[Python] 직렬화/역직렬화 (Serialization/Deserialization)

Serialization/Deserialization

	Serialization
Object	-> <-	String (json) Byte Array (pickle)
	Deserialization

json module vs. pickle module

• json: object <-> text serialization format
• pickle: object <-> binary serialization format

Conversion (Python Object <-> JSON)

• dict <-> object
• list, tuple <-> array
• str <-> string
• int, float, int- & float-derived Enums <-> number
• True <-> true
• False <-> false
• None <-> null

Serialization

1. Python object to JSON formatted string

json.dumps(obj)

1. Python object to bytes-like object(bytes, bytearray, memoryview, …)

pickle.dumps(obj)

Deserialization

1. JSON formatted string to python object

json.loads(data)

1. Bytes-like object(bytes, bytearray, memoryview, …) to python object

pickle.loads(data)

Serialization in producer of kafka-python

• https://github.com/dpkp/kafka-python
• Python object -> JSON formatted string -> bytes-like object

producer = KafkaProducer(bootstrap_servers='my-kafka:9092', value_serializer=lambda v: json.dumps(v).encode('utf-8'))

@staticmethod
def send(value, key):
  producer.send('my-topic', value=value, key=key)

Deserialization in consumer of kafka-python

• bytes-like object -> JSON formatted string -> Python object

consumer = KafkaConsumer('my-topic',
                         group_id='my-consumer-group-id',
                         bootstrap_servers='my-kafka:9092',
                         value_deserializer=lambda m: json.loads(m.decode('utf-8')))
                         
@staticmethod
def subscribe():
  for msg in MyKafkaConsumer.consumer:
    print(msg.value)