Repository: provectus/kafka-ui
Issue: Fields with logical type as decimal displays unicode values instead of original numeric values.
Labels: type/bug
scope/backend
status/accepted
status/confirmed
area/serde

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**Describe the bug**
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Fields with logical type as decimal are not showing correct numeric values from topics with schema registry. details for fields display value and schema registry definition is given below in addl context.

**Set up**
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11.15.2022 07:05:35
(
[5900f8e](https://github.com/provectus/kafka-ui/commit/5900f8e)
)

**Steps to Reproduce**
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1. 

**Expected behavior**
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Data | SchemaRegistry
-- | --
"field1":   {      "bytes":   "#òoÁ\u0000\u0000"     }, | {           "name":   "field1",           "type": [            "null",            {             "type":   "bytes",             "logicalType":   "decimal",             "precision":   24,             "scale": 16            }           ],           "doc": "this is   field1.",           "default": null          },
"field2":   {      "bytes":   "#òoÁ\u0000\u0000"     }, | {           "name":   "field2",           "type": [            "null",            {             "type":   "bytes",             "logicalType":   "decimal",             "precision":   24,             "scale": 16            }           ],           "doc": "this is   field2.",           "default": null          },
"field3":   {      "string":   "L"     }, |  
"field4":   {      "string":   "0"     }, |  
"field5":   {      "boolean": false     }, |  
"field6":   {      "com.avro.schema.common.BigAmount_30_10":   {       "amount":   "\u000e3â\"\u0000",       "currency":   "USD"      }     }, | {           "name":   "field6",           "type": [            "null",            {             "type":   "record",             "name":   "BigAmount_30_10",             "namespace":   "com.avro.schema.common",             "fields": [              {               "name":   "amount",               "type": {                "type": "bytes",                "logicalType":   "decimal",                "precision":   30,                "scale":   10               }              },              {               "name":   "currency",               "type": {                "type":   "string",                  "avro.java.string": "String"               }              }             ]            }           ],           "doc": "this is   field6.",           "default": null          },
"field7":   {      "com.avro.schema.common.BigAmount_20_8":   {       "amount":   "$[Ü",       "currency":   "USD"      }     }, | {           "name":   "field7",           "type": [            "null",            {             "type":   "record",             "name":   "BigAmount_20_8",             "namespace":   "com.avro.schema.common",             "fields": [              {               "name":   "amount",               "type": {                "type": "bytes",                "logicalType":   "decimal",                "precision":   20,                "scale": 8               }              },              {               "name":   "currency",               "type": {                "type":   "string",                  "avro.java.string": "String"               }              }             ]            }           ],           "doc": "this is   field7.",           "default": null          },
"field8":   {      "com.avro.schema.common.BigAmount_30_10":   {       "amount":   "\u000e3â\"\u0000",       "currency":   "USD"      }     }, | {           "name":   "field8",           "type": [            "null",              "com.avro.schema.common.BigAmount_30_10"           ],           "doc": "this is   field8.",           "default": null          },



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Issue comments:
Thanks for raising an issue
You are missing config setting on the kafka avro deserializer. 

Specifically AVRO_USE_LOGICAL_TYPE_CONVERTERS_CONFIG should be set to true

 `  
 protected void configure(KafkaAvroDeserializerConfig config) {
    configureClientProperties(config, new AvroSchemaProvider());
    useSpecificAvroReader = config
        .getBoolean(KafkaAvroDeserializerConfig.SPECIFIC_AVRO_READER_CONFIG);
    avroReflectionAllowNull = config
        .getBoolean(KafkaAvroDeserializerConfig.AVRO_REFLECTION_ALLOW_NULL_CONFIG);
    avroUseLogicalTypeConverters = config
            .getBoolean(KafkaAvroSerializerConfig.AVRO_USE_LOGICAL_TYPE_CONVERTERS_CONFIG);
  }
   `
It will also fix https://github.com/provectus/kafka-ui/issues/2764
@tkaszuba thank you for suggestion, but unfortunately it is not so simple (we know about that properties).
1. we need to implement json string -> avro record translation to support serialization. Currently we use ` AvroSchemaUtils.toObject(json,  schema)` , but that does not support logical types.
2. we need to support avro schema -> json schema translation (used for samples generation in UI). And that code is now written from scratch (`AvroJsonSchemaConverter`),  so it also need to support logical types. 

So, there is some non-trivial things to be done 😃
ok, I have it working so I guess we'll just fork it for the time being
while we wait for a proper fix.

Either way I'm sending over my patch, perhaps it will come in handy.

btw: Thank you for this wonderful product! It's way better than confluent
control center! Congrats!


On Fri, 21 Apr 2023 at 18:54, Ilya Kuramshin ***@***.***>
wrote:

> @tkaszuba <https://github.com/tkaszuba> thank you for suggestion, but
> unfortunately it is not so simple (we know about that properties).
>
>    1. we need to implement json string -> avro record translation to
>    support serialization. Currently we use AvroSchemaUtils.toObject(json,
>    schema) , but that does not support logical types.
>    2. we need to support avro schema -> json schema translation (used for
>    samples generation in UI). And that code is now written from scratch (
>    AvroJsonSchemaConverter), so it also need to support logical types.
>
> So, there is some non-trivial things to be done 😃
>
> —
> Reply to this email directly, view it on GitHub
> <https://github.com/provectus/kafka-ui/issues/2943#issuecomment-1518097703>,
> or unsubscribe
> <https://github.com/notifications/unsubscribe-auth/AG2T7OV3WW2X3PCXKDPKXP3XCK3UVANCNFSM6AAAAAASBGBLJE>
> .
> You are receiving this because you were mentioned.Message ID:
> ***@***.***>
>


Pull request review comments:

Patch that resolved the issue:
diff --git a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/exception/JsonToAvroConversionException.java b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/exception/JsonToAvroConversionException.java
new file mode 100644
index 00000000000..5b3910f4cf3
--- /dev/null
+++ b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/exception/JsonToAvroConversionException.java
@@ -0,0 +1,7 @@
+package com.provectus.kafka.ui.exception;
+
+public class JsonToAvroConversionException extends ValidationException {
+  public JsonToAvroConversionException(String message) {
+    super(message);
+  }
+}
diff --git a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/AvroSchemaRegistrySerializer.java b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/AvroSchemaRegistrySerializer.java
index 3c4a5008552..164938bfc70 100644
--- a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/AvroSchemaRegistrySerializer.java
+++ b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/AvroSchemaRegistrySerializer.java
@@ -1,12 +1,13 @@
 package com.provectus.kafka.ui.serdes.builtin.sr;
 
+import com.provectus.kafka.ui.util.jsonschema.JsonAvroConversion;
 import io.confluent.kafka.schemaregistry.ParsedSchema;
 import io.confluent.kafka.schemaregistry.avro.AvroSchema;
-import io.confluent.kafka.schemaregistry.avro.AvroSchemaUtils;
 import io.confluent.kafka.schemaregistry.client.SchemaMetadata;
 import io.confluent.kafka.schemaregistry.client.SchemaRegistryClient;
 import io.confluent.kafka.serializers.AbstractKafkaSchemaSerDeConfig;
 import io.confluent.kafka.serializers.KafkaAvroSerializer;
+import io.confluent.kafka.serializers.KafkaAvroSerializerConfig;
 import java.util.Map;
 import org.apache.kafka.common.serialization.Serializer;
 
