Using Wallets with Eidolon

The IWallet interface is used universally between Desktop, Mobile and WebGL builds. The only thing that differs is their constructors and recommended usage flow. Below we dive into how the interface is used for each platform!

WebGLWallet

When building for WebGL, the WebGLWallet class is compatible with most popular browser wallets following the JSON-RPC standard. It works seamlessly with wallets like MetaMask, TrustWallet, Enkrypt, and many others, providing users with a wide range of wallet options for interacting with your Unity-based blockchain game.

Eidolon Pro Tip!

Eidolon will connect to the default browser wallet set at any given time, allowing your players to choose from a variety of avaiable JSON-RPC based wallet providers. Now that’s powerful stuff!

Constructor

The WebGLWallet class has a constructor that initializes a new instance. You can use this constructor to create instances of wallet providers for different blockchains. Both single-chain and multi-chain constructors are dynamic and work even if mixed together in the same script. Feel free to creatively use this to create awesome experiences.

Single-Chain Constructor

// You can provide an empty constructor to have the wallet inherit the RPC set with the Project Settings.
WebGLWallet myWallet = new WebGLWallet()

Example:

// Reference to your contract
WebGLWallet wallet;

public void Awake()
{
    // Initialize an instance of the WebGLWallet class
    WebGLWallet wallet = new WebGLWallet();
}

Once your wallet instance has been instantiated, you can use it to invoke functions like Connect, SwitchChains, SendTransaction and so much more!

Multi-Chain Constructor

// Alternatively you can override the default RPC to instantiate a Wallet instance on a different network

// Custom RPC Provider
JsonRpcProvider provider = new JsonRpcProvider(" customRpcHere")

WebGLWallet myWallet = WebGLWallet(provider);

• provider (JsonRpcProvider): The RPC (Remote Procedure Call) endpoint URL of the blockchain network.

Example:

// Reference to your wallets
WebGLWallet ethereumWallet;
WebGLWallet skaleWallet;

public void Awake()
{
    // Create new JsonRpcProvider instances to be used for the differen networks.
    JsonRpcProvider ethRpc = new JsonRpcProvider("EthRpcHere");
    JsonRpcProvider skaleRpc = new JsonRpcProvider("SkaleRpcHere");

    // All of the below instances will use the RPC passed in the constructor.

    // Initialize an instance of your wallet on the Ethereum network
    ethereumWallet = new WebGLWallet(ethRpc);

    // Initialize an instance of your wallet on the SKALE network
    skaleWallet = new WebGLWallet(skaleRpc);

    // Let's use our instances

    // Use your Ethereum wallet instance to connect to the users default browser wallet to Ethereum
    string account = ethereumWallet.Connect("1");

    // Debug the account (optional)
    Debug.Log("Connected Account: " + account);
}

With the multi-chain constructor, you can connect to different blockchains and interact with smart contracts on those networks. It allows you to set a default network using the Project Setup window, whilst still allowing you to interact with contracts on other networks.

Methods

After instantiating your WebGLWallet instance, you can utilize any of the below wallet methods anywhere in your Unity project.

Connect

Connect(string chainId)

Method Description

Connects the wallet provider to a specific Ethereum network using the provided chain ID. THis function will return the connected public address.

Code Example

string chainId = "1"; // Main Ethereum Network (Change to the desired chain ID)
string account = wallet.Connect(chainId);

Debug.Log("Connected Account: " + account);

Parameter Explanation

• chainId (string): The chain ID of the target network.

Connect (Overload)

Connect(string chainId, string rpcUrl, string chainName, string nativeCurrencyName, string nativeCurrencySymbol, string nativeCurrencyDecimals, string blockExplorer)

Method Description

Connects the wallet provider to a specific network, adding the network if it’s not available on the users browser wallet. This function will return the connected public address.

Code Example

string chainId = "1351057110"; // SKALE Calypso Test Network (Change to the desired chain ID)
string rpcUrl = "https://testnet.skalenodes.com/v1/giant-half-dual-testnet"; // Replace with your RPC URL
string chainName = "SKALE Calypso Testnet";
string nativeCurrencyName = "sFUEL";
string nativeCurrencySymbol = "sFUEL";
string nativeCurrencyDecimals = "18";
string blockExplorer = "https://giant-half-dual-testnet.explorer.testnet.skalenodes.com/";

string account = wallet.Connect(chainId, rpcUrl, chainName, nativeCurrencyName, nativeCurrencySymbol, nativeCurrencyDecimals, blockExplorer);

Debug.Log("Connected Account: " + account);

Parameter Explanation

• chainId (string): The chain ID of the target network.
• rpcUrl (string): The RPC URL of the network.
• chainName (string): The name of the network.
• nativeCurrencyName (string): The native currency name.
• nativeCurrencySymbol (string): The native currency symbol.
• nativeCurrencyDecimals (string): The number of decimals for the native currency.
• blockExplorer (string): The URL of the block explorer for the network.

