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KafkaMessage

faststream.kafka.message.KafkaMessage #

KafkaMessage(
    *args: Any, consumer: ConsumerProtocol, **kwargs: Any
)

Bases: StreamMessage[Union['ConsumerRecord[Any, Any]', tuple['ConsumerRecord[Any, Any]', ...]]]

Represents a Kafka message in the FastStream framework.

This class extends StreamMessage and is specialized for handling Kafka ConsumerRecord objects.

Source code in faststream/kafka/message.py 
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def __init__(self, *args: Any, consumer: ConsumerProtocol, **kwargs: Any) -> None:
    super().__init__(*args, **kwargs)
    self.consumer = consumer
    self.committed = AckStatus.ACKED

consumer instance-attribute #

consumer = consumer

committed instance-attribute #

committed = AckStatus.ACKED

raw_headers property #

raw_headers: dict[str, bytes | None]

Original header bytes, or the first message's headers for a batch.

batch_raw_headers property #

batch_raw_headers: list[dict[str, bytes | None]]

Original header bytes for every batch message; empty for a single message.

raw_message instance-attribute #

raw_message = raw_message

body instance-attribute #

body = body

reply_to instance-attribute #

reply_to = reply_to

content_type instance-attribute #

content_type = content_type

source_type instance-attribute #

source_type = source_type

headers instance-attribute #

headers = headers or {}

batch_headers instance-attribute #

batch_headers = batch_headers or []

path instance-attribute #

path = path or {}

correlation_id instance-attribute #

correlation_id = correlation_id or str(uuid4())

message_id instance-attribute #

message_id = message_id or self.correlation_id

processed instance-attribute #

processed = False

set_decoder #

set_decoder(decoder: AsyncCallable) -> None
Source code in faststream/message/message.py 
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def set_decoder(self, decoder: "AsyncCallable") -> None:
    self.__decoder = decoder

clear_cache #

clear_cache() -> None
Source code in faststream/message/message.py 
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def clear_cache(self) -> None:
    self.__decoded_caches.clear()

decode async #

decode() -> Optional[Any]

Serialize the message by lazy decoder.

Returns a cache after first usage. To prevent such behavior, please call message.clear_cache() after message.body changes.

Source code in faststream/message/message.py 
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async def decode(self) -> Optional["Any"]:
    """Serialize the message by lazy decoder.

    Returns a cache after first usage. To prevent such behavior, please call
    `message.clear_cache()` after `message.body` changes.
    """
    assert self.__decoder, "You should call `set_decoder()` method first."

    if (
        result := self.__decoded_caches.get(self.__decoder, _NOT_CACHED)
    ) is _NOT_CACHED:
        result = self.__decoded_caches[self.__decoder] = await self.__decoder(self)

    return result

ack async #

ack() -> None
Source code in faststream/message/message.py 
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async def ack(self) -> None:
    if self.committed is None:
        self.committed = AckStatus.ACKED

nack async #

nack() -> None
Source code in faststream/message/message.py 
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async def nack(self) -> None:
    if self.committed is None:
        self.committed = AckStatus.NACKED

reject async #

reject() -> None
Source code in faststream/message/message.py 
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async def reject(self) -> None:
    if self.committed is None:
        self.committed = AckStatus.REJECTED