@@ -25,6 +26,7 @@ protected Serializer<Object> createSerializer(SchemaRegistryClient client) {
         Map.of(
             "schema.registry.url", "wontbeused",
             AbstractKafkaSchemaSerDeConfig.AUTO_REGISTER_SCHEMAS, false,
+            KafkaAvroSerializerConfig.AVRO_USE_LOGICAL_TYPE_CONVERTERS_CONFIG, true,
             AbstractKafkaSchemaSerDeConfig.USE_LATEST_VERSION, true
         ),
         isKey
@@ -35,7 +37,7 @@ protected Serializer<Object> createSerializer(SchemaRegistryClient client) {
   @Override
   protected Object serialize(String value, ParsedSchema schema) {
     try {
-      return AvroSchemaUtils.toObject(value, (AvroSchema) schema);
+      return JsonAvroConversion.convertJsonToAvro(value, ((AvroSchema) schema).rawSchema());
     } catch (Throwable e) {
       throw new RuntimeException("Failed to serialize record for topic " + topic, e);
     }
diff --git a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/MessageFormatter.java b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/MessageFormatter.java
index 52e8c6f33a4..40073d85347 100644
--- a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/MessageFormatter.java
+++ b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/serdes/builtin/sr/MessageFormatter.java
@@ -3,9 +3,12 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.google.protobuf.Message;
 import com.google.protobuf.util.JsonFormat;
+import com.provectus.kafka.ui.util.jsonschema.JsonAvroConversion;
 import io.confluent.kafka.schemaregistry.avro.AvroSchemaUtils;
 import io.confluent.kafka.schemaregistry.client.SchemaRegistryClient;
+import io.confluent.kafka.serializers.AbstractKafkaSchemaSerDeConfig;
 import io.confluent.kafka.serializers.KafkaAvroDeserializer;
+import io.confluent.kafka.serializers.KafkaAvroDeserializerConfig;
 import io.confluent.kafka.serializers.json.KafkaJsonSchemaDeserializer;
 import io.confluent.kafka.serializers.protobuf.KafkaProtobufDeserializer;
 import java.util.Map;
@@ -28,16 +31,22 @@ class AvroMessageFormatter implements MessageFormatter {
 
     AvroMessageFormatter(SchemaRegistryClient client) {
       this.avroDeserializer = new KafkaAvroDeserializer(client);
+      this.avroDeserializer.configure(
+          Map.of(
+              AbstractKafkaSchemaSerDeConfig.SCHEMA_REGISTRY_URL_CONFIG, "wontbeused",
+              KafkaAvroDeserializerConfig.SPECIFIC_AVRO_READER_CONFIG, false,
+              KafkaAvroDeserializerConfig.SCHEMA_REFLECTION_CONFIG, false,
+              KafkaAvroDeserializerConfig.AVRO_USE_LOGICAL_TYPE_CONVERTERS_CONFIG, true
+          ),
+          false
+      );
     }
 
     @Override
-    @SneakyThrows
     public String format(String topic, byte[] value) {
-      // deserialized will have type, that depends on schema type (record or primitive),
-      // AvroSchemaUtils.toJson(...) method will take it into account
       Object deserialized = avroDeserializer.deserialize(topic, value);
-      byte[] jsonBytes = AvroSchemaUtils.toJson(deserialized);
-      return new String(jsonBytes);
+      var schema = AvroSchemaUtils.getSchema(deserialized);
+      return JsonAvroConversion.convertAvroToJson(deserialized, schema).toString();
     }
   }
 
diff --git a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/AvroJsonSchemaConverter.java b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/AvroJsonSchemaConverter.java
index d2cd0e65f39..56737d7a612 100644
--- a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/AvroJsonSchemaConverter.java
+++ b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/AvroJsonSchemaConverter.java
@@ -5,6 +5,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.stream.Collectors;
 import org.apache.avro.Schema;
 import reactor.util.function.Tuple2;
@@ -40,6 +41,10 @@ private FieldSchema convertField(Schema.Field field, Map<String, FieldSchema> de
 
   private FieldSchema convertSchema(Schema schema,
                                     Map<String, FieldSchema> definitions, boolean isRoot) {
+    Optional<FieldSchema> logicalTypeSchema = JsonAvroConversion.LogicalTypeConversion.getJsonSchema(schema);
+    if (logicalTypeSchema.isPresent()) {
+      return logicalTypeSchema.get();
+    }
     if (!schema.isUnion()) {
       JsonType type = convertType(schema);
       switch (type.getType()) {
@@ -66,7 +71,6 @@ private FieldSchema convertSchema(Schema schema,
     }
   }
 