SwitchChains

SwitchChains(string chainId)

Method Description

Switches the connected Ethereum network to a different one using the specified chain ID.

Code Example

string chainId = "1351057110"; // SKALE Calypso Test Network (Change to the desired chain ID)
wallet.SwitchChains(chainId);

Parameter Explanation

• chainId (string): The chain ID of the target network.

SwitchChains (Overload)

SwitchChains(string chainId, string rpcURL, string chainName, string nativeCurrencyName, string nativeCurrencySymbol, string nativeCurrencyDecimals, string blockExplorer)

Method Description

Switches the connected network, adding the network if it’s not available on the users browser wallet.

Code Example

string chainId = "1564830818"; // SKALE Calyspo Mainnet Network (Change to the desired chain ID)
string rpcURL = "https://mainnet.skalenodes.com/v1/honorable-steel-rasalhague"; // Replace with your RPC URL
string chainName = "SKALE Calypso Mainnet";
string nativeCurrencyName = "sFUEL";
string nativeCurrencySymbol = "sFUEL";
string nativeCurrencyDecimals = "18";
string blockExplorer = "https://honorable-steel-rasalhague.explorer.mainnet.skalenodes.com/";

wallet.SwitchChainsAndAdd(chainId, rpcURL, chainName, nativeCurrencyName, nativeCurrencySymbol, nativeCurrencyDecimals, blockExplorer);

Parameter Explanation

• chainId (string): The chain ID of the target network.
• rpcURL (string): The RPC URL of the network.
• chainName (string): The name of the network.
• nativeCurrencyName (string): The native currency name.
• nativeCurrencySymbol (string): The native currency symbol.
• nativeCurrencyDecimals (string): The number of decimals for the native currency.
• blockExplorer (string): The URL of the block explorer for the network.

Disconnect

Disconnect()

Method Description

Disconnects from the currently connected wallet and clears the account information.

Code Example

wallet.Disconnect();

GetTransactionReceipt

GetTransactionReceipt()

Method Description

Retrieves the transaction receipt after sending a transaction.

Code Example

string transactionReceipt = wallet.GetTransactionReceipt();
Debug.Log("Transaction Receipt: " + transactionReceipt);

Parameter Explanation

• None

GetChainId

GetChainId()

Method Description

Retrieves the users current connected chain ID.

Code Example

string chainId = wallet.GetChainId();
Debug.Log("Current Chain: " + chainId);

Parameter Explanation

• None

SendTransaction

SendTransaction(string to, string gas = null, string gasPrice = null, string value = null, string nonce = null, string data = null)

Method Description

Sends a transaction to a smart contract method. Parameters like gas, gasPrice and value are optional. This function will return a transaction hash if successful, or an exception if not.

Eidolon Pro Tip!

This is considered to be a more advanced approach at sending transactions as it requires you to manually encode data. If you prefer an easier approach, please consider using the smart contract class.

Code Example

// Transfer 1 ETH to a user address by specifying the to address and the value in ETH.
string transactionHash = wallet.SendTransaction("WalletAddressHere", value: "1");

Parameter Explanation

• to (string): The address your sending the transaction to.
• gas (optional) (string): The gas limit for the transaction.
• gasPrice (optional) (string): The gas price for the transaction.
• value (optional) (string): The value for chain native tokens.
• nonce (optional) (string): The current transaction nonce count.
• data (optional): The encoded data for a contract method and set of parameters.

Sign Message

SignMessage(string message)

Method Description

Prompts the connected account to sign a message.

Eidolon Pro Tip!

Signing messages can be used to authenticate users. By proving ownership of a private key (without revealing it), a user can demonstrate that they are the legitimate owner of a particular account or address.

Code Example

// Prompt the connected account to sign a message and return the signature.
string signature = wallet.SignMessage("This is a test message!");

Parameter Explanation

• message (string): The message data you want the user to sign.

Embedded Wallet

When building for either Desktop or Mobile, the EmbeddedWallet class can be used and goes hand in hand with the Signer class.

