Add Domain project and shifted handlers to application.

wolverine/a-frame-architecture/FinancialApi.Application/Account.cs

@@ -1,70 +0,0 @@
-namespace FinancialApi.Application;
-
-public record Account(int Id, decimal Balance, string AccountType)
-{
-    public Account ApplyPosting(decimal amount, EntryType entryType)
-    {
-        if (amount <= 0)
-        {
-            throw new ArgumentException("Credit amount must be positive.");
-        }
-
-        var newBalance = Balance;
-        if (AccountType == "Revenue")
-        {
-            newBalance = entryType == EntryType.Credit ? newBalance + amount : newBalance - amount;
-        }
-        else
-        {
-            newBalance = entryType == EntryType.Debit ? newBalance - amount : newBalance + amount;
-        }
-        
-
-        if (newBalance < 0 && AccountType == "Liability")
-        {
-            throw new InvalidOperationException("Insufficient funds.");
-        }
-
-        return this with { Balance = newBalance };
-    }
-
-    public Account ApplyFee(decimal amount)
-    {
-        if (amount <= 0)
-        {
-            throw new ArgumentException("Fee must be positive.");
-        }
-
-        if (Balance - amount < 0)
-        {
-            throw new InvalidOperationException("Insufficient funds.");
-        }
-
-        return this with { Balance = Balance - amount };
-    }
-
-    public Account Debit(decimal amount)
-    {
-        if (amount <= 0)
-        {
-            throw new ArgumentException("Debit amount must be positive.");
-        }
-
-        if (Balance - amount < 0)
-        {
-            throw new InvalidOperationException("Insufficient funds.");
-        }
-
-        return this with { Balance = Balance - amount };
-    }
-
-    public Account Credit(decimal amount)
-    {
-        if (amount <= 0)
-        {
-            throw new ArgumentException("Credit amount must be positive.");
-        }
-
-        return this with { Balance = Balance + amount };
-    }
-}

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

@@ -0,0 +1,58 @@
+using FinancialApi.Domain;
+using Wolverine.Attributes;
+using Wolverine.Persistence;
+
+namespace FinancialApi.Application;
+
+public record ApplyFeeCommand(int AccountId, decimal Amount);
+
+public record FeeAppliedEvent(int AccountId, decimal Amount);
+
+public static class ApplyFeeHandler
+{
+    public static async Task<(Account, Account)> LoadAsync(
+        ApplyFeeCommand cmd,
+        IAccountQuery query)
+    {
+        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 (source, dest);
+    }
+
+    public static (
+        IStorageAction<Account> CustomerWrite,
+        IStorageAction<Account> RevenueWrite,
+        IStorageAction<JournalEntry> JournalWrite,
+        FeeAppliedEvent Event
+        )
+        Handle(
+            ApplyFeeCommand cmd,
+            Account source,
+            Account dest
+        )
+    {
+        var updatedSource = source.ApplyPosting(cmd.Amount, EntryType.Debit);
+        var updatedRevenue = dest.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}",
+            DateTimeOffset.UtcNow, lines);
+
+        var @event = new FeeAppliedEvent(cmd.AccountId, cmd.Amount);
+
+        return (
+            Storage.Update(updatedSource),
+            Storage.Update(updatedRevenue),
+            Storage.Insert(journalEntry.Entry),
+            @event
+        );
+    }
+}

wolverine/a-frame-architecture/FinancialApi.Application/BalancedJournal.cs

@@ -1,23 +0,0 @@
-namespace FinancialApi.Application;
-
-public record BalancedJournal
-{
-    public JournalEntry Entry { get; }
-
-    private BalancedJournal(JournalEntry entry) => Entry = entry;
-
-    public static BalancedJournal Create(Guid id, string description, DateTimeOffset createdAt, List<JournalLine> lines)
-    {
-        var debits = lines.Where(l => l.Type == EntryType.Debit).Sum(l => l.Amount);
-        var credits = lines.Where(l => l.Type == EntryType.Credit).Sum(l => l.Amount);
-
-        if (debits != credits)
-        {
-            throw new InvalidOperationException(
-                $"GAAP Violation: Total Debits ({debits}) must equal Total Credits ({credits})!"
-            );
-        }
-
-        return new(new JournalEntry(id, description, createdAt, lines));
-    }
-}

wolverine/a-frame-architecture/FinancialApi.Application/EntryType.cs

@@ -1,7 +0,0 @@
-namespace FinancialApi.Application;
-
-public enum EntryType
-{
-    Debit,
-    Credit
-}

wolverine/a-frame-architecture/FinancialApi.Application/FinancialApi.Application.csproj

