider: For EVM interactions, you'll need access to an EVM-compatible network (e.g., Base Sepolia) and an API key from a provider like Alchemy.

Initialization

Before using the SDK, you need to initialize the TrialAccountManager class. This class provides methods to manage trial accounts and interact with the trial contract.

import { TrialAccountManager } from "@keypom/trial-accounts";
import { Near, Account } from "@near-js/wallet-account";
import { UnencryptedFileSystemKeyStore } from "@near-js/keystores-node";
import path from "path";
import os from "os";

// Set up NEAR connection
const homedir = os.homedir();
const credentialsPath = path.join(homedir, ".near-credentials");
const keyStore = new UnencryptedFileSystemKeyStore(credentialsPath);
const near = new Near({
    networkId: "testnet",
    keyStore,
    nodeUrl: "https://rpc.testnet.near.org",
});

const signerAccount = await near.account("your-account.testnet");

const trialManager = new TrialAccountManager({
    trialContractId: "trial-contract.your-account.testnet",
    mpcContractId: "v1.signer-prod.testnet",
    signerAccount,
    near,
});

• trialContractId: The account ID where the trial contract is deployed.
• mpcContractId: The account ID of the MPC contract.
• signerAccount: An instance of Account used for signing transactions.
• near: The NEAR connection instance.

Usage Examples

Creating a Trial

Create a new trial with specific constraints per chain. For example, you can set different allowed methods and contracts for NEAR and EVM chains.

import { TrialData } from "@keypom/trial-accounts";
import { parseEther } from "ethers";
import { parseNearAmount } from "@near-js/utils";

const trialData: TrialData = {
  constraintsByChainId: {
    EVM: {
      chainId: 84532,
      allowedMethods: ["setMessage"],
      allowedContracts: ["0xdf5c3bd628a11C97BB25d441D8b6d9Ce974dc552"],
      maxGas: 1000000,
      maxValue: "0",
      initialDeposit: parseEther("0.004"), // approximately $15 worth of ETH
    },
    NEAR: {
      allowedMethods: ["add_message"],
      allowedContracts: ["guestbook.near-examples.testnet"],
      maxGas: null,
      maxDeposit: null,
      initialDeposit: parseNearAmount("10")!, // 10 NEAR tokens
    },
  },
  usageConstraints: null,
  interactionLimits: null,
  exitConditions: null,
  expirationTime: null,
};

// Create the trial
const trialId = await trialManager.createTrial(trialData);
console.log(`Trial created with ID: ${trialId}`);

Adding and Activating Trial Accounts

Add trial accounts to the trial by generating limited access keys and then activate them.

// Add trial accounts
const numberOfKeys = 1;
const trialKeys = await trialManager.addTrialAccounts(numberOfKeys);
console.log(`Added ${trialKeys.length} trial account(s).`);

// Activate the trial account for a specific chain (e.g., NEAR or EVM)
const trialKey = trialKeys[0];
const chainId = "NEAR"; // or "84532" for EVM chain
const accountId = `trial-account-${Date.now()}.testnet`;

trialManager.setTrialAccountCredentials(
    accountId,
    trialKey.trialAccountSecretKey
);
await trialManager.activateTrialAccounts(accountId, chainId);
console.log(`Trial account ${accountId} activated.`);

Performing Actions

Perform actions on behalf of the trial account, such as calling methods on contracts. The SDK ensures that the actions are within the specified constraints.

import { ActionToPerform } from "@keypom/trial-accounts";
import { BASE_GUESTBOOK_ABI } from "./abis/baseGuestbook";

// Define the action to perform on the EVM chain
const action: ActionToPerform = {
    chain: "EVM",
    chainId: 84532, // Base Sepolia chain ID
    targetContractId: "0xdf5c3bd628a11C97BB25d441D8b6d9Ce974dc552",
    methodName: "setMessage",
    args: ["Hello from the trial account!"],
    abi: BASE_GUESTBOOK_ABI,
    value: "0",
    accessList: [],
};

// Request signature and perform the action
const providerUrl = `https://base-sepolia.g.alchemy.com/v2/YOUR_ALCHEMY_API_KEY`;
const { signatures, txnDatas } = await trialManager.performActions(
    [action],
    providerUrl
);

// Broadcast the transaction
const { result } = await trialManager.broadcastTransaction({
    actionToPerform: action,
    signatureResult: signatures[0],
    signerAccountId: accountId,
    providerUrl,
    txnData: txnDatas[0],
});

console.log("Action performed successfully.");

Configuration

You can customize various settings, such as retry logic and configurations for different chains.