The Signer class provides functionality to create and manage Ethereum accounts (wallets) for users within your Unity project. It includes methods for creating new accounts and loading existing ones. The class utilizes key storage mechanisms to store private keys and allows for interactive and invisible account creation and login.

By default, the generated keys are encrypted and stored within a Nethereum keystore. However, if you are developing on Android or Windows, you have the option to store the wallet file in the device-specific keystore, such as the Android Keystore or Windows Keystore.

Please note that in order to connect a signer to a session, you need to set it using the EmbeddedWallet class:

Single-Chain Constructor

EmbeddedWallet mySigner = new EmbeddedWallet(string privateKey);

• privateKey (string): The private key that will handle signing transactions.
• The chainID and RPC is automatically assigned based on your Project Setup configuration.

Multi-Chain Constructor

// Alternatively you can override the default RPC to instantiate a wallet instance on a different network

// Custom RPC Provider
JsonRpcProvider provider = new JsonRpcProvider("customRpcHere");

// Private Key
string privateKey = "abc...xyz";

// Chain ID
string chainId = "1";

EmbeddedWallet mySigner = new EmbeddedWallet(privateKey, chainId, provider);

• privateKey (string): The private key that will handle signing transactions.
• chainId (string): The chain ID that you want this signer to connect to.
• provider (JsonRpcProvider): The RPC (Remote Procedure Call) endpoint URL of the blockchain network.

This is important as it allows you to sign transactions to the blockchain from within your unity game. Let’s explore how we can use the signer class below:

Eidolon Pro Tip!

The Signer class in Eidolon is a popular approach for player accounts (or wallets) on mobile and desktop builds as it allows for truly seamless and invisible experiences.

Methods

After instantiating your Embedded Wallet instance, you can utilize any of the below wallet methods anywhere in your Unity project.

Create

The Create method allows developers to create a new Ethereum account (wallet) for a user. It takes a username and password as input parameters and performs the following steps:

1. Checks if a wallet with the provided username already exists.
2. If not, generates a new Ethereum private key and creates a wallet file.
3. Encrypts the private key using the provided password and stores it in your keystore of choice.

public static bool Create(string username, string password)

Load

The Load method enables developers to load an existing Ethereum account (wallet) for a user. It takes a username and an optional password (used for decryption) as input parameters and performs the following steps:

1. Checks if a wallet with the provided username exists.
2. If found, reads the KeyStore file and deserializes it.
3. Decrypts the private key using the provided password.
4. Provides you with access to the private key and public key for use in-game.

Please note that the public account can be accessed through PlayerPrefs.GetString("Account").

public static string Load(string username, string password = null)

WalletExists

The WalletExists method is a private helper method that checks if a wallet file exists for the given username.

private static bool WalletExists(string username)

Sign Message

SignMessage(string message)

Method Description

Prompts the connected account to sign a message.

Eidolon Pro Tip!

Signing messages can be used to authenticate users. By proving ownership of a private key (without revealing it), a user can demonstrate that they are the legitimate owner of a particular account or address.

Code Example

// Prompt the connected account to sign a message and return the signature.
string signature = wallet.SignMessage("This is a test message!");

Parameter Explanation

• message (string): The message data you want the user to sign.

---

Example Usage

This foundation allows you as a developer to have various different approaches when it comes to onboarding new or logging in existing users. Let’s explore two common ways of utilizing the signers class:

Interactive Login

With this example, we allow the player to sign up and login using a very traditional system. By manually passing their preferred username and password, they can manage their own account and store information where they think is best.

using TMPro;
using UnityEngine;

public class InteractiveLogin : MonoBehaviour
{
    // Input fields
    public TMP_InputField usernameInput;
    public TMP_InputField passwordInput;

    // RPC Provider
    public JsonRpcProvider provider;

    // Status Text
    public TextMeshProUGUI statusText;

    // Account variables
    private string username;
    private string password;

    public void Awake()
    {
        // Instantiate our RPC and use the default RPC from the project settings.
        provider = new JsonRpcProvider();
    }

    // Variables = Inputfield.value
    private void Update()
    {
        username = usernameInput.text;
        password = passwordInput.text;
    }

    // Used to sign-up a new player to your game.
    public void SignUp()
    {
        // Clear the input fields (optional)
        usernameInput.text = "";
        passwordInput.text = "";

        // We can call the BackgroundSigner class to create a new account for us based on the users input.
        bool SignUpSuccess = Signer.Create(username, password);

