Create DataTableBuilder (#4608)

* Add DataTableBuilder Using Expressions

* Format

* Unwrap Underlying Enum Type

* Formatting

src/Infrastructure.Dapper/DapperHelpers.cs

@@ -1,4 +1,8 @@
-using System.Data;
+using System.Collections.Frozen;
+using System.Data;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq.Expressions;
+using System.Reflection;
 using Bit.Core.Entities;
 using Bit.Core.Models.Data;
 using Dapper;
@@ -7,8 +11,148 @@ using Dapper;
 
 namespace Bit.Infrastructure.Dapper;
 
+/// <summary>
+/// Provides a way to build a <see cref="DataTable"/> based on the properties of <see cref="T"/>.
+/// </summary>
+/// <typeparam name="T"></typeparam>
+public class DataTableBuilder<T>
+{
+    private readonly FrozenDictionary<string, (Type Type, Func<T, object?> Getter)> _columnBuilders;
+
+    /// <summary>
+    /// Creates a new instance of <see cref="DataTableBuilder{T}"/>.
+    /// </summary>
+    /// <example>
+    /// <code>
+    /// new DataTableBuilder<MyObject>(
+    ///     [
+    ///         i => i.Id,
+    ///         i => i.Name,
+    ///     ]
+    /// );
+    /// </code>
+    /// </example>
+    /// <param name="columnExpressions"></param>
+    /// <exception cref="ArgumentException"></exception>
+    public DataTableBuilder(Expression<Func<T, object?>>[] columnExpressions)
+    {
+        ArgumentNullException.ThrowIfNull(columnExpressions);
+        ArgumentOutOfRangeException.ThrowIfZero(columnExpressions.Length);
+
+        var columnBuilders = new Dictionary<string, (Type Type, Func<T, object?>)>(columnExpressions.Length);
+
+        for (var i = 0; i < columnExpressions.Length; i++)
+        {
+            var columnExpression = columnExpressions[i];
+
+            if (!TryGetPropertyInfo(columnExpression, out var propertyInfo))
+            {
+                throw new ArgumentException($"Could not determine the property info from the given expression '{columnExpression}'.");
+            }
+
+            // Unwrap possible Nullable<T>
+            var type = Nullable.GetUnderlyingType(propertyInfo.PropertyType) ?? propertyInfo.PropertyType;
+
+            // This needs to be after unwrapping the `Nullable` since enums can be nullable
+            if (type.IsEnum)
+            {
+                // Get the backing type of the enum
+                type = Enum.GetUnderlyingType(type);
+            }
+
+            if (!columnBuilders.TryAdd(propertyInfo.Name, (type, columnExpression.Compile())))
+            {
+                throw new ArgumentException($"Property with name '{propertyInfo.Name}' was already added, properties can only be added once.");
+            }
+        }
+
+        _columnBuilders = columnBuilders.ToFrozenDictionary();
+    }
+
+    private static bool TryGetPropertyInfo(Expression<Func<T, object?>> columnExpression, [MaybeNullWhen(false)] out PropertyInfo property)
+    {
+        property = null;
+
+        // Reference type properties
+        // i => i.Data
+        if (columnExpression.Body is MemberExpression { Member: PropertyInfo referencePropertyInfo })
+        {
+            property = referencePropertyInfo;
+            return true;
+        }
+
+        // Value type properties will implicitly box into the object so 
+        // we need to look past the Convert expression
+        // i => (System.Object?)i.Id
+        if (
+            columnExpression.Body is UnaryExpression
+            {
+                NodeType: ExpressionType.Convert,
+                Operand: MemberExpression { Member: PropertyInfo valuePropertyInfo },
+            }
+        )
+        {
+            // This could be an implicit cast from the property into our return type object?
+            property = valuePropertyInfo;
+            return true;
+        }
+
+        // Other possible expression bodies here
+        return false;
+    }
+
+    public DataTable Build(IEnumerable<T> source)
+    {
+        ArgumentNullException.ThrowIfNull(source);
+
+        var table = new DataTable();
+
+        foreach (var (name, (type, _)) in _columnBuilders)
+        {
+            table.Columns.Add(new DataColumn(name, type));
+        }
+
+        foreach (var entity in source)
+        {
+            var row = table.NewRow();
+
+            foreach (var (name, (_, getter)) in _columnBuilders)
+            {
+                var value = getter(entity);
+                if (value is null)
+                {
+                    row[name] = DBNull.Value;
+                }
+                else
+                {
+                    row[name] = value;
+                }
+            }
+
+            table.Rows.Add(row);
+        }
+
+        return table;
+    }
+}
+
 public static class DapperHelpers
 {
+    private static readonly DataTableBuilder<OrganizationSponsorship> _organizationSponsorshipTableBuilder = new(
+        [
+            os => os.Id,
+            os => os.SponsoringOrganizationId,
+            os => os.SponsoringOrganizationUserId,
+            os => os.SponsoredOrganizationId,
+            os => os.FriendlyName,
+            os => os.OfferedToEmail,
+            os => os.PlanSponsorshipType,
+            os => os.LastSyncDate,
+            os => os.ValidUntil,
+            os => os.ToDelete,
+        ]
+    );
+
     public static DataTable ToGuidIdArrayTVP(this IEnumerable<Guid> ids)
     {
         return ids.ToArrayTVP("GuidId");
@@ -63,24 +207,9 @@ public static class DapperHelpers
 
     public static DataTable ToTvp(this IEnumerable<OrganizationSponsorship> organizationSponsorships)
     {
-        var table = new DataTable();
+        var table = _organizationSponsorshipTableBuilder.Build(organizationSponsorships ?? []);
         table.SetTypeName("[dbo].[OrganizationSponsorshipType]");
-
-        var columnData = new List<(string name, Type type, Func<OrganizationSponsorship, object?> getter)>
-        {
-            (nameof(OrganizationSponsorship.Id), typeof(Guid), ou => ou.Id),
-            (nameof(OrganizationSponsorship.SponsoringOrganizationId), typeof(Guid), ou => ou.SponsoringOrganizationId),
-            (nameof(OrganizationSponsorship.SponsoringOrganizationUserId), typeof(Guid), ou => ou.SponsoringOrganizationUserId),
-            (nameof(OrganizationSponsorship.SponsoredOrganizationId), typeof(Guid), ou => ou.SponsoredOrganizationId),
-            (nameof(OrganizationSponsorship.FriendlyName), typeof(string), ou => ou.FriendlyName),
-            (nameof(OrganizationSponsorship.OfferedToEmail), typeof(string), ou => ou.OfferedToEmail),
-            (nameof(OrganizationSponsorship.PlanSponsorshipType), typeof(byte), ou => ou.PlanSponsorshipType),
-            (nameof(OrganizationSponsorship.LastSyncDate), typeof(DateTime), ou => ou.LastSyncDate),
-            (nameof(OrganizationSponsorship.ValidUntil), typeof(DateTime), ou => ou.ValidUntil),
-            (nameof(OrganizationSponsorship.ToDelete), typeof(bool), ou => ou.ToDelete),
-        };
-
-        return organizationSponsorships.BuildTable(table, columnData);
+        return table;
     }
 
     public static DataTable BuildTable<T>(this IEnumerable<T> entities, DataTable table,