NCQRS: how do you load from the domain?

Question

Take the standard registration process:

1. user signs up

2. user is sent email with link activate account

3. user activates account

the issue i'm talking about is:

• when we create the initial account we store the username, password, email, activation key

• when the user clicks the activation key link we validate the key using the readmodel

• we then fire the ActivateAccountCommand passing in the username

how do i load the users account to activate it in the domain?

---

initially I wanted to pass the new users Acount.Id to the readmodel but there is no access (that i'm aware of) from within the CommandExecutorBase - we don't save this:

protected override void ExecuteInContext(IUnitOfWorkContext context,
       CreateAccountViaFormRegistrationCommand command)
{
    var newKey = Guid.NewGuid().ToString();
    var newAccount = new Account(
            command.UserName, command.Email, command.Password, newKey);
    SendWelcomeEmail(command.Email, command.UserName, newKey);
    context.Accept();
}  

Answer 1

You can publish an AccountActivationKeySent event, which in turn can be handled to populate whatever projection you need on the read side. Something along the lines of:

// 1. Create and send the command from your client:

var command = new CreateAccountViaFormRegistrationCommand {
    AccountId = Guid.NewGuid(),
    ...
}

// 2. Create a new account in your command handler

var newAccount = new Account(command.AccountId, ...);
context.Accept();

// 3. And your account constructor (assuming it's inheriting from one
//    of EventSource's subclasses, e.g. AggregateRootMappedByConvention) 
//    might look like this:

public Account(Guid accountId, string name, ...) {
  EventSourceId = accountId;
  ApplyEvent(new AccountCreated { AccountId = Id, ... } );
  ApplyEvent(new AccountActivationSent { AccountId = Id, ... })
}