-
   // this method formats json-schema field in a way
   // to fit avro-> json encoding rules (https://avro.apache.org/docs/1.11.1/specification/_print/#json-encoding)
   private FieldSchema createUnionSchema(Schema schema, Map<String, FieldSchema> definitions) {
diff --git a/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversion.java b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversion.java
new file mode 100644
index 00000000000..d2114dd971c
--- /dev/null
+++ b/kafka-ui-api/src/main/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversion.java
@@ -0,0 +1,503 @@
+package com.provectus.kafka.ui.util.jsonschema;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.BooleanNode;
+import com.fasterxml.jackson.databind.node.DecimalNode;
+import com.fasterxml.jackson.databind.node.DoubleNode;
+import com.fasterxml.jackson.databind.node.FloatNode;
+import com.fasterxml.jackson.databind.node.IntNode;
+import com.fasterxml.jackson.databind.node.JsonNodeType;
+import com.fasterxml.jackson.databind.node.LongNode;
+import com.fasterxml.jackson.databind.node.NullNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.fasterxml.jackson.databind.node.TextNode;
+import com.google.common.collect.Lists;
+import com.provectus.kafka.ui.exception.JsonToAvroConversionException;
+import io.confluent.kafka.serializers.AvroData;
+import java.math.BigDecimal;
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.ZoneOffset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.TimeUnit;
+import java.util.function.BiFunction;
+import java.util.stream.Stream;
+import lombok.SneakyThrows;
+import org.apache.avro.Schema;
+import org.apache.avro.generic.GenericData;
+
+// json <-> avro
+public class JsonAvroConversion {
+
+  private static final JsonMapper MAPPER = new JsonMapper();
+
+  // converts json into Object that is expected input for KafkaAvroSerializer
+  // (with AVRO_USE_LOGICAL_TYPE_CONVERTERS flat enabled!)
+  @SneakyThrows
+  public static Object convertJsonToAvro(String jsonString, Schema avroSchema) {
+    JsonNode rootNode = MAPPER.readTree(jsonString);
+    return convert(rootNode, avroSchema);
+  }
+
+  private static Object convert(JsonNode node, Schema avroSchema) {
+    return switch (avroSchema.getType()) {
+      case RECORD -> {
+        assertJsonType(node, JsonNodeType.OBJECT);
+        var rec = new GenericData.Record(avroSchema);
+        for (Schema.Field field : avroSchema.getFields()) {
+          if (node.has(field.name()) && !node.get(field.name()).isNull()) {
+            rec.put(field.name(), convert(node.get(field.name()), field.schema()));
+          }
+        }
+        yield rec;
+      }
+      case MAP -> {
+        assertJsonType(node, JsonNodeType.OBJECT);
+        var map = new LinkedHashMap<String, Object>();
+        var valueSchema = avroSchema.getValueType();
+        node.fields().forEachRemaining(f -> map.put(f.getKey(), convert(f.getValue(), valueSchema)));
+        yield map;
+      }
+      case ARRAY -> {
+        assertJsonType(node, JsonNodeType.ARRAY);
+        var lst = new ArrayList<>();
+        node.elements().forEachRemaining(e -> lst.add(convert(e, avroSchema.getElementType())));
+        yield lst;
+      }
+      case ENUM -> {
+        assertJsonType(node, JsonNodeType.STRING);
+        String symbol = node.textValue();
+        if (!avroSchema.getEnumSymbols().contains(symbol)) {
+          throw new JsonToAvroConversionException("%s is not a part of enum symbols [%s]"
+              .formatted(symbol, avroSchema.getEnumSymbols()));
+        }
+        yield new GenericData.EnumSymbol(avroSchema, symbol);
+      }
+      case UNION -> {
+        // for types from enum (other than null) payload should be an object with single key == name of type
+        // ex: schema = [ "null", "int", "string" ], possible payloads = null, { "string": "str" },  { "int": 123 }
+        if (node.isNull() && avroSchema.getTypes().contains(Schema.create(Schema.Type.NULL))) {
+          yield null;
+        }
+
+        assertJsonType(node, JsonNodeType.OBJECT);
+        var elements = Lists.newArrayList(node.fields());
+        if (elements.size() != 1) {
+          throw new JsonToAvroConversionException(
+              "UNION field value should be an object with single field == type name");
+        }
+        var typeNameToValue = elements.get(0);
+        for (Schema unionType : avroSchema.getTypes()) {
+          if (typeNameToValue.getKey().equals(unionType.getFullName())) {
+            yield convert(typeNameToValue.getValue(), unionType);
+          }
+        }
+        throw new JsonToAvroConversionException(
+            "json value '%s' is cannot be converted to any of union types [%s]"
+                .formatted(node, avroSchema.getTypes()));
+      }
+      case STRING -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(node, avroSchema);
+        }
+        assertJsonType(node, JsonNodeType.STRING);
+        yield node.textValue();
+      }
+      case LONG -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(node, avroSchema);
+        }
+        assertJsonType(node, JsonNodeType.NUMBER);
+        assertJsonNumberType(node, JsonParser.NumberType.LONG, JsonParser.NumberType.INT);
+        yield node.longValue();
+      }
+      case INT -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(node, avroSchema);
+        }
+        assertJsonType(node, JsonNodeType.NUMBER);
+        assertJsonNumberType(node, JsonParser.NumberType.INT);
+        yield node.intValue();
+      }
+      case FLOAT -> {
+        assertJsonType(node, JsonNodeType.NUMBER);
+        assertJsonNumberType(node, JsonParser.NumberType.DOUBLE, JsonParser.NumberType.FLOAT);
+        yield node.floatValue();
+      }
+      case DOUBLE -> {
+        assertJsonType(node, JsonNodeType.NUMBER);
+        assertJsonNumberType(node, JsonParser.NumberType.DOUBLE, JsonParser.NumberType.FLOAT);
+        yield node.doubleValue();
+      }
+      case BOOLEAN -> {
+        assertJsonType(node, JsonNodeType.BOOLEAN);
+        yield node.booleanValue();
+      }
+      case NULL -> {
+        assertJsonType(node, JsonNodeType.NULL);
+        yield null;
+      }
+      case BYTES -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(node, avroSchema);
+        }
+        assertJsonType(node, JsonNodeType.STRING);
+        // logic copied from JsonDecoder::readBytes
+        yield ByteBuffer.wrap(node.textValue().getBytes(StandardCharsets.ISO_8859_1));
+      }
+      case FIXED -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(node, avroSchema);
+        }
+        assertJsonType(node, JsonNodeType.STRING);
+        byte[] bytes = node.textValue().getBytes(StandardCharsets.ISO_8859_1);
+        if (bytes.length != avroSchema.getFixedSize()) {
+          throw new JsonToAvroConversionException(
+              "Fixed field has unexpected size %d (should be %d)"
+                  .formatted(bytes.length, avroSchema.getFixedSize()));
+        }
+        yield new GenericData.Fixed(avroSchema, bytes);
+      }
+    };
+  }
+
+  // converts output of KafkaAvroDeserializer (with AVRO_USE_LOGICAL_TYPE_CONVERTERS flat enabled!) into json.
+  // Note: conversion should be compatible with AvroJsonSchemaConverter logic!
+  public static JsonNode convertAvroToJson(Object obj, Schema avroSchema) {
+    if (obj == null) {
+      return NullNode.getInstance();
+    }
+    return switch (avroSchema.getType()) {
+      case RECORD -> {
+        var rec = (GenericData.Record) obj;
+        ObjectNode node = MAPPER.createObjectNode();
+        for (Schema.Field field : avroSchema.getFields()) {
+          var fieldVal = rec.get(field.name());
+          if (fieldVal != null) {
+            node.set(field.name(), convertAvroToJson(fieldVal, field.schema()));
+          }
+        }
+        yield node;
+      }
+      case MAP -> {
+        ObjectNode node = MAPPER.createObjectNode();
+        ((Map) obj).forEach((k, v) -> node.set(k.toString(), convertAvroToJson(v, avroSchema.getValueType())));
+        yield node;
+      }
+      case ARRAY -> {
+        var list = (List<Object>) obj;
+        ArrayNode node = MAPPER.createArrayNode();
+        list.forEach(e -> node.add(convertAvroToJson(e, avroSchema.getElementType())));
+        yield node;
+      }
+      case ENUM -> {
+        yield new TextNode(obj.toString());
+      }
+      case UNION -> {
+        ObjectNode node = MAPPER.createObjectNode();
+        int unionIdx = AvroData.getGenericData().resolveUnion(avroSchema, obj);
+        Schema unionType = avroSchema.getTypes().get(unionIdx);
+        node.set(unionType.getFullName(), convertAvroToJson(obj, unionType));
+        yield node;
+      }
+      case STRING -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(obj, avroSchema);
+        }
+        yield new TextNode(obj.toString());
+      }
+      case LONG -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(obj, avroSchema);
+        }
+        yield new LongNode((Long) obj);
+      }
+      case INT -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(obj, avroSchema);
+        }
+        yield new IntNode((Integer) obj);
+      }
+      case FLOAT -> new FloatNode((Float) obj);
+      case DOUBLE -> new DoubleNode((Double) obj);
+      case BOOLEAN -> BooleanNode.valueOf((Boolean) obj);
+      case NULL -> NullNode.getInstance();
+      case BYTES -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(obj, avroSchema);
+        }
+        ByteBuffer bytes = (ByteBuffer) obj;
+        //see JsonEncoder::writeByteArray
+        yield new TextNode(new String(bytes.array(), StandardCharsets.ISO_8859_1));
+      }
+      case FIXED -> {
+        if (isLogicalType(avroSchema)) {
+          yield processLogicalType(obj, avroSchema);
+        }
+        var fixed = (GenericData.Fixed) obj;
+        yield new TextNode(new String(fixed.bytes(), StandardCharsets.ISO_8859_1));
+      }
+    };
+  }
+
+  private static Object processLogicalType(JsonNode node, Schema schema) {
+    return findConversion(schema)
+        .map(c -> c.jsonToAvroConversion.apply(node, schema))
+        .orElseThrow(() ->
+            new JsonToAvroConversionException("'%s' logical type is not supported"
+                .formatted(schema.getLogicalType().getName())));
+  }
+
+  private static JsonNode processLogicalType(Object obj, Schema schema) {
+    return findConversion(schema)
+        .map(c -> c.avroToJsonConversion.apply(obj, schema))
+        .orElseThrow(() ->
+            new JsonToAvroConversionException("'%s' logical type is not supported"
+                .formatted(schema.getLogicalType().getName())));
+  }
+
+  private static Optional<LogicalTypeConversion> findConversion(Schema schema) {
+    String logicalTypeName = schema.getLogicalType().getName();
+    return Stream.of(LogicalTypeConversion.values())
+        .filter(t -> t.name.equalsIgnoreCase(logicalTypeName))
+        .findFirst();
+  }
+
+  private static boolean isLogicalType(Schema schema) {
+    return schema.getLogicalType() != null;
+  }
+
+  private static void assertJsonType(JsonNode node, JsonNodeType... allowedTypes) {
+    if (Stream.of(allowedTypes).noneMatch(t -> node.getNodeType() == t)) {
+      throw new JsonToAvroConversionException(
+          "%s node has unexpected type, allowed types %s, actual type %s"
+              .formatted(node, Arrays.toString(allowedTypes), node.getNodeType()));
+    }
+  }
+
+  private static void assertJsonNumberType(JsonNode node, JsonParser.NumberType... allowedTypes) {
+    if (Stream.of(allowedTypes).noneMatch(t -> node.numberType() == t)) {
+      throw new JsonToAvroConversionException(
+          "%s node has unexpected numeric type, allowed types %s, actual type %s"
+              .formatted(node, Arrays.toString(allowedTypes), node.numberType()));
+    }
+  }
+
+  enum LogicalTypeConversion {
+
+    UUID("uuid",
+        (node, schema) -> {
+          assertJsonType(node, JsonNodeType.STRING);
+          return java.util.UUID.fromString(node.asText());
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("uuid"))))
+    ),
+
+    DECIMAL("decimal",
+        (node, schema) -> {
+          if (node.isTextual()) {
+            return new BigDecimal(node.asText());
+          } else if (node.isNumber()) {
+            return new BigDecimal(node.numberValue().toString());
+          }
+          throw new JsonToAvroConversionException(
+              "node '%s' can't be converted to decimal logical type"
+                  .formatted(node));
+        },
+        (obj, schema) -> {
+          return new DecimalNode((BigDecimal) obj);
+        },
+        new SimpleFieldSchema(new SimpleJsonType(JsonType.Type.NUMBER))
+    ),
+
+    DATE("date",
+        (node, schema) -> {
+          if (node.isInt()) {
+            return LocalDate.ofEpochDay(node.intValue());
+          } else if (node.isTextual()) {
+            return LocalDate.parse(node.asText());
+          } else {
+            throw new JsonToAvroConversionException(
+                "node '%s' can't be converted to date logical type"
+                    .formatted(node));
+          }
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("date"))))
+    ),
+
+    TIME_MILLIS("time-millis",
+        (node, schema) -> {
+          if (node.isIntegralNumber()) {
+            return LocalTime.ofNanoOfDay(TimeUnit.MILLISECONDS.toNanos(node.longValue()));
+          } else if (node.isTextual()) {
+            return LocalTime.parse(node.asText());
+          } else {
+            throw new JsonToAvroConversionException(
+                "node '%s' can't be converted to time-millis logical type"
+                    .formatted(node));
+          }
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("time"))))
+    ),
+
+    TIME_MICROS("time-micros",
+        (node, schema) -> {
+          if (node.isIntegralNumber()) {
+            return LocalTime.ofNanoOfDay(TimeUnit.MICROSECONDS.toNanos(node.longValue()));
+          } else if (node.isTextual()) {
+            return LocalTime.parse(node.asText());
+          } else {
+            throw new JsonToAvroConversionException(
+                "node '%s' can't be converted to time-micros logical type"
+                    .formatted(node));
+          }
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("time"))))
+    ),
+
+    TIMESTAMP_MILLIS("timestamp-millis",
+        (node, schema) -> {
+          if (node.isIntegralNumber()) {
+            return Instant.ofEpochMilli(node.longValue());
+          } else if (node.isTextual()) {
+            return Instant.parse(node.asText());
+          } else {
+            throw new JsonToAvroConversionException(
+                "node '%s' can't be converted to timestamp-millis logical type"
+                    .formatted(node));
+          }
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("date-time"))))
+    ),
+
+    TIMESTAMP_MICROS("timestamp-micros",
+        (node, schema) -> {
+          if (node.isIntegralNumber()) {
+            // TimeConversions.TimestampMicrosConversion for impl
+            long microsFromEpoch = node.longValue();
+            long epochSeconds = microsFromEpoch / (1_000_000L);
+            long nanoAdjustment = (microsFromEpoch % (1_000_000L)) * 1_000L;
+            return Instant.ofEpochSecond(epochSeconds, nanoAdjustment);
+          } else if (node.isTextual()) {
+            return Instant.parse(node.asText());
+          } else {
+            throw new JsonToAvroConversionException(
+                "node '%s' can't be converted to timestamp-millis logical type"
+                    .formatted(node));
+          }
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("date-time"))))
+    ),
+
+    LOCAL_TIMESTAMP_MILLIS("local-timestamp-millis",
+        (node, schema) -> {
+          if (node.isTextual()) {
+            return LocalDateTime.parse(node.asText());
+          }
+          // TimeConversions.TimestampMicrosConversion for impl
+          Instant instant = (Instant) TIMESTAMP_MILLIS.jsonToAvroConversion.apply(node, schema);
+          return LocalDateTime.ofInstant(instant, ZoneOffset.UTC);
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("date-time"))))
+    ),
+
+    LOCAL_TIMESTAMP_MICROS("local-timestamp-micros",
+        (node, schema) -> {
+          if (node.isTextual()) {
+            return LocalDateTime.parse(node.asText());
+          }
+          Instant instant = (Instant) TIMESTAMP_MICROS.jsonToAvroConversion.apply(node, schema);
+          return LocalDateTime.ofInstant(instant, ZoneOffset.UTC);
+        },
+        (obj, schema) -> {
+          return new TextNode(obj.toString());
+        },
+        new SimpleFieldSchema(
+            new SimpleJsonType(
+                JsonType.Type.STRING,
+                Map.of("format", new TextNode("date-time"))))
+    );
+
+    private final String name;
+    private final BiFunction<JsonNode, Schema, Object> jsonToAvroConversion;
+    private final BiFunction<Object, Schema, JsonNode> avroToJsonConversion;
+    private final FieldSchema jsonSchema;
+
+    LogicalTypeConversion(String name,
+                          BiFunction<JsonNode, Schema, Object> jsonToAvroConversion,
+                          BiFunction<Object, Schema, JsonNode> avroToJsonConversion,
+                          FieldSchema jsonSchema) {
+      this.name = name;
+      this.jsonToAvroConversion = jsonToAvroConversion;
+      this.avroToJsonConversion = avroToJsonConversion;
+      this.jsonSchema = jsonSchema;
+    }
+
+    static Optional<FieldSchema> getJsonSchema(Schema schema) {
+      if (schema.getLogicalType() == null) {
+        return Optional.empty();
+      }
+      String logicalTypeName = schema.getLogicalType().getName();
+      return Stream.of(JsonAvroConversion.LogicalTypeConversion.values())
+          .filter(t -> t.name.equalsIgnoreCase(logicalTypeName))
+          .map(c -> c.jsonSchema)
+          .findFirst();
+    }
+  }
+
+
+}


