Added a-frame-architecture usiung wolverine sample.

wolverine/a-frame-architecture/FinancialApi.Application/Handlers/ApplyFeeHandler.cs

@@ -0,0 +1,51 @@
+using FinancialApi.Application.Commands;
+using FinancialApi.Application.Interfaces;
+using FinancialApi.Application.Models;
+using FinancialApi.Domain.Aggregates;
+using FinancialApi.Domain.Entities;
+using FinancialApi.Domain.Events;
+using Wolverine.Persistence;
+
+namespace FinancialApi.Application.Handlers;
+
+public static class ApplyFeeHandler
+{
+    public static async Task<FeeContext> LoadAsync(ApplyFeeCommand cmd, IAccountQuery query, TimeProvider timeProvider)
+    {
+        var source = await query.FindByIdAsync(cmd.AccountId);
+        var dest = await query.FindByIdAsync(99999);
+        if (source == null || dest == null)
+        {
+            throw new InvalidOperationException("Cannot process transfer. Account(s) not found.");
+        }
+
+        return new FeeContext(source, dest, timeProvider.GetUtcNow());
+    }
+
+    public static ( IStorageAction<Account> CustomerWrite, IStorageAction<Account> RevenueWrite,
+        IStorageAction<BalancedJournalEntry> JournalWrite, FeeAppliedEvent Event ) Handle(
+            ApplyFeeCommand cmd,
+            FeeContext context
+        )
+    {
+        var updatedSource = context.Source.ApplyPosting(cmd.Amount, EntryType.Debit);
+        var updatedRevenue = context.Destination.ApplyPosting(cmd.Amount, EntryType.Credit);
+
+        var lines = new List<JournalLine>
+        {
+            new(updatedSource.Id, cmd.Amount, EntryType.Debit), new(updatedRevenue.Id, cmd.Amount, EntryType.Credit)
+        };
+
+        var journalEntry = BalancedJournal.Create(
+            Guid.NewGuid(),
+            $"Service Fee Applied: {cmd.Amount} to Account {cmd.AccountId}",
+            context.TimeStamp,
+            lines
+        );
+
+        var @event = new FeeAppliedEvent(cmd.AccountId, cmd.Amount);
+
+        return (Storage.Update(updatedSource), Storage.Update(updatedRevenue), Storage.Insert(journalEntry.Entry),
+            @event);
+    }
+}