Thanks Dian. It worked for me

Regards,
Zerah

On Wed, May 19, 2021, 5:14 PM Dian Fu <dian0511...@gmail.com> wrote:

> Hi Zerah,
>
> You could try to replace
> ```
> value_schema = avro.schema.parse(<reader schema goes here>)
> ```
>
> with the following code:
> ```
> JSchemaParser = get_gateway().jvm.org.apache.avro.Schema.Parser
> value_schema = JSchemaParser().parse(value_schema_str)
> ```
>
> The reason is that ```value_schema = avro.schema.parse(<reader schema goes
> here>) ``` will create a Python object instead of Java object.
>
> Regards,
> Dian
>
> 2021年5月19日 下午5:23,Zerah J <connectze...@gmail.com> 写道:
>
> Hi Dian,
>
> Type of value_schema is <*class 'avro.schema.RecordSchema*'>
>
> I have only a Json schema string and schema registry url. Please find
> below snippet :
>
> import avro.schema
>
> value_schema_str = """
>     {
>       "namespace": "com.nextgen.customer",
>       "type": "record",
>       "name": "employee",
>       "doc": "Customer Details Value Schema.",
>       "fields": [
>         {
>           "doc": "String Value",
>           "name": "emp_name",
>           "type": "string"
>         },
>         {
>           "doc": "String Value",
>           "name": "emp_id",
>           "type": "string"
>         }
>       ]
>     }
> value_schema = avro.schema.parse(value_schema_str)
> schema_url = "http://host:port";
>
>
> How can I create Java Schema object from this schema string and pass it
> from python method ?
>
>
> Regards,
> Zerah
>
>
> On Wed, May 19, 2021 at 1:57 PM Dian Fu <dian0511...@gmail.com> wrote:
>
>> Hi Zerah,
>>
>> What’s the type of value_schema? It should be a Java object of type
>> Schema. From the exception, it seems that it’s a class instead of object.
>> Is this true?
>>
>> Regards,
>> Dian
>>
>> 2021年5月19日 下午3:41,Zerah J <connectze...@gmail.com> 写道:
>>
>> Hi Dian,
>>
>> Thanks for your suggestion.
>>
>> I tried to invoke  ConfluentRegistryAvroDeserializationSchema.forGeneric
>> method from Python. But it's not working. Kindly check the code snippet
>> below :
>>
>> class MyAvroRowDeserializationSchema(DeserializationSchema):
>>
>>     def __init__(self, record_class: str = None, avro_schema_string:
>> schema = None, url: str = None):
>>             JConfluentAvroRowDeserializationSchema = get_gateway().jvm \
>>
>> .org.apache.flink.formats.avro.registry.confluent.ConfluentRegistryAvroDeserializationSchema
>>             j_deserialization_schema =
>> JConfluentAvroRowDeserializationSchema.forGeneric(avro_schema_string, url)
>>
>>     super(MyAvroRowDeserializationSchema,
>> self).__init__(j_deserialization_schema)
>>
>>
>> FlinkKafkaConsumer is now invoked as below using
>> MyAvroRowDeserializationSchema :
>>
>> value_schema = avro.schema.parse(<reader schema goes here>)
>> schema_url = "http://host:port";
>> deserialization_schema =
>> MyAvroRowDeserializationSchema(avro_schema_string=value_schema,url=schema_url)
>> kafka_source = FlinkKafkaConsumer(
>>         topics='my_topic',
>>         deserialization_schema=deserialization_schema,
>>         properties={'bootstrap.servers': 'host:port', 'group.id':
>> 'test_group'})
>>
>> I'm getting the below error :
>>
>> Traceback (most recent call last):
>>   File "flinkKafkaAvro.py", line 70, in datastream_api_demo
>>     deserialization_schema =
>> MyAvroRowDeserializationSchema(avro_schema_string=value_schema,url=schema_url)
>>   File "test_env/tests/SerializeAvroSchema.py", line 52, in __init__
>>     j_deserialization_schema =
>> JConfluentAvroRowDeserializationSchema.forGeneric(avro_schema_string, url)
>>   File
>> "test_env/venv/lib64/python3.7/site-packages/py4j/java_gateway.py", line
>> 1277, in __call__
>>     args_command, temp_args = self._build_args(*args)
>>   File
>> "test_env/venv/lib64/python3.7/site-packages/py4j/java_gateway.py", line
>> 1247, in _build_args
>>     [get_command_part(arg, self.pool) for arg in new_args])
>>   File
>> "test_env/venv/lib64/python3.7/site-packages/py4j/java_gateway.py", line
>> 1247, in <listcomp>
>>     [get_command_part(arg, self.pool) for arg in new_args])
>>   File "test_env/venv/lib64/python3.7/site-packages/py4j/protocol.py",
>> line 298, in get_command_part
>>     command_part = REFERENCE_TYPE + parameter._get_object_id()
>> AttributeError: 'RecordSchema' object has no attribute '_get_object_id'
>>
>>
>>
>> Please suggest how this method should be called. Here the schema used is
>> avro schema.
>>
>> Regards,
>> Zerah
>>
>> On Mon, May 17, 2021 at 3:17 PM Dian Fu <dian0511...@gmail.com> wrote:
>>
>>> Hi Zerah,
>>>
>>> I guess you could provide a Python implementation for
>>> ConfluentRegistryAvroDeserializationSchema if needed. It’s just a wrapper
>>> for the Java implementation and so it’s will be very easy to implement. You
>>> could take a look at AvroRowDeserializationSchema [1] as an example.
>>>
>>> Regards,
>>> Dian
>>>
>>> [1]
>>> https://github.com/apache/flink/blob/release-1.13/flink-python/pyflink/common/serialization.py#L303
>>>
>>> > 2021年5月17日 下午5:35,Zerah J <connectze...@gmail.com> 写道:
>>> >
>>> > Hi,
>>> >
>>> > I have below use case
>>> >
>>> > 1. Read streaming data from Kafka topic using Flink Python API
>>> > 2. Apply transformations on the data stream
>>> > 3. Write back to different kafka topics based on the incoming data
>>> >
>>> > Input data is coming from Confluent Avro Producer. By using the
>>> existing pyflink.common.serialization.AvroRowDeserializationSchema, I'm
>>> unable to deserialize the data.
>>> >
>>> > Please help to process the data as
>>> ConfluentRegistryAvroDeserializationSchema is not available in the Python
>>> API.
>>> >
>>> > Regards,
>>> > Zerah
>>>
>>>
>>
>

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