Test patch:
diff --git a/kafka-ui-api/src/test/java/com/provectus/kafka/ui/serdes/builtin/sr/SchemaRegistrySerdeTest.java b/kafka-ui-api/src/test/java/com/provectus/kafka/ui/serdes/builtin/sr/SchemaRegistrySerdeTest.java
index 4ea2bf3c2ac..b70450cea5c 100644
--- a/kafka-ui-api/src/test/java/com/provectus/kafka/ui/serdes/builtin/sr/SchemaRegistrySerdeTest.java
+++ b/kafka-ui-api/src/test/java/com/provectus/kafka/ui/serdes/builtin/sr/SchemaRegistrySerdeTest.java
@@ -2,13 +2,12 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.provectus.kafka.ui.serde.api.DeserializeResult;
 import com.provectus.kafka.ui.serde.api.SchemaDescription;
 import com.provectus.kafka.ui.serde.api.Serde;
+import com.provectus.kafka.ui.util.jsonschema.JsonAvroConversion;
 import io.confluent.kafka.schemaregistry.avro.AvroSchema;
-import io.confluent.kafka.schemaregistry.avro.AvroSchemaUtils;
 import io.confluent.kafka.schemaregistry.client.MockSchemaRegistryClient;
 import io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException;
 import java.io.ByteArrayOutputStream;
@@ -54,7 +53,8 @@ void returnsSchemaDescriptionIfSchemaRegisteredInSR(String topic, String subject
 
