fix

Author: eocron

Eocron.Algorithms.Tests/PagingQueryableTests.cs

@@ -16,25 +16,24 @@ public class PagingQueryableTests
         public void Setup()
         {
             var now = new DateTime(2017, 12, 1);
-            _items = new List<TestDbEntity>()
-            {
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000001"),Name = "Test1", Modified = now.AddDays(1)},
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000002"),Name = "Test2", Modified = now.AddDays(2)},
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000003"),Name = "Test3", Modified = now.AddDays(3)},
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000004"),Name = "Test4", Modified = now.AddDays(4)},
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000005"),Name = "Test5", Modified = now.AddDays(5)},
-                new TestDbEntity(){Id = Guid.Parse("10000000-0000-0000-0000-000000000006"),Name = "Test6", Modified = now.AddDays(6)},
-            };
+            _items = [
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000001"),Name = "Test1", Modified = now.AddDays(1)},
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000002"),Name = "Test2", Modified = now.AddDays(2)},
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000003"),Name = "Test3", Modified = now.AddDays(3)},
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000004"),Name = "Test4", Modified = now.AddDays(4)},
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000005"),Name = "Test5", Modified = now.AddDays(5)},
+                new(){Id = Guid.Parse("10000000-0000-0000-0000-000000000006"),Name = "Test6", Modified = now.AddDays(6)},
+            ];
         }
 
         [Test]
         public void SanityCheck()
         {
             var queryable = _items.AsQueryable();
 
-            var cfg = new PagingConfiguration<TestDbEntity>();
-            cfg.AddKeySelector(x=> x.Modified, isDescending: true);
-            cfg.AddKeySelector(x=> x.Id);
+            var cfg = new PagingConfiguration<TestDbEntity>()
+                .OrderByDescending(x => x.Modified)
+                .OrderBy(x => x.Id);
 
             var result = new List<TestDbEntity>();
             var queries = new List<string>();
@@ -66,8 +65,8 @@ public void SanityCheck()
                 "System.Collections.Generic.List`1[Eocron.Algorithms.Tests.PagingQueryableTests+TestDbEntity].OrderByDescending(x => x.Modified).ThenBy(x => x.Id).Where(x => (((x.Modified == 12/2/2017 12:00:00 AM) AndAlso (x.Id > 10000000-0000-0000-0000-000000000001)) OrElse (x.Modified < 12/2/2017 12:00:00 AM)))"
             ]);
         }
-        
-        public class TestDbEntity
+
+        private class TestDbEntity
         {
             public Guid Id { get; set; }
 

Eocron.Algorithms/Queryable/Paging/IPagingConfiguration.cs

@@ -0,0 +1,11 @@
+using System;
+using System.Linq.Expressions;
+
+namespace Eocron.Algorithms.Queryable.Paging
+{
+    public interface IPagingConfiguration<TEntity>
+    {
+        void AddKeySelector<TKey>(Expression<Func<TEntity, TKey>> keySelector, bool isDescending = false);
+        string GetContinuationToken(TEntity entity);
+    }
+}

Eocron.Algorithms/Queryable/Paging/PagingConfiguration.cs

@@ -6,13 +6,12 @@
 
 namespace Eocron.Algorithms.Queryable.Paging
 {
-    public sealed class PagingConfiguration<TEntity>
+    public sealed class PagingConfiguration<TEntity> : IPagingConfiguration<TEntity>
     {
         private readonly List<PagingKeyConfiguration> _keys = new();
 
-        public ParameterExpression Input = Expression.Parameter(typeof(TEntity), "x");
-        
-        public IReadOnlyList<PagingKeyConfiguration> Keys => _keys;
+        internal ParameterExpression Input = Expression.Parameter(typeof(TEntity), "x");
+        internal IReadOnlyList<PagingKeyConfiguration> Keys => _keys;
 
         private static readonly JsonSerializerSettings JsonSerializerSettings = new JsonSerializerSettings()
         {
@@ -45,7 +44,7 @@ public string GetContinuationToken(TEntity entity)
                 JsonSerializerSettings);
         }
 
-        public List<object> GetKeyValues(string continuationToken)
+        internal List<object> GetKeyValues(string continuationToken)
         {
             if (string.IsNullOrWhiteSpace(continuationToken))
                 throw new ArgumentNullException(nameof(continuationToken));

Eocron.Algorithms/Queryable/Paging/PagingQueryableExtensions.cs

@@ -9,6 +9,19 @@ namespace Eocron.Algorithms.Queryable.Paging
     /// </summary>
     public static class PagingQueryableExtensions
     {
+        public static PagingConfiguration<TEntity> OrderBy<TEntity, TKey>(this PagingConfiguration<TEntity> configuration,
+            Expression<Func<TEntity, TKey>> orderByExpression)
+        {
+            configuration.AddKeySelector(orderByExpression);
+            return configuration;
+        }
+        
+        public static PagingConfiguration<TEntity> OrderByDescending<TEntity, TKey>(this PagingConfiguration<TEntity> configuration,
+            Expression<Func<TEntity, TKey>> orderByExpression)
+        {
+            configuration.AddKeySelector(orderByExpression, isDescending: true);
+            return configuration;
+        }
         /// <summary>
         /// Applies configured ordering.
         /// Applies skipping WHERE condition to IQueryable if continuation token is not empty.