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NatsMessage

faststream.nats.message.NatsMessage #

NatsMessage(
    raw_message: MsgType,
    body: bytes | Any,
    *,
    headers: dict[str, Any] | None = None,
    reply_to: str = "",
    batch_headers: list[dict[str, Any]] | None = None,
    path: dict[str, Any] | None = None,
    content_type: str | None = None,
    correlation_id: str | None = None,
    message_id: str | None = None,
    source_type: SourceType = CONSUME,
)

Bases: StreamMessage[Msg]

A class to represent a NATS message.

Source code in faststream/message/message.py 
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def __init__(
    self,
    raw_message: "MsgType",
    body: bytes | Any,
    *,
    headers: dict[str, Any] | None = None,
    reply_to: str = "",
    batch_headers: list[dict[str, Any]] | None = None,
    path: dict[str, Any] | None = None,
    content_type: str | None = None,
    correlation_id: str | None = None,
    message_id: str | None = None,
    source_type: SourceType = SourceType.CONSUME,
) -> None:
    self.raw_message = raw_message
    self.body = body
    self.reply_to = reply_to
    self.content_type = content_type
    self.source_type = source_type

    self.headers = headers or {}
    self.batch_headers = batch_headers or []
    self.path = path or {}
    self.correlation_id = correlation_id or str(uuid4())
    self.message_id = message_id or self.correlation_id

    self.committed: AckStatus | None = None
    self.processed = False

    # Setup later
    self.__decoder: AsyncCallable | None = None
    self.__decoded_caches: dict[
        Any,
        Any,
    ] = {}  # Cache values between filters and tests

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

committed instance-attribute #

committed: AckStatus | None = None

processed instance-attribute #

processed = False

ack async #

ack() -> None
Source code in faststream/nats/message.py 
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async def ack(self) -> None:
    # Check `self.raw_message._ackd` instead of `self.committed`
    # to be compatible with `self.raw_message.ack()`
    if not self.raw_message._ackd:
        await self.raw_message.ack()
    await super().ack()

ack_sync async #

ack_sync() -> None
Source code in faststream/nats/message.py 
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async def ack_sync(self) -> None:
    if not self.raw_message._ackd:
        await self.raw_message.ack_sync()
    await super().ack()

nack async #

nack(delay: float | None = None) -> None
Source code in faststream/nats/message.py 
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async def nack(
    self,
    delay: float | None = None,
) -> None:
    if not self.raw_message._ackd:
        await self.raw_message.nak(delay=delay)
    await super().nack()

reject async #

reject() -> None
Source code in faststream/nats/message.py 
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async def reject(self) -> None:
    if not self.raw_message._ackd:
        await self.raw_message.term()
    await super().reject()

in_progress async #

in_progress() -> None
Source code in faststream/nats/message.py 
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async def in_progress(self) -> None:
    if not self.raw_message._ackd:
        await self.raw_message.in_progress()

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