Default DateTimeKind configuration

docs/pages/guide/gridifyGlobalConfiguration.md

@@ -47,6 +47,13 @@ some ORMs like NHibernate don't support this. You can disable this behavior by s
 - type: `bool`
 - default: `false`
 
+### DefaultDateTimeKind
+
+By default, Gridify uses the `DateTimeKind.Unspecified` when parsing dates. You can change this behavior by setting this property to `DateTimeKind.Utc` or `DateTimeKind.Local`. This option is useful when you want to use Gridify with a database that requires a specific `DateTimeKind`, for example when using npgsql and postgresql. 
+
+- type: `DateTimeKind`
+- default: `null`
+
 ## CustomOperators
 
 Using the `Register` method of this property you can add your own custom operators.

docs/pages/guide/gridifyMapper.md

@@ -144,6 +144,17 @@ By setting this to `false`, Gridify don't allow searching on null values using t
 var mapper = new GridifyMapper<Person>(q => q.AllowNullSearch = false);
 ```
 
+### DefaultDateTimeKind
+
+By setting this property to a `DateTimeKind` value, you can change the default `DateTimeKind` used when parsing dates.
+
+- type: `DateTimeKind`
+- default: `null`
+
+``` csharp
+var mapper = new GridifyMapper<Person>(q => q.DefaultDateTimeKind = DateTimeKind.Utc);
+```
+
 ## Filtering on Nested Collections
 
 You can use LINQ `Select` and `SelectMany` methods to filter your data using its nested collections.

src/Gridify/Builder/BaseQueryBuilder.cs

@@ -198,6 +198,14 @@ private static object AddIndexerNullCheck(IGMap<T> gMap, object query)
             {
                return BuildAlwaysFalseQuery(parameter);
             }
+
+         if (value is DateTime dateTime)
+         {
+            if (mapper.Configuration.DefaultDateTimeKind.HasValue)
+            {
+               value = DateTime.SpecifyKind(dateTime, mapper.Configuration.DefaultDateTimeKind.Value);
+            }
+         }
       }
 
       // handle case-Insensitive search

src/Gridify/GridifyGlobalConfiguration.cs

@@ -46,6 +46,13 @@ public static class GridifyGlobalConfiguration
       /// Default is false
       /// </summary>
       public static bool DisableNullChecks { get; set; } = false;
+
+      /// <summary>
+      /// By default, DateTimeKind.Unspecified is used.
+      /// You can change this behavior by setting this property to a DateTimeKind value.
+      /// Default is null
+      /// </summary>
+      public static DateTimeKind? DefaultDateTimeKind { get; set; } = null;
 
       /// <summary>
       /// Specifies how field names are inferred from CLR property names.

src/Gridify/GridifyMapperConfiguration.cs

@@ -23,6 +23,13 @@ public record GridifyMapperConfiguration
    /// Default is false
    /// </summary>
    public bool IgnoreNotMappedFields { get; set; } = GridifyGlobalConfiguration.IgnoreNotMappedFields;
+
+   /// <summary>
+   /// By default, DateTimeKind.Unspecified is used.
+   /// You can change this behavior by setting this property to a DateTimeKind value.
+   /// Default is null
+   /// </summary>
+   public DateTimeKind? DefaultDateTimeKind { get; set; } = GridifyGlobalConfiguration.DefaultDateTimeKind;
 
    /// <summary>
    /// Specifies how field names are inferred from CLR property names.

test/EntityFrameworkPostgreSqlIntegrationTests/Issue188Tests.cs

@@ -0,0 +1,30 @@
+using EntityFrameworkIntegrationTests.cs;
+using Microsoft.EntityFrameworkCore;
+using Xunit;
+
+namespace Gridify.Tests;
+
+public class Issue188Tests
+{
+
+   private readonly MyDbContext _dbContext = new();
+
+   [Fact]
+   public void DateTimeFilteringWithUTCKind_UsingGridifyMapper_ShouldNotThrowException()
+   {
+      var mapper = new GridifyMapper<User>(q => q.DefaultDateTimeKind = DateTimeKind.Utc)
+         .GenerateMappings();
+      _dbContext.Users.ApplyFiltering("CreateDate>2023-11-14", mapper).ToQueryString();
+   }
+
+   [Fact]
+   public void DateTimeFilteringWithUTCKind_UsingGlobalConfiguration_ShouldNotThrowException()
+   {
+      GridifyGlobalConfiguration.DefaultDateTimeKind = DateTimeKind.Utc;
+      _dbContext.Users.ApplyFiltering("CreateDate>2023-11-14").ToQueryString();
+      GridifyGlobalConfiguration.DefaultDateTimeKind = null;
+   }
+
+}
+
+