Create user accounts

For this course, we want to focus on building a marketplace, and token transfers are the main focus, so we will simplify account creation a bit.

If you are interested in learning more about how to register accounts using EVM wallets, the process is described in detail in our News feed dapp course, which you can find here.

Configure FT4 account module

To configure FT4 for accounts, we add the following configuration to the lib.ft4.core.accounts module.

chromia.yml

blockchains:
  rell-marketplace:
    module: main
    moduleArgs:
      lib.ft4.core.accounts:
        rate_limit:
          max_points: 10
          recovery_time: 5000
          points_at_account_creation: 2

Setting rate-limit points_at_account_creation means that a user can at most perform 2 operations per time unit. The recovery time for these points can be set using recovery_time property which defaults to 5000ms. We can also configure the max_points an account can have or disable rate limiting altogether by setting active to false.

Start the node to verify if the configuration file is set up correctly by running the command chr node start and querying the config using chr query ft4.get_config.

Create a user account

Now that our configurations are set, we can continue registering a user account.

We will do this by creating an operation which creates and account with 1000 tokens. Let's add some imports to rell_marketplace/module.rell

rell_marketplace/module.rell

import lib.ft4.core.accounts.{ account, create_account_with_auth, single_sig_auth_descriptor };

and create a new file rell_marketplace/accounts.rell and add the following:

rell_marketplace/accounts.rell

operation create_user(pubkey) {
    val account = create_account_with_auth(single_sig_auth_descriptor(pubkey, set(["A", "T"])));
    Unsafe.mint(account, dapp_meta.asset, 1000);
}

The operation creates an account for a specific pubkey and adds an auth descriptor with flags A and T. This means the registered key can be used to perform administrator commands such as adding and removing other auth descriptors and performing transfers. Then, the operation mints 1000 tokens on the account. Note this this is just for testing and learning purpose, so we dont have to take any other security measures when it comes to creating tokens and accounts.

If you want to learn more how to handle auth descriptors and accounts, you can take the course Create a simple app on Chromia using Rell and React.

Next, we will look at an NFT model, the asset we want to trade in our marketplace.