Json reader.

src/Squidex.Infrastructure/Json/Newtonsoft/JsonClassConverter.cs

@@ -13,7 +13,7 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 {
     public abstract class JsonClassConverter<T> : JsonConverter, ISupportedTypes where T : class
     {
-        public IEnumerable<Type> SupportedTypes
+        public virtual IEnumerable<Type> SupportedTypes
         {
             get { yield return typeof(T); }
         }

src/Squidex.Infrastructure/Json/Newtonsoft/LanguageConverter.cs

@@ -19,12 +19,9 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 
         protected override Language ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
         {
-            if (reader.TokenType != JsonToken.String)
-            {
-                throw new JsonException($"Expected String, but got {reader.TokenType}.");
-            }
+            var value = serializer.Deserialize<string>(reader);
 
-            return Language.GetLanguage(reader.Value.ToString());
+            return Language.GetLanguage(value);
         }
     }
 }

src/Squidex.Infrastructure/Json/Newtonsoft/NamedGuidIdConverter.cs

@@ -19,12 +19,9 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 
         protected override NamedId<Guid> ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
         {
-            if (reader.TokenType != JsonToken.String)
-            {
-                throw new JsonException($"Expected String, but got {reader.TokenType}.");
-            }
+            var value = serializer.Deserialize<string>(reader);
 
-            if (!NamedId<Guid>.TryParse(reader.Value.ToString(), Guid.TryParse, out var result))
+            if (!NamedId<Guid>.TryParse(value, Guid.TryParse, out var result))
             {
                 throw new JsonException("Named id must have more than 2 parts divided by commata.");
             }

src/Squidex.Infrastructure/Json/Newtonsoft/NamedLongIdConverter.cs

@@ -19,12 +19,9 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 
         protected override NamedId<long> ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
         {
-            if (reader.TokenType != JsonToken.String)
-            {
-                throw new JsonException($"Expected String, but got {reader.TokenType}.");
-            }
+            var value = serializer.Deserialize<string>(reader);
 
-            if (!NamedId<long>.TryParse(reader.Value.ToString(), long.TryParse, out var result))
+            if (!NamedId<long>.TryParse(value, long.TryParse, out var result))
             {
                 throw new JsonException("Named id must have at least 2 parts divided by commata.");
             }

src/Squidex.Infrastructure/Json/Newtonsoft/NamedStringIdConverter.cs

@@ -19,12 +19,9 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 
         protected override NamedId<string> ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
         {
-            if (reader.TokenType != JsonToken.String)
-            {
-                throw new JsonException($"Expected String, but got {reader.TokenType}.");
-            }
+            var value = serializer.Deserialize<string>(reader);
 
-            if (!NamedId<string>.TryParse(reader.Value.ToString(), ParseString, out var result))
+            if (!NamedId<string>.TryParse(value, ParseString, out var result))
             {
                 throw new JsonException("Named id must have at least 2 parts divided by commata.");
             }

src/Squidex.Infrastructure/Json/Newtonsoft/RefTokenConverter.cs

@@ -19,12 +19,9 @@ namespace Squidex.Infrastructure.Json.Newtonsoft
 
         protected override RefToken ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
         {
-            if (reader.TokenType != JsonToken.String)
-            {
-                throw new JsonException($"Expected String, but got {reader.TokenType}.");
-            }
+            var value = serializer.Deserialize<string>(reader);
 
-            if (!RefToken.TryParse(reader.Value.ToString(), out var result))
+            if (!RefToken.TryParse(value, out var result))
             {
                 throw new JsonException("Named id must have at least 2 parts divided by colon.");
             }