     SchemaDescription schemaDescription = schemaOptional.get();
     assertThat(schemaDescription.getSchema())
-        .contains("{\"$id\":\"int\",\"$schema\":\"https://json-schema.org/draft/2020-12/schema\",\"type\":\"integer\"}");
+        .contains(
+            "{\"$id\":\"int\",\"$schema\":\"https://json-schema.org/draft/2020-12/schema\",\"type\":\"integer\"}");
     assertThat(schemaDescription.getAdditionalProperties())
         .containsOnlyKeys("subject", "schemaId", "latestVersion", "type")
         .containsEntry("subject", subject)
@@ -189,7 +189,8 @@ void canSerializeReturnsFalseIfSubjectDoesNotExist() {
     assertThat(serde.canSerialize(topic, Serde.Target.VALUE)).isFalse();
   }
 
-  private void assertJsonsEqual(String expected, String actual) throws JsonProcessingException {
+  @SneakyThrows
+  private void assertJsonsEqual(String expected, String actual) {
     var mapper = new JsonMapper();
     assertThat(mapper.readTree(actual)).isEqualTo(mapper.readTree(expected));
   }
@@ -211,9 +212,174 @@ private byte[] jsonToAvro(String json, AvroSchema schema) {
     GenericDatumWriter<Object> writer = new GenericDatumWriter<>(schema.rawSchema());
     ByteArrayOutputStream output = new ByteArrayOutputStream();
     Encoder encoder = EncoderFactory.get().binaryEncoder(output, null);
-    writer.write(AvroSchemaUtils.toObject(json, schema), encoder);
+    writer.write(JsonAvroConversion.convertJsonToAvro(json, schema.rawSchema()), encoder);
     encoder.flush();
     return output.toByteArray();
   }
 
