Files
silver-octo-spoon/wolverine/a-frame-architecture/FinancialApi.Infrastructure/TransferFundsHandler.cs
T

43 lines
1.7 KiB
C#

using FinancialApi.Application;
using Microsoft.EntityFrameworkCore;
using Wolverine.Attributes;
using Wolverine.Persistence;
namespace FinancialApi.Infrastructure;
public record TransferFundsCommand(int SourceAccountId, int DestinationAccountId, decimal Amount);
public record FundsTransferredEvent(int SourceAccountId, int DestinationAccountId, decimal Amount);
// A simple container to pass our loaded entities into the pure function
public record TransferPair(Account Source, Account Destination);
public static class TransferFundsHandler
{
public static async Task<TransferPair?> LoadAsync(TransferFundsCommand cmd, AccountDbContext db)
{
var source = await db.Accounts.AsNoTracking().FirstOrDefaultAsync(x => x.Id == cmd.SourceAccountId);
var dest = await db.Accounts.AsNoTracking().FirstOrDefaultAsync(x => x.Id == cmd.DestinationAccountId);
if (source == null || dest == null) return null; // Wolverine drops into a 404/Problem if null
return new TransferPair(source, dest);
}
[Transactional]
public static (
IStorageAction<Account> SourceWrite,
IStorageAction<Account> DestWrite,
FundsTransferredEvent Event
) Handle(TransferFundsCommand cmd, TransferPair pair)
{
var updatedSource = pair.Source.Debit(cmd.Amount);
var updatedDest = pair.Destination.Credit(cmd.Amount);
var sourcePersistence = Storage.Update(updatedSource);
var destPersistence = Storage.Update(updatedDest);
var @event = new FundsTransferredEvent(cmd.SourceAccountId, cmd.DestinationAccountId, cmd.Amount);
return (sourcePersistence, destPersistence, @event);
}
}