feat: SQLExecutor-Klasse für die Ausführung von Roh-SQL-Abfragen mit Entity Framework Core hinzufügen

EnvelopeGenerator.Application/Contracts/SQLExecutor/ISQLExecutor.cs

@@ -0,0 +1,35 @@
+namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+
+/// <summary>
+/// Defines methods for executing raw SQL queries and mapping the results to <typeparamref name="TEntity"/> objects.
+/// </summary>
+/// <typeparam name="TEntity">The entity type to which the SQL query results will be mapped.</typeparam>
+public interface ISQLExecutor<TEntity>
+{
+    /// <summary>
+    /// Executes a raw SQL query and returns the first result or <c>null</c> if no result is found.
+    /// </summary>
+    /// <param name="sql">The raw SQL query to execute.</param>
+    /// <param name="cancellation">Optional cancellation token.</param>
+    /// <param name="parameters">Optional parameters for the SQL query.</param>
+    /// <returns>The first <typeparamref name="TEntity"/> result, or <c>null</c> if none found.</returns>
+    Task<TEntity?> ExecuteFirstAsync(string sql, CancellationToken cancellation = default, params object[] parameters);
+
+    /// <summary>
+    /// Executes a raw SQL query and expects a single result, or <c>null</c> if no result is found.
+    /// </summary>
+    /// <param name="sql">The raw SQL query to execute.</param>
+    /// <param name="cancellation">Optional cancellation token.</param>
+    /// <param name="parameters">Optional parameters for the SQL query.</param>
+    /// <returns>The single <typeparamref name="TEntity"/> result, or <c>null</c> if none found.</returns>
+    Task<TEntity?> ExecuteSingleAsync(string sql, CancellationToken cancellation = default, params object[] parameters);
+
+    /// <summary>
+    /// Executes a raw SQL query and returns all results as a collection of <typeparamref name="TEntity"/>.
+    /// </summary>
+    /// <param name="sql">The raw SQL query to execute.</param>
+    /// <param name="cancellation">Optional cancellation token.</param>
+    /// <param name="parameters">Optional parameters for the SQL query.</param>
+    /// <returns>An <see cref="IEnumerable{TEntity}"/> containing all matching results.</returns>
+    Task<IEnumerable<TEntity>> ExecuteAllAsync(string sql, CancellationToken cancellation = default, params object[] parameters);
+}

EnvelopeGenerator.Application/EnvelopeGenerator.Application.csproj

@@ -80,4 +80,8 @@
 	  </PackageReference>
 	</ItemGroup>
 
+	<ItemGroup>
+	  <Folder Include="Procedures\" />
+	</ItemGroup>
+
 </Project>

EnvelopeGenerator.Infrastructure/SQLExecutor.cs

@@ -0,0 +1,32 @@
+using EnvelopeGenerator.Application.Contracts.SQLExecutor.cs;
+using Microsoft.EntityFrameworkCore;
+
+namespace EnvelopeGenerator.Infrastructure;
+
+public sealed class SQLExecutor<T> : ISQLExecutor<T> where T : class
+{
+    private readonly EGDbContext _context;
+
+    public SQLExecutor(EGDbContext context)
+    {
+        _context = context;
+    }
+
+    public async Task<T?> ExecuteFirstAsync(string sql, CancellationToken cancellation = default, params object[] parameters)
+        => await _context
+                    .Set<T>()
+                    .FromSqlRaw(sql, parameters)
+                    .FirstOrDefaultAsync(cancellation);
+
+    public async Task<T?> ExecuteSingleAsync(string sql, CancellationToken cancellation = default, params object[] parameters)
+        => await _context
+                    .Set<T>()
+                    .FromSqlRaw(sql, parameters)
+                    .SingleOrDefaultAsync(cancellation);
+
+    public async Task<IEnumerable<T>> ExecuteAllAsync(string sql, CancellationToken cancellation = default, params object[] parameters)
+        => await _context
+                    .Set<T>()
+                    .FromSqlRaw(sql, parameters)
+                    .ToListAsync(cancellation);
+}