+  @Test
+  void avroFieldsRepresentationIsConsistentForSerializationAndDeserialization() throws Exception {
+    AvroSchema schema = new AvroSchema(
+        """
+             {
+               "type": "record",
+               "name": "TestAvroRecord",
+               "fields": [
+                 {
+                   "name": "f_int",
+                   "type": "int"
+                 },
+                 {
+                   "name": "f_long",
+                   "type": "long"
+                 },
+                 {
+                   "name": "f_string",
+                   "type": "string"
+                 },
+                 {
+                   "name": "f_boolean",
+                   "type": "boolean"
+                 },
+                 {
+                   "name": "f_float",
+                   "type": "float"
+                 },
+                 {
+                   "name": "f_double",
+                   "type": "double"
+                 },
+                 {
+                   "name": "f_enum",
+                   "type" : {
+                    "type": "enum",
+                    "name": "Suit",
+                    "symbols" : ["SPADES", "HEARTS", "DIAMONDS", "CLUBS"]
+                   }
+                 },
+                 {
+                  "name": "f_map",
+                  "type": {
+                     "type": "map",
+                     "values" : "string",
+                     "default": {}
+                   }
+                 },
+                 {
+                  "name": "f_union",
+                  "type": ["null", "string", "int" ]
+                 },
+                 {
+                  "name": "f_optional_to_test_not_filled_case",
+                  "type": [ "null", "string"]
+                 },
+                 {
+                     "name" : "f_fixed",
+                     "type" : { "type" : "fixed" ,"size" : 8, "name": "long_encoded" }
+                   },
+                   {
+                     "name" : "f_bytes",
+                     "type": "bytes"
+                   }
+               ]
+            }"""
+    );
+
+    String jsonPayload = """
+        {
+          "f_int": 123,
+          "f_long": 4294967294,
+          "f_string": "string here",
+          "f_boolean": true,
+          "f_float": 123.1,
+          "f_double": 123456.123456,
+          "f_enum": "SPADES",
+          "f_map": { "k1": "string value" },
+          "f_union": { "int": 123 },
+          "f_fixed": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\u0004Ò",
+          "f_bytes": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\t)"
+        }
+        """;
+
+    registryClient.register("test-value", schema);
+    assertSerdeCycle("test", jsonPayload);
+  }
+
+  @Test
+  void avroLogicalTypesRepresentationIsConsistentForSerializationAndDeserialization() throws Exception {
+    AvroSchema schema = new AvroSchema(
+        """
+             {
+               "type": "record",
+               "name": "TestAvroRecord",
+               "fields": [
+                 {
+                   "name": "lt_date",
+                   "type": { "type": "int", "logicalType": "date" }
+                 },
+                 {
+                   "name": "lt_uuid",
+                   "type": { "type": "string", "logicalType": "uuid" }
+                 },
+                 {
+                   "name": "lt_decimal",
+                   "type": { "type": "bytes", "logicalType": "decimal", "precision": 22, "scale":10 }
+                 },
+                 {
+                   "name": "lt_time_millis",
+                   "type": { "type": "int", "logicalType": "time-millis"}
+                 },
+                 {
+                   "name": "lt_time_micros",
+                   "type": { "type": "long", "logicalType": "time-micros"}
+                 },
+                 {
+                   "name": "lt_timestamp_millis",
+                   "type": { "type": "long", "logicalType": "timestamp-millis" }
+                 },
+                 {
+                   "name": "lt_timestamp_micros",
+                   "type": { "type": "long", "logicalType": "timestamp-micros" }
+                 },
+                 {
+                   "name": "lt_local_timestamp_millis",
+                   "type": { "type": "long", "logicalType": "local-timestamp-millis" }
+                 },
+                 {
+                   "name": "lt_local_timestamp_micros",
+                   "type": { "type": "long", "logicalType": "local-timestamp-micros" }
+                 }
+               ]
+            }"""
+    );
+
+    String jsonPayload = """
+        {
+          "lt_date":"1991-08-14",
+          "lt_decimal": 2.1617413862327545E11,
+          "lt_time_millis": "10:15:30.001",
+          "lt_time_micros": "10:15:30.123456",
+          "lt_uuid": "a37b75ca-097c-5d46-6119-f0637922e908",
+          "lt_timestamp_millis": "2007-12-03T10:15:30.123Z",
+          "lt_timestamp_micros": "2007-12-03T10:15:30.123456Z",
+          "lt_local_timestamp_millis": "2017-12-03T10:15:30.123",
+          "lt_local_timestamp_micros": "2017-12-03T10:15:30.123456"
+        }
+        """;
+
+    registryClient.register("test-value", schema);
+    assertSerdeCycle("test", jsonPayload);
+  }
+
+  // 1. serialize input json to binary
+  // 2. deserialize from binary
+  // 3. check that deserialized version equal to input
+  void assertSerdeCycle(String topic, String jsonInput) {
+    byte[] serializedBytes = serde.serializer(topic, Serde.Target.VALUE).serialize(jsonInput);
+    var deserializedJson = serde.deserializer(topic, Serde.Target.VALUE)
+        .deserialize(null, serializedBytes)
+        .getResult();
+    assertJsonsEqual(jsonInput, deserializedJson);
+  }
+
 }
diff --git a/kafka-ui-api/src/test/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversionTest.java b/kafka-ui-api/src/test/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversionTest.java
new file mode 100644
index 00000000000..0e9c291707e
--- /dev/null
+++ b/kafka-ui-api/src/test/java/com/provectus/kafka/ui/util/jsonschema/JsonAvroConversionTest.java
@@ -0,0 +1,621 @@
+package com.provectus.kafka.ui.util.jsonschema;
+
+import static com.provectus.kafka.ui.util.jsonschema.JsonAvroConversion.convertAvroToJson;
+import static com.provectus.kafka.ui.util.jsonschema.JsonAvroConversion.convertJsonToAvro;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.databind.node.BooleanNode;
+import com.fasterxml.jackson.databind.node.DoubleNode;
+import com.fasterxml.jackson.databind.node.FloatNode;
+import com.fasterxml.jackson.databind.node.IntNode;
+import com.fasterxml.jackson.databind.node.LongNode;
+import com.fasterxml.jackson.databind.node.TextNode;
+import com.google.common.primitives.Longs;
+import io.confluent.kafka.schemaregistry.avro.AvroSchema;
+import java.math.BigDecimal;
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import lombok.SneakyThrows;
+import org.apache.avro.Schema;
+import org.apache.avro.generic.GenericData;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+class JsonAvroConversionTest {
+
+  // checking conversion from json to KafkaAvroSerializer-compatible avro objects
+  @Nested
+  class FromJsonToAvro {
+
+    @Test
+    void primitiveRoot() {
+      assertThat(convertJsonToAvro("\"str\"", createSchema("\"string\"")))
+          .isEqualTo("str");
+
+      assertThat(convertJsonToAvro("123", createSchema("\"int\"")))
+          .isEqualTo(123);
+
+      assertThat(convertJsonToAvro("123", createSchema("\"long\"")))
+          .isEqualTo(123L);
+
+      assertThat(convertJsonToAvro("123.123", createSchema("\"float\"")))
+          .isEqualTo(123.123F);
+
+      assertThat(convertJsonToAvro("12345.12345", createSchema("\"double\"")))
+          .isEqualTo(12345.12345);
+    }
+
+    @Test
+    void primitiveTypedFields() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "f_int",
+                     "type": "int"
+                   },
+                   {
+                     "name": "f_long",
+                     "type": "long"
+                   },
+                   {
+                     "name": "f_string",
+                     "type": "string"
+                   },
+                   {
+                     "name": "f_boolean",
+                     "type": "boolean"
+                   },
+                   {
+                     "name": "f_float",
+                     "type": "float"
+                   },
+                   {
+                     "name": "f_double",
+                     "type": "double"
+                   },
+                   {
+                     "name": "f_enum",
+                     "type" : {
+                      "type": "enum",
+                      "name": "Suit",
+                      "symbols" : ["SPADES", "HEARTS", "DIAMONDS", "CLUBS"]
+                     }
+                   },
+                   {
+                     "name" : "f_fixed",
+                     "type" : { "type" : "fixed" ,"size" : 8, "name": "long_encoded" }
