Fixed json object support (#606)

Author: DarkWanderer

ClickHouse.Client.Tests/BulkCopy/BulkCopyTests.cs

@@ -470,5 +470,31 @@ public async Task ShouldNotAffectSharedArrayPool()
         Assert.DoesNotThrow(() => { rentedArray[0] = 1; });
         ArrayPool<object>.Shared.Return(rentedArray);
     }
+
+    [Test]
+    [RequiredFeature(Feature.Json)]
+    public async Task ShouldInsertJson()
+    {
+        var targetTable = "test." + SanitizeTableName($"bulk_json");
+        await connection.ExecuteStatementAsync($"DROP TABLE IF EXISTS {targetTable}");
+        await connection.ExecuteStatementAsync($"CREATE TABLE IF NOT EXISTS {targetTable} (value JSON) ENGINE Memory");
+
+        using var bulkCopy = new ClickHouseBulkCopy(connection)
+        {
+            DestinationTableName = targetTable,
+        };
+
+        var jsonString = "{\"string\": \"value\"}";
+        var jsonObject = (JsonObject)JsonNode.Parse(jsonString);
+
+        await bulkCopy.InitAsync();
+        await bulkCopy.WriteToServerAsync([[jsonString], [jsonObject]]);
+
+        using var reader = await connection.ExecuteReaderAsync($"SELECT * from {targetTable}");
+        while(reader.Read())
+        {
+            Assert.That(reader.GetValue(0), Is.EqualTo(jsonObject).UsingPropertiesComparer());
+        }
+    }
 }
 

ClickHouse.Client.Tests/TestUtilities.cs

@@ -249,7 +249,7 @@ public static IEnumerable<DataTypeSample> GetDataTypeSamples()
                 "{\"val\": 1.5}",
                 "{\"val\": [1,2]}",
                 "{ \"nested\": { \"double\": 1.23456, \"int\": 123456, \"string\": \"stringValue\" } }",
-                //"{ \"nested1\": { \"nested2\": {\"nested3\": {\"a\": 1, \"b\": \"c\", \"d\": null}} } }",
+                "{ \"nestedArray\": [{\"val\": 1}, {\"val\": 2}] }",
             };
 
             foreach (var example in jsonExamples)

ClickHouse.Client/ADO/Readers/ClickHouseDataReader.cs

@@ -135,7 +135,7 @@ public override int GetOrdinal(string name)
         return index;
     }
 
-    public override string GetString(int ordinal) => (string)GetValue(ordinal);
+    public override string GetString(int ordinal) => GetValue(ordinal)?.ToString();
 
     public override object GetValue(int ordinal) => CurrentRow[ordinal];
 

ClickHouse.Client/Types/JsonType.cs

@@ -64,6 +64,11 @@ public override void Write(ExtendedBinaryWriter writer, object value)
 
 
         // Simple depth-first search to flatten the JSON object into a dictionary
+        WriteJsonObject(writer, rootObject);
+    }
+
+    internal static void WriteJsonObject(ExtendedBinaryWriter writer, JsonObject rootObject)
+    {
         Dictionary<string, JsonNode> fields = new();
         StringBuilder currentPath = new();
         FlattenJson(rootObject, ref currentPath, ref fields);
@@ -191,6 +196,12 @@ internal static void WriteJsonArray(ExtendedBinaryWriter writer, JsonArray array
             case JsonValueKind.Null:
                 writer.Write((byte)0x00);
                 break;
+            case JsonValueKind.Object:
+                writer.Write((byte)0x30);
+                writer.Write((byte)0);
+                writer.Write7BitEncodedInt(256);
+                writer.Write((int)16);
+                break;
             default:
                 throw new SerializationException($"Unsupported JSON value kind: {kind}");
         }
@@ -222,6 +233,9 @@ internal static void WriteJsonArray(ExtendedBinaryWriter writer, JsonArray array
                 case JsonValueKind.Null:
                     writer.Write((byte)0x00);
                     break;
+                case JsonValueKind.Object:
+                    WriteJsonObject(writer, (JsonObject)value);
+                    break;
                 default:
                     throw new SerializationException($"Unsupported JSON value kind: {value.GetValueKind()}");
             }

ClickHouse.Client/Types/TypeConverter.cs

@@ -342,10 +342,15 @@ internal static ClickHouseType FromByteCode(ExtendedBinaryReader reader)
             case 0x2D: return new BooleanType();
             // case 0x2E: return new SimpleAggregateFunctionType(); // TODO function
             // case 0x2F: return new NestedType(); // TODO nested types
-            case 0x30: return new JsonType(); // TODO JSON settings
+            case 0x30:
+                var _serializationVersion = reader.ReadByte(); // <uint8_serialization_version>
+                var _maxDynamicPaths = reader.Read7BitEncodedInt(); // <var_int_max_dynamic_paths>
+                var _maxDynamicTypes = reader.ReadInt32(); // <uint8_max_dynamic_types>
+                return new JsonType(); // TODO JSON settings
             default:
                 break;
-        };
+        }
+        ;
         throw new ArgumentOutOfRangeException(nameof(value), $"Unknown type: {value}");
     }
 }