// Set custom retry logic
trialManager.setRetryConfig({
    maxRetries: 5,
    initialDelayMs: 2000,
    backoffFactor: 2,
});

// Set trial account credentials if needed
trialManager.setTrialAccountCredentials("trial-account.testnet", "ed25519:...");

// Set trial ID
trialManager.setTrialId(123);

• maxRetries: Maximum number of retries for operations.
• initialDelayMs: Initial delay before retrying (in milliseconds).
• backoffFactor: Exponential backoff factor.

Scripts And Commands

The package includes several scripts to automate common tasks. You can run these scripts using commands defined in the package.json.

pnpm run deploy:evm
pnpm run deploy:near
pnpm run deploy:omni

These scripts correspond to configurations defined in the configs directory:

• nearSimple: For NEAR-only trials.
• evmSimple: For EVM-only trials.
• omniChainSimple: For trials that span both NEAR and EVM chains.

Running the Scripts

1. Ensure Environment Variables are Set: Create a .env file in the root directory with the necessary environment variables, especially for EVM interactions.

   EVM_PRIVATE_KEY=your_evm_private_key
   ALCHEMY_API_KEY=your_alchemy_api_key

2. Install Dependencies:

   pnpm install

3. Run the scripts:

   pnpm run deploy:evm
   pnpm run deploy:near
   pnpm run deploy:omni

The script will:

• Initialize the NEAR connection.
• Create a trial with specified constraints.
• Add and activate trial accounts.
• Perform the defined actions.
• Output the results and write data to the data directory.

Concepts

Trial Accounts

Trial accounts are temporary accounts with limited access, ideal for onboarding new users or running promotions. They use limited access keys to ensure they operate within specified constraints.

• Limited Access Keys: These keys allow calling specific methods on the trial contract.

MPC Integration

The SDK integrates with a Multi-Party Computation (MPC) service to securely sign transactions without exposing private keys.

• MPC Contract: The mpcContractId points to the deployed MPC contract that handles signing.
• Signature Requests: When performing actions, the SDK requests signatures from the MPC contract, ensuring secure transaction signing.

Usage Constraints

When creating a trial, you can specify various constraints to control how trial accounts interact with the blockchain.

• Constraints by Chain ID: Define constraints specific to each chain (NEAR, EVM, etc.).
• Allowed Methods and Contracts: Restrict which methods and contracts trial accounts can interact with.
• Gas and Value Limits: Set maximum gas usage and transaction values.
• Initial Deposits: Fund trial accounts automatically upon activation.

Example:

const trialData: TrialData = {
    constraintsByChainId: {
        EVM: {
            chainId: 84532,
            allowedMethods: ["setMessage"],
            allowedContracts: ["0xdf5c3bd628a11C97BB25d441D8b6d9Ce974dc552"],
            maxGas: 1000000,
            maxValue: "0",
            initialDeposit: parseEther("0.004"),
        },
    },
    usageConstraints: null,
    interactionLimits: null,
    exitConditions: null,
    expirationTime: null,
};

Contributing

We welcome contributions to the Keypom Trial Accounts SDK! Please follow these guidelines:

• Bug Reports: Submit detailed bug reports with steps to reproduce.
• Feature Requests: Open issues for feature enhancements with use cases.
• Pull Requests: Ensure your code passes linting and tests before submitting.

License

This project is licensed under the GPL License.

Thank you for using the Keypom Trial Accounts SDK! If you have any questions or need assistance, feel free to join our community or open an issue on GitHub.