        // If the account is created successfully
        if (SignUpSuccess)
        {
            // Success logic goes here
            Debug.Log("Account created successfully!");
            statusText.text = "Account created successfully!";
        }
        // Otherwise
        else
        {
            // Failed logic goes here
            Debug.Log("Username already exists. Please choose a different username.");
            statusText.text = "Username already exists. Please choose a different username.";
        }
    }

    // Used to login an existing player based on their account details set at Sign-up
    public async void Login()
    {
        // The signer key used sign transactions in your game
        string signer = Signer.Load(username, password);

        // If the user logs in successfully
        if (signer != null)
        {
            // Success logic goes here
            Debug.Log("Logged in Successfully!");

            // You can create a new wallet intance using the logged in signer. Please see the smart contract example to see where a wallet is used.
            Wallet wallet = new Wallet(signer);

            // You can assign the public address for the wallet using the below
            string account = wallet.GetAddress();

            // The connected wallet can be retrieved with PlayerPrefs.GetString("Account")
            statusText.text = "Logged in Successfully! Connected Address: " + account;

            // Add any other logic required here. ie checking gas / sending gas.
            var currentGasBalance = await Provider.GetBalance(account);

            // Example showcasing how we would fetch the gas for this signer.
            Debug.Log("Signer Gas Balance: " + currentGasBalance);
        }
        // Otherwise
        else
        {
            // Failed logic goes here
            // The BackgroundSigner class will log errors for failed login attempts. Feel free to add more here.
            statusText.text = "Failed to login - Wallet doesn't exist! Please Sign-up first!";
        }
    }
}

The Interactive login example provides a user-friendly interface for account creation and login while connecting to Ethereum blockchain features, allowing for seamless interaction with decentralized applications.

Invisible Login

With this example, we generate a wallet ID and secret which is then stored within the device keystore for secure long-term storage. This allows you as the developer to create seamless background login flows which don’t require any input from your players.

using TMPro;
using UnityEngine;

public class InvisibleLogin : MonoBehaviour
{
    // Variables
    public TextMeshProUGUI statusText;
    private string ID;
    public JsonRpcProvider provider;

    // We can create a new invisible signer by calling the Signer.Create() method.
    public void CreateAccount()
    {
        // Instantiate our RPC and use the default RPC from the project settings.
        provider = new JsonRpcProvider();

        // We can use anything to identify the signer -IP/MAC Address, GUID - In this example we use a unique, persistent device ID.
        ID = SystemInfo.deviceUniqueIdentifier;

        // Generate a new secret to secure the signer. We can pass a length to our PasswordGenerator class.
        string secret = PasswordGenerator.GenerateRandomPassword(32);

        // Create the signer
        bool AccountCreated = Signer.Create(ID, secret);

        // If the signer has been created...
        if (AccountCreated)
        {
            statusText.text = "Account created successfully with ID: " + ID;

            // Add any other logic required here. ie checking gas / sending gas.

            // In our example we'll just login
            Invoke(nameof(LoadAccount), 4f);
        }
        // Otherwise if the ID already exists, we can login.
        else
        {
           LoadAccount();
        }
    }

    public async void LoadAccount()
    {
        // Load our private key using the Signer.Load() method.
        string signer = Signer.Load(ID, WindowsKeystore.GetStringFromKeystore(ID));

        // If the signer value isn't empty..
        if (signer != null)
        {
            // You can create a new wallet intance using the logged in signer. Please see the smart contract example to see where a wallet is used.
            Wallet wallet = new Wallet(signer);

            // You can assign the public address for the wallet using the below
            string account = wallet.GetAddress();

            // Sanity check to ensure we're connected.
            statusText.text = "Account: " + account + " logged in successfully!";

            // Add any other logic required here. ie checking gas / sending gas.
            var currentGasBalance = await Provider.GetBalance(account);

            // Example showcasing how we would fetch the gas for this signer.
            Debug.Log("Signer Gas Balance: " + currentGasBalance);

            // You can go even further and add a conditional statement so that if the signer has < X amount of gas
            // You can send it gas using an API or your preferred method for gas distribution.
        }
        // Otherwise if the key is empty..
        else
        {
            // There is error handling in the core library, but the developer can add extra here for debugging.
            statusText.text = "Couldn't log in";
        }
    }
}

The InvisibleLogin class provides a method for developers to create and manage Ethereum accounts on behalf of players, allowing them to seamlessly interact with decentralized applications without the need for players to handle username and password creation.