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BatchParser

faststream.nats.parser.BatchParser #

BatchParser(*, pattern: str)

Bases: JsParser

A class to parse NATS batch messages.

Source code in faststream/nats/parser.py 
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def __init__(
    self,
    *,
    pattern: str,
) -> None:
    path_re, _ = compile_nats_wildcard(pattern)
    self._path_re = path_re

parse_batch async #

parse_batch(message: list[Msg]) -> StreamMessage[list[Msg]]
Source code in faststream/nats/parser.py 
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async def parse_batch(
    self,
    message: list["Msg"],
) -> "StreamMessage[list[Msg]]":
    body: list[bytes] = []
    batch_headers: list[dict[str, str]] = []

    if message:
        path = match_path(self._path_re, message[0].subject)

        for m in message:
            batch_headers.append(m.headers or {})
            body.append(m.data)

    else:
        path = {}

    headers = next(iter(batch_headers), {})

    return NatsBatchMessage(
        raw_message=message,
        body=body,
        path=path,
        headers=headers,
        batch_headers=batch_headers,
    )

decode_batch async #

decode_batch(
    msg: StreamMessage[list[Msg]],
) -> list[DecodedMessage]
Source code in faststream/nats/parser.py 
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async def decode_batch(
    self,
    msg: "StreamMessage[list[Msg]]",
) -> list["DecodedMessage"]:
    data: list[DecodedMessage] = []

    for m in msg.raw_message:
        one_msg = await self.parse_message(m)
        data.append(decode_message(one_msg))

    return data

decode_message async #

decode_message(msg: StreamMessage[Any]) -> DecodedMessage
Source code in faststream/nats/parser.py 
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async def decode_message(  # ruff: ignore[no-self-use]
    self,
    msg: "StreamMessage[Any]",
) -> "DecodedMessage":
    return decode_message(msg)

parse_message async #

parse_message(message: Msg) -> StreamMessage[Msg]
Source code in faststream/nats/parser.py 
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async def parse_message(
    self,
    message: "Msg",
) -> "StreamMessage[Msg]":
    path = match_path(self._path_re, message.subject)

    headers = message.header or {}

    return NatsMessage(
        raw_message=message,
        body=message.data,
        path=path,
        reply_to=headers.get("reply_to", ""),  # differ from core
        headers=headers,
        content_type=headers.get("content-type"),
        message_id=headers.get("message_id"),
        correlation_id=headers.get("correlation_id"),
    )