@@ -6,4 +6,14 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <ProjectReference Include="..\FinancialApi.Domain\FinancialApi.Domain.csproj" />
+    </ItemGroup>
+
+    <ItemGroup>
+      <Reference Include="Wolverine">
+        <HintPath>..\..\..\..\..\..\.nuget\packages\wolverinefx\6.18.0\lib\net10.0\Wolverine.dll</HintPath>
+      </Reference>
+    </ItemGroup>
+
 </Project>

wolverine/a-frame-architecture/FinancialApi.Application/JournalEntry.cs

@@ -1,21 +0,0 @@
-namespace FinancialApi.Application;
-
-public record JournalEntry
-{
-    public Guid Id { get; init; }
-    public string Description { get; init; }
-    public DateTimeOffset CreatedAt { get; init; }
-    public List<JournalLine> Lines { get; init; } = [];
-
-    private JournalEntry()
-    {
-    }
-
-    internal JournalEntry(Guid id, string description, DateTimeOffset createdAt, List<JournalLine> lines)
-    {
-        Lines = lines;
-        Id = id;
-        Description = description;
-        CreatedAt = createdAt;
-    }
-}

wolverine/a-frame-architecture/FinancialApi.Application/JournalLine.cs

@@ -1,3 +0,0 @@
-namespace FinancialApi.Application;
-
-public record JournalLine(int AccountId, decimal Amount, EntryType Type);

wolverine/a-frame-architecture/FinancialApi.Application/TransferFundsHandler.cs

@@ -0,0 +1,60 @@
+using FinancialApi.Domain;
+using Wolverine.Attributes;
+using Wolverine.Persistence;
+
+namespace FinancialApi.Application;
+
+public interface IAccountQuery
+{
+    Task<Account?> FindByIdAsync(int id);
+}
+
+public record TransferFundsCommand(int SourceAccountId, int DestinationAccountId, decimal Amount);
+
+public record FundsTransferredEvent(int SourceAccountId, int DestinationAccountId, decimal Amount);
+
+public record TransferPair(Account Source, Account Destination);
+
+public static class TransferFundsHandler
+{
+    public static async Task<TransferPair?> LoadAsync(TransferFundsCommand cmd, IAccountQuery query)
+    {
+        var source = await query.FindByIdAsync(cmd.SourceAccountId);
+        var dest = await query.FindByIdAsync(cmd.DestinationAccountId);
+
+        if (source == null || dest == null) return null;
+
+        return new TransferPair(source, dest);
+    }
+
+    public static (
+        IStorageAction<Account> SourceWrite,
+        IStorageAction<Account> DestWrite,
+        IStorageAction<JournalEntry> JournalWrite,
+        FundsTransferredEvent Event
+        ) Handle(TransferFundsCommand cmd, TransferPair pair)
+    {
+        var updatedSource = pair.Source.Debit(cmd.Amount);
+        var updatedDest = pair.Destination.Credit(cmd.Amount);
+
+        var lines = new List<JournalLine>
+        {
+            new (pair.Source.Id, cmd.Amount, EntryType.Debit),
+            new (pair.Destination.Id, cmd.Amount, EntryType.Credit)
+        };
+
+        var journalEntry =
+            BalancedJournal.Create(Guid.NewGuid(),
+                $"Transfer: {cmd.Amount} from {cmd.SourceAccountId} to {cmd.DestinationAccountId}",
+                DateTimeOffset.UtcNow, lines);
+
+        var @event = new FundsTransferredEvent(cmd.SourceAccountId, cmd.DestinationAccountId, cmd.Amount);
+
+        return (
+            Storage.Update(updatedSource),
+            Storage.Update(updatedDest),
+            Storage.Insert(journalEntry.Entry),
+            @event
+        );
+    }
+}