src/Squidex.Infrastructure/Queries/Json/FilterConverter.cs

@@ -0,0 +1,162 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Newtonsoft.Json;
+using Squidex.Infrastructure.Json.Newtonsoft;
+using Squidex.Infrastructure.Json.Objects;
+
+namespace Squidex.Infrastructure.Queries.Json
+{
+    public sealed class FilterConverter : JsonClassConverter<FilterNode<IJsonValue>>
+    {
+        public override IEnumerable<Type> SupportedTypes
+        {
+            get
+            {
+                yield return typeof(CompareFilter<IJsonValue>);
+                yield return typeof(FilterNode<IJsonValue>);
+                yield return typeof(LogicalFilter<IJsonValue>);
+                yield return typeof(NegateFilter<IJsonValue>);
+            }
+        }
+
+        public override bool CanConvert(Type objectType)
+        {
+            return SupportedTypes.Contains(objectType);
+        }
+
+        protected override FilterNode<IJsonValue> ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
+        {
+            if (reader.TokenType != JsonToken.StartObject)
+            {
+                throw new JsonException($"Expected StartObject, but got {reader.TokenType}.");
+            }
+
+            FilterNode<IJsonValue> result = null;
+
+            var comparePath = (PropertyPath)null;
+            var compareOperator = (CompareOperator)99;
+            var compareValue = (IJsonValue)null;
+
+            while (reader.Read())
+            {
+                switch (reader.TokenType)
+                {
+                    case JsonToken.PropertyName:
+                        string propertyName = reader.Value.ToString();
+
+                        if (!reader.Read())
+                        {
+                            throw new JsonSerializationException("Unexpected end when reading filter.");
+                        }
+
+                        if (result != null)
+                        {
+                            throw new JsonSerializationException($"Unexpected property {propertyName}");
+                        }
+
+                        switch (propertyName.ToLowerInvariant())
+                        {
+                            case "not":
+                                var filter = serializer.Deserialize<FilterNode<IJsonValue>>(reader);
+
+                                result = new NegateFilter<IJsonValue>(filter);
+                                break;
+                            case "and":
+                                var andFilters = serializer.Deserialize<List<FilterNode<IJsonValue>>>(reader);
+
+                                result = new LogicalFilter<IJsonValue>(LogicalFilterType.And, andFilters);
+                                break;
+                            case "or":
+                                var orFilters = serializer.Deserialize<List<FilterNode<IJsonValue>>>(reader);
+
+                                result = new LogicalFilter<IJsonValue>(LogicalFilterType.Or, orFilters);
+                                break;
+                            case "path":
+                                comparePath = serializer.Deserialize<PropertyPath>(reader);
+                                break;
+                            case "op":
+                                compareOperator = ReadOperator(reader, serializer);
+                                break;
+                            case "value":
+                                compareValue = serializer.Deserialize<IJsonValue>(reader);
+                                break;
+                        }
+
+                        break;
+                    case JsonToken.Comment:
+                        break;
+                    case JsonToken.EndObject:
+                        if (result != null)
+                        {
+                            return result;
+                        }
+
+                        if (comparePath == null)
+                        {
+                            throw new JsonSerializationException("Path not defined.");
+                        }
+
+                        if (compareValue == null && compareOperator != CompareOperator.Empty)
+                        {
+                            throw new JsonSerializationException("Value not defined.");
+                        }
+
+                        if (!compareOperator.IsEnumValue())
+                        {
+                            throw new JsonSerializationException("Operator not defined.");
+                        }
+
+                        return new CompareFilter<IJsonValue>(comparePath, compareOperator, compareValue ?? JsonValue.Null);
+                }
+            }
+
+            throw new JsonSerializationException("Unexpected end when reading filter.");
+        }
+
+        private static CompareOperator ReadOperator(JsonReader reader, JsonSerializer serializer)
+        {
+            var value = serializer.Deserialize<string>(reader);
+
+            switch (value.ToLowerInvariant())
+            {
+                case "eq":
+                    return CompareOperator.Equals;
+                case "ne":
+                    return CompareOperator.NotEquals;
+                case "lt":
+                    return CompareOperator.LessThan;
+                case "le":
+                    return CompareOperator.LessThanOrEqual;
+                case "gt":
+                    return CompareOperator.GreaterThan;
+                case "ge":
+                    return CompareOperator.GreaterThanOrEqual;
+                case "empty":
+                    return CompareOperator.Empty;
+                case "contains":
+                    return CompareOperator.Contains;
+                case "endswith":
+                    return CompareOperator.EndsWith;
+                case "startswith":
+                    return CompareOperator.StartsWith;
+                case "in":
+                    return CompareOperator.In;
+            }
+
+            throw new JsonSerializationException($"Unexpected compare operator, got {value}.");
+        }
+
+        protected override void WriteValue(JsonWriter writer, FilterNode<IJsonValue> value, JsonSerializer serializer)
+        {
+            throw new NotSupportedException();
+        }
+    }
+}

src/Squidex.Infrastructure/Queries/Json/PropertyPathConverter.cs

@@ -0,0 +1,29 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using System;
+using System.Collections.Generic;
+using Newtonsoft.Json;
+using Squidex.Infrastructure.Json.Newtonsoft;
+
+namespace Squidex.Infrastructure.Queries.Json
+{
+    public sealed class PropertyPathConverter : JsonClassConverter<PropertyPath>
+    {
+        protected override PropertyPath ReadValue(JsonReader reader, Type objectType, JsonSerializer serializer)
+        {
+            var value = serializer.Deserialize<string>(reader);
+
+            return value;
+        }
+
+        protected override void WriteValue(JsonWriter writer, PropertyPath value, JsonSerializer serializer)
+        {
+            serializer.Serialize(writer, (IEnumerable<string>)value);
+        }
+    }
+}

src/Squidex.Infrastructure/Queries/PropertyPath.cs

@@ -15,6 +15,8 @@ namespace Squidex.Infrastructure.Queries
 {
     public sealed class PropertyPath : ReadOnlyCollection<string>
     {
+        private static readonly char[] Separators = { '.', '/' };
+
         public PropertyPath(IList<string> items)
             : base(items)
         {
@@ -26,7 +28,7 @@ namespace Squidex.Infrastructure.Queries
 
         public static implicit operator PropertyPath(string path)
         {
-            return new PropertyPath(path?.Split('.', '/')?.ToList());
+            return new PropertyPath(path?.Split(Separators, StringSplitOptions.RemoveEmptyEntries)?.ToList());
         }
 