+                   },
+                   {
+                     "name" : "f_bytes",
+                     "type": "bytes"
+                   }
+                 ]
+              }"""
+      );
+
+      String jsonPayload = """
+          {
+            "f_int": 123,
+            "f_long": 4294967294,
+            "f_string": "string here",
+            "f_boolean": true,
+            "f_float": 123.1,
+            "f_double": 123456.123456,
+            "f_enum": "SPADES",
+            "f_fixed": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\u0004Ò",
+            "f_bytes": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\t)"
+          }
+          """;
+
+      var converted = convertJsonToAvro(jsonPayload, schema);
+      assertThat(converted).isInstanceOf(GenericData.Record.class);
+
+      var record = (GenericData.Record) converted;
+      assertThat(record.get("f_int")).isEqualTo(123);
+      assertThat(record.get("f_long")).isEqualTo(4294967294L);
+      assertThat(record.get("f_string")).isEqualTo("string here");
+      assertThat(record.get("f_boolean")).isEqualTo(true);
+      assertThat(record.get("f_float")).isEqualTo(123.1f);
+      assertThat(record.get("f_double")).isEqualTo(123456.123456);
+      assertThat(record.get("f_enum"))
+          .isEqualTo(
+              new GenericData.EnumSymbol(
+                  schema.getField("f_enum").schema(),
+                  "SPADES"
+              )
+          );
+      assertThat(((GenericData.Fixed) record.get("f_fixed")).bytes()).isEqualTo(Longs.toByteArray(1234L));
+      assertThat(((ByteBuffer) record.get("f_bytes")).array()).isEqualTo(Longs.toByteArray(2345L));
+    }
+
+    @Test
+    void unionRoot() {
+      var schema = createSchema("[ \"null\", \"string\", \"int\" ]");
+
+      var converted = convertJsonToAvro("{\"string\":\"string here\"}", schema);
+      assertThat(converted).isEqualTo("string here");
+
+      converted = convertJsonToAvro("{\"int\": 123}", schema);
+      assertThat(converted).isEqualTo(123);
+
+      converted = convertJsonToAvro("null", schema);
+      assertThat(converted).isEqualTo(null);
+    }
+
+    @Test
+    void unionField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "namespace": "com.test",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "f_union",
+                     "type": [ "null", "int", "TestAvroRecord"]
+                   }
+                 ]
+              }"""
+      );
+
+      String jsonPayload = "{ \"f_union\": null }";
+
+      var record = (GenericData.Record) convertJsonToAvro(jsonPayload, schema);
+      assertThat(record.get("f_union")).isNull();
+
+      jsonPayload = "{ \"f_union\": { \"int\": 123 } }";
+      record = (GenericData.Record) convertJsonToAvro(jsonPayload, schema);
+      assertThat(record.get("f_union")).isEqualTo(123);
+
+      //inner-record's name should be fully-qualified!
+      jsonPayload = "{ \"f_union\": { \"com.test.TestAvroRecord\": { \"f_union\": { \"int\": 123  } } } }";
+      record = (GenericData.Record) convertJsonToAvro(jsonPayload, schema);
+      assertThat(record.get("f_union")).isInstanceOf(GenericData.Record.class);
+      var innerRec = (GenericData.Record) record.get("f_union");
+      assertThat(innerRec.get("f_union")).isEqualTo(123);
+    }
+
+    @Test
+    void mapField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "long_map",
+                     "type": {
+                       "type": "map",
+                       "values" : "long",
+                       "default": {}
+                     }
+                   },
+                   {
+                     "name": "string_map",
+                     "type": {
+                       "type": "map",
+                       "values" : "string",
+                       "default": {}
+                     }
+                   },
+                   {
+                     "name": "self_ref_map",
+                     "type": {
+                       "type": "map",
+                       "values" : "TestAvroRecord",
+                       "default": {}
+                     }
+                   }
+                 ]
+              }"""
+      );
+
+      String jsonPayload = """
+          {
+            "long_map": {
+              "k1": 123,
+              "k2": 456
+            },
+            "string_map": {
+              "k3": "s1",
+              "k4": "s2"
+            },
+            "self_ref_map": {
+              "k5" : {
+                "long_map": { "_k1": 222 },
+                "string_map": { "_k2": "_s1" }
+              }
+            }
+          }
+          """;
+
+      var record = (GenericData.Record) convertJsonToAvro(jsonPayload, schema);
+      assertThat(record.get("long_map"))
+          .isEqualTo(Map.of("k1", 123L, "k2", 456L));
+      assertThat(record.get("string_map"))
+          .isEqualTo(Map.of("k3", "s1", "k4", "s2"));
+      assertThat(record.get("self_ref_map"))
+          .isNotNull();
+
+      Map<String, Object> selfRefMapField = (Map<String, Object>) record.get("self_ref_map");
+      assertThat(selfRefMapField)
+          .hasSize(1)
+          .hasEntrySatisfying("k5", v -> {
+            assertThat(v).isInstanceOf(GenericData.Record.class);
+            var innerRec = (GenericData.Record) v;
+            assertThat(innerRec.get("long_map"))
+                .isEqualTo(Map.of("_k1", 222L));
+            assertThat(innerRec.get("string_map"))
+                .isEqualTo(Map.of("_k2", "_s1"));
+          });
+    }
+
+    @Test
+    void arrayField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "f_array",
+                     "type": {
+                        "type": "array",
+                        "items" : "string",
+                        "default": []
+                      }
+                   }
+                 ]
+              }"""
+      );
+
+      String jsonPayload = """
+          {
+            "f_array": [ "e1", "e2" ]
+          }
+          """;
+
+      var record = (GenericData.Record) convertJsonToAvro(jsonPayload, schema);
+      assertThat(record.get("f_array")).isEqualTo(List.of("e1", "e2"));
+    }
+
+    @Test
+    void logicalTypesField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "lt_date",
+                     "type": { "type": "int", "logicalType": "date" }
+                   },
+                   {
+                     "name": "lt_uuid",
+                     "type": { "type": "string", "logicalType": "uuid" }
+                   },
+                   {
+                     "name": "lt_decimal",
+                     "type": { "type": "bytes", "logicalType": "decimal", "precision": 22, "scale":10 }
+                   },
+                   {
+                     "name": "lt_time_millis",
+                     "type": { "type": "int", "logicalType": "time-millis"}
+                   },
+                   {
+                     "name": "lt_time_micros",
+                     "type": { "type": "long", "logicalType": "time-micros"}
+                   },
+                   {
+                     "name": "lt_timestamp_millis",
+                     "type": { "type": "long", "logicalType": "timestamp-millis" }
+                   },
+                   {
+                     "name": "lt_timestamp_micros",
+                     "type": { "type": "long", "logicalType": "timestamp-micros" }
+                   },
+                   {
+                     "name": "lt_local_timestamp_millis",
+                     "type": { "type": "long", "logicalType": "local-timestamp-millis" }
+                   },
+                   {
+                     "name": "lt_local_timestamp_micros",
+                     "type": { "type": "long", "logicalType": "local-timestamp-micros" }
+                   }
+                 ]
+              }"""
+      );
+
+      String jsonPayload = """
+          {
+            "lt_date":"1991-08-14",
+            "lt_decimal": 2.1617413862327545E11,
+            "lt_time_millis": "10:15:30.001",
+            "lt_time_micros": "10:15:30.123456",
+            "lt_uuid": "a37b75ca-097c-5d46-6119-f0637922e908",
+            "lt_timestamp_millis": "2007-12-03T10:15:30.123Z",
+            "lt_timestamp_micros": "2007-12-13T10:15:30.123456Z",
+            "lt_local_timestamp_millis": "2017-12-03T10:15:30.123",
+            "lt_local_timestamp_micros": "2017-12-13T10:15:30.123456"
+          }
+          """;
+
+      var converted = convertJsonToAvro(jsonPayload, schema);
+      assertThat(converted).isInstanceOf(GenericData.Record.class);
+
+      var record = (GenericData.Record) converted;
+
+      assertThat(record.get("lt_date"))
+          .isEqualTo(LocalDate.of(1991, 8, 14));
+      assertThat(record.get("lt_decimal"))
+          .isEqualTo(new BigDecimal("2.1617413862327545E11"));
+      assertThat(record.get("lt_time_millis"))
+          .isEqualTo(LocalTime.parse("10:15:30.001"));
+      assertThat(record.get("lt_time_micros"))
+          .isEqualTo(LocalTime.parse("10:15:30.123456"));
