Replace with Swagger filter

src/Api/SecretsManager/Models/Response/BaseSecretResponseModel.cs

@@ -1,6 +1,5 @@
 #nullable enable
 
-using System.ComponentModel.DataAnnotations;
 using Bit.Core.Models.Api;
 using Bit.Core.SecretsManager.Entities;
 
@@ -27,10 +26,8 @@ public BaseSecretResponseModel(Secret secret, string objectName = _objectName) :
         Projects = secret.Projects?.Select(p => new SecretResponseInnerProject(p));
     }
 
-    [Required]
     public Guid Id { get; }
 
-    [Required]
     public Guid OrganizationId { get; }
 
     public string? Key { get; }
@@ -39,10 +36,8 @@ public BaseSecretResponseModel(Secret secret, string objectName = _objectName) :
 
     public string? Note { get; }
 
-    [Required]
     public DateTime CreationDate { get; }
 
-    [Required]
     public DateTime RevisionDate { get; }
 
     public IEnumerable<SecretResponseInnerProject>? Projects { get; init; }

src/Api/Utilities/ServiceCollectionExtensions.cs

@@ -71,6 +71,7 @@ public static void AddSwagger(this IServiceCollection services, GlobalSettings g
             // config.UseReferencedDefinitionsForEnums();
 
             config.SchemaFilter<EnumSchemaFilter>();
+            config.SchemaFilter<RequireNotNullableSchemaFilter>();
 
             var apiFilePath = Path.Combine(AppContext.BaseDirectory, "Api.xml");
             config.IncludeXmlComments(apiFilePath, true);

src/SharedWeb/Swagger/RequireNotNullableSchemaFilter.cs

@@ -0,0 +1,66 @@
+using System.Reflection;
+using Microsoft.OpenApi.Models;
+using Swashbuckle.AspNetCore.SwaggerGen;
+
+namespace Bit.SharedWeb.Swagger;
+
+/// <summary>
+///
+/// </summary>
+/// <remarks>
+/// Credits: https://github.com/domaindrivendev/Swashbuckle.AspNetCore/issues/2036#issuecomment-894015122
+/// </remarks>
+public class RequireNotNullableSchemaFilter : ISchemaFilter
+{
+    public void Apply(OpenApiSchema schema, SchemaFilterContext context)
+    {
+        if (schema.Properties == null)
+        {
+            return;
+        }
+
+        FixNullableProperties(schema, context);
+
+        var notNullableProperties = schema
+            .Properties
+            .Where(x => !x.Value.Nullable && x.Value.Default == default && !schema.Required.Contains(x.Key))
+            .ToList();
+
+        foreach (var property in notNullableProperties)
+        {
+            schema.Required.Add(property.Key);
+        }
+    }
+
+    /// <summary>
+    /// Option "SupportNonNullableReferenceTypes" not working with complex types ({ "type": "object" }),
+    /// so they always have "Nullable = false",
+    /// see method "SchemaGenerator.GenerateSchemaForMember"
+    /// </summary>
+    private static void FixNullableProperties(OpenApiSchema schema, SchemaFilterContext context)
+    {
+        foreach (var property in schema.Properties)
+        {
+            var field = context.Type
+                .GetMembers(BindingFlags.Public | BindingFlags.Instance)
+                .FirstOrDefault(x =>
+                    string.Equals(x.Name, property.Key, StringComparison.InvariantCultureIgnoreCase));
+
+            if (field == null)
+            {
+                continue;
+            }
+
+            var fieldType = field switch
+            {
+                FieldInfo fieldInfo => fieldInfo.FieldType,
+                PropertyInfo propertyInfo => propertyInfo.PropertyType,
+                _ => throw new NotSupportedException(),
+            };
+
+            property.Value.Nullable = fieldType.IsValueType
+                ? Nullable.GetUnderlyingType(fieldType) != null
+                : !field.IsNonNullableReferenceType();
+        }
+    }
+}