         public static implicit operator PropertyPath(string[] path)

tests/Squidex.Infrastructure.Tests/Queries/QueryJsonTests.cs

@@ -0,0 +1,181 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using Newtonsoft.Json;
+using Squidex.Infrastructure.Json.Objects;
+using Squidex.Infrastructure.TestHelpers;
+using Xunit;
+
+namespace Squidex.Infrastructure.Queries
+{
+    public class QueryJsonTests
+    {
+        [Theory]
+        [InlineData("eq", "property == 12")]
+        [InlineData("ne", "property != 12")]
+        [InlineData("le", "property <= 12")]
+        [InlineData("lt", "property < 12")]
+        [InlineData("ge", "property >= 12")]
+        [InlineData("gt", "property > 12")]
+        [InlineData("contains", "contains(property, 12)")]
+        [InlineData("endswith", "endsWith(property, 12)")]
+        [InlineData("startswith", "startsWith(property, 12)")]
+        public void Should_convert_comparison(string op, string expected)
+        {
+            var json = new
+            {
+                path = "property",
+                op,
+                value = 12
+            };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal(expected, filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_comparison_empty()
+        {
+            var json = new { path = "property", op = "empty" };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("empty(property)", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_comparison_in()
+        {
+            var json = new { path = "property", op = "in", value = new[] { 12, 13 } };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("property in [12, 13]", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_comparison_with_deep_path()
+        {
+            var json = new { path = "property.nested", op = "eq", value = 12 };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("property.nested == 12", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_logical_and()
+        {
+            var json = new
+            {
+                and = new[]
+                {
+                    new { path = "property", op = "ge", value = 10 },
+                    new { path = "property", op = "lt", value = 20 }
+                }
+            };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("(property >= 10 && property < 20)", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_logical_or()
+        {
+            var json = new
+            {
+                or = new[]
+                {
+                    new { path = "property", op = "ge", value = 10 },
+                    new { path = "property", op = "lt", value = 20 }
+                }
+            };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("(property >= 10 || property < 20)", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_convert_logical_not()
+        {
+            var json = new
+            {
+                not = new { path = "property", op = "ge", value = 10 }
+            };
+
+            var filter = SerializeAndDeserialize(json);
+
+            Assert.Equal("!(property >= 10)", filter.ToString());
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_invalid_operator()
+        {
+            var json = new { path = "property", op = "invalid", value = 12 };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_missing_path()
+        {
+            var json = new { op = "invalid", value = 12 };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_missing_operator()
+        {
+            var json = new { path = "property", value = 12 };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_missing_value()
+        {
+            var json = new { path = "property", op = "invalid" };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_invalid_property()
+        {
+            var json = new { path = "property", op = "invalid", value = 12, other = 4 };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        [Fact]
+        public void Should_throw_exception_for_invalid_property_after_filter()
+        {
+            var json = new
+            {
+                and = new[]
+                {
+                    new { path = "property", op = "ge", value = 10 },
+                    new { path = "property", op = "lt", value = 20 }
+                },
+                additional = 1
+            };
+
+            Assert.ThrowsAny<JsonException>(() => SerializeAndDeserialize(json));
+        }
+
+        private static FilterNode<IJsonValue> SerializeAndDeserialize<T>(T value)
+        {
+            var json = JsonHelper.DefaultSerializer.Serialize(value, true);
+
+            return JsonHelper.DefaultSerializer.Deserialize<FilterNode<IJsonValue>>(json);
+        }
+    }
+}

tests/Squidex.Infrastructure.Tests/Queries/ODataConversionTests.cs → tests/Squidex.Infrastructure.Tests/Queries/QueryODataConversionTests.cs

@@ -11,11 +11,11 @@ using Xunit;
 
 namespace Squidex.Infrastructure.Queries
 {
-    public class ODataConversionTests
+    public class QueryODataConversionTests
     {
         private static readonly IEdmModel EdmModel;
 
-        static ODataConversionTests()
+        static QueryODataConversionTests()
         {
             var entityType = new EdmEntityType("Squidex", "Users");
 

tests/Squidex.Infrastructure.Tests/TestHelpers/JsonHelper.cs

@@ -10,6 +10,7 @@ using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
 using Squidex.Infrastructure.Json;
 using Squidex.Infrastructure.Json.Newtonsoft;
+using Squidex.Infrastructure.Queries.Json;
 
 namespace Squidex.Infrastructure.TestHelpers
 {
@@ -34,11 +35,13 @@ namespace Squidex.Infrastructure.TestHelpers
                     new ClaimsPrincipalConverter(),
                     new InstantConverter(),
                     new EnvelopeHeadersConverter(),
+                    new FilterConverter(),
                     new JsonValueConverter(),
                     new LanguageConverter(),
                     new NamedGuidIdConverter(),
                     new NamedLongIdConverter(),
                     new NamedStringIdConverter(),
+                    new PropertyPathConverter(),
                     new RefTokenConverter(),
                     new StringEnumConverter()),