+      assertThat(record.get("lt_timestamp_millis"))
+          .isEqualTo(Instant.parse("2007-12-03T10:15:30.123Z"));
+      assertThat(record.get("lt_timestamp_micros"))
+          .isEqualTo(Instant.parse("2007-12-13T10:15:30.123456Z"));
+      assertThat(record.get("lt_local_timestamp_millis"))
+          .isEqualTo(LocalDateTime.parse("2017-12-03T10:15:30.123"));
+      assertThat(record.get("lt_local_timestamp_micros"))
+          .isEqualTo(LocalDateTime.parse("2017-12-13T10:15:30.123456"));
+    }
+  }
+
+  // checking conversion of KafkaAvroDeserializer output to JsonNode
+  @Nested
+  class FromAvroToJson {
+
+    @Test
+    void primitiveRoot() {
+      assertThat(convertAvroToJson("str", createSchema("\"string\"")))
+          .isEqualTo(new TextNode("str"));
+
+      assertThat(convertAvroToJson(123, createSchema("\"int\"")))
+          .isEqualTo(new IntNode(123));
+
+      assertThat(convertAvroToJson(123L, createSchema("\"long\"")))
+          .isEqualTo(new LongNode(123));
+
+      assertThat(convertAvroToJson(123.1F, createSchema("\"float\"")))
+          .isEqualTo(new FloatNode(123.1F));
+
+      assertThat(convertAvroToJson(123.1, createSchema("\"double\"")))
+          .isEqualTo(new DoubleNode(123.1));
+
+      assertThat(convertAvroToJson(true, createSchema("\"boolean\"")))
+          .isEqualTo(BooleanNode.valueOf(true));
+
+      assertThat(convertAvroToJson(ByteBuffer.wrap(Longs.toByteArray(123L)), createSchema("\"bytes\"")))
+          .isEqualTo(new TextNode(new String(Longs.toByteArray(123L), StandardCharsets.ISO_8859_1)));
+    }
+
+    @SneakyThrows
+    @Test
+    void primitiveTypedFields() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "f_int",
+                     "type": "int"
+                   },
+                   {
+                     "name": "f_long",
+                     "type": "long"
+                   },
+                   {
+                     "name": "f_string",
+                     "type": "string"
+                   },
+                   {
+                     "name": "f_boolean",
+                     "type": "boolean"
+                   },
+                   {
+                     "name": "f_float",
+                     "type": "float"
+                   },
+                   {
+                     "name": "f_double",
+                     "type": "double"
+                   },
+                   {
+                     "name": "f_enum",
+                     "type" : {
+                      "type": "enum",
+                      "name": "Suit",
+                      "symbols" : ["SPADES", "HEARTS", "DIAMONDS", "CLUBS"]
+                     }
+                   },
+                   {
+                     "name" : "f_fixed",
+                     "type" : { "type" : "fixed" ,"size" : 8, "name": "long_encoded" }
+                   },
+                   {
+                     "name" : "f_bytes",
+                     "type": "bytes"
+                   }
+                 ]
+              }"""
+      );
+
+      byte[] fixedFieldValue = Longs.toByteArray(1234L);
+      byte[] bytesFieldValue = Longs.toByteArray(2345L);
+
+      GenericData.Record inputRecord = new GenericData.Record(schema);
+      inputRecord.put("f_int", 123);
+      inputRecord.put("f_long", 4294967294L);
+      inputRecord.put("f_string", "string here");
+      inputRecord.put("f_boolean", true);
+      inputRecord.put("f_float", 123.1f);
+      inputRecord.put("f_double", 123456.123456);
+      inputRecord.put("f_enum", new GenericData.EnumSymbol(schema.getField("f_enum").schema(), "SPADES"));
+      inputRecord.put("f_fixed", new GenericData.Fixed(schema.getField("f_fixed").schema(), fixedFieldValue));
+      inputRecord.put("f_bytes", ByteBuffer.wrap(bytesFieldValue));
+
+      String expectedJson = """
+          {
+            "f_int": 123,
+            "f_long": 4294967294,
+            "f_string": "string here",
+            "f_boolean": true,
+            "f_float": 123.1,
+            "f_double": 123456.123456,
+            "f_enum": "SPADES",
+            "f_fixed": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\u0004Ò",
+            "f_bytes": "\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\t)"
+          }
+          """;
+
+      assertJsonsEqual(expectedJson, convertAvroToJson(inputRecord, schema));
+    }
+
+    @Test
+    void logicalTypesField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "lt_date",
+                     "type": { "type": "int", "logicalType": "date" }
+                   },
+                   {
+                     "name": "lt_uuid",
+                     "type": { "type": "string", "logicalType": "uuid" }
+                   },
+                   {
+                     "name": "lt_decimal",
+                     "type": { "type": "bytes", "logicalType": "decimal", "precision": 22, "scale":10 }
+                   },
+                   {
+                     "name": "lt_time_millis",
+                     "type": { "type": "int", "logicalType": "time-millis"}
+                   },
+                   {
+                     "name": "lt_time_micros",
+                     "type": { "type": "long", "logicalType": "time-micros"}
+                   },
+                   {
+                     "name": "lt_timestamp_millis",
+                     "type": { "type": "long", "logicalType": "timestamp-millis" }
+                   },
+                   {
+                     "name": "lt_timestamp_micros",
+                     "type": { "type": "long", "logicalType": "timestamp-micros" }
+                   },
+                   {
+                     "name": "lt_local_timestamp_millis",
+                     "type": { "type": "long", "logicalType": "local-timestamp-millis" }
+                   },
+                   {
+                     "name": "lt_local_timestamp_micros",
+                     "type": { "type": "long", "logicalType": "local-timestamp-micros" }
+                   }
+                 ]
+              }"""
+      );
+
+      GenericData.Record inputRecord = new GenericData.Record(schema);
+      inputRecord.put("lt_date", LocalDate.of(1991, 8, 14));
+      inputRecord.put("lt_uuid", UUID.fromString("a37b75ca-097c-5d46-6119-f0637922e908"));
+      inputRecord.put("lt_decimal", new BigDecimal("2.16"));
+      inputRecord.put("lt_time_millis", LocalTime.parse("10:15:30.001"));
+      inputRecord.put("lt_time_micros", LocalTime.parse("10:15:30.123456"));
+      inputRecord.put("lt_timestamp_millis", Instant.parse("2007-12-03T10:15:30.123Z"));
+      inputRecord.put("lt_timestamp_micros", Instant.parse("2007-12-13T10:15:30.123456Z"));
+      inputRecord.put("lt_local_timestamp_millis", LocalDateTime.parse("2017-12-03T10:15:30.123"));
+      inputRecord.put("lt_local_timestamp_micros", LocalDateTime.parse("2017-12-13T10:15:30.123456"));
+
+      String expectedJson = """
+          {
+            "lt_date":"1991-08-14",
+            "lt_uuid": "a37b75ca-097c-5d46-6119-f0637922e908",
+            "lt_decimal": 2.16,
+            "lt_time_millis": "10:15:30.001",
+            "lt_time_micros": "10:15:30.123456",
+            "lt_timestamp_millis": "2007-12-03T10:15:30.123Z",
+            "lt_timestamp_micros": "2007-12-13T10:15:30.123456Z",
+            "lt_local_timestamp_millis": "2017-12-03T10:15:30.123",
+            "lt_local_timestamp_micros": "2017-12-13T10:15:30.123456"
+          }
+          """;
+
+      assertJsonsEqual(expectedJson, convertAvroToJson(inputRecord, schema));
+    }
+
+    @Test
+    void unionField() {
+      var schema = createSchema(
+          """
+               {
+                 "type": "record",
+                 "namespace": "com.test",
+                 "name": "TestAvroRecord",
+                 "fields": [
+                   {
+                     "name": "f_union",
+                     "type": [ "null", "int", "TestAvroRecord"]
+                   }
+                 ]
+              }"""
+      );
+
+      var r = new GenericData.Record(schema);
+      r.put("f_union", null);
+      assertJsonsEqual(" {}", convertAvroToJson(r, schema));
+
+      r = new GenericData.Record(schema);
+      r.put("f_union", 123);
+      assertJsonsEqual(" { \"f_union\" : { \"int\" : 123 } }", convertAvroToJson(r, schema));
+
+
+      r = new GenericData.Record(schema);
+      var innerRec = new GenericData.Record(schema);
+      innerRec.put("f_union", 123);
+      r.put("f_union", innerRec);
+      assertJsonsEqual(
+          " { \"f_union\" : { \"com.test.TestAvroRecord\" : { \"f_union\" : { \"int\" : 123 } } } }",
+          convertAvroToJson(r, schema)
+      );
+    }
+
+  }
+
+  private Schema createSchema(String schema) {
+    return new AvroSchema(schema).rawSchema();
+  }
+
+  @SneakyThrows
+  private void assertJsonsEqual(String expectedJson, JsonNode actual) {
+    var mapper = new JsonMapper();
+    assertThat(actual.toPrettyString())
+        .isEqualTo(mapper.readTree(expectedJson).toPrettyString());
+  }
+
+}