Bug: EventBridgeV2Envelope raises UnicodeDecodeError for application/octet-stream payloads that are not UTF-8 JSON #8666

import base64

from pydantic import BaseModel

from aws_lambda_powertools.utilities.data_classes import EventBridgeV2Event
from aws_lambda_powertools.utilities.parser import envelopes, parse


class Order(BaseModel):
    order_id: str


def octet_stream_event(payload: bytes) -> dict:
    return {
        "Data": base64.b64encode(payload).decode(),
        "Metadata": {},
        "SystemMetadata": {"ContentType": "application/octet-stream", "aws:DeliveryType": "LIVE"},
    }


for payload, model in ((b"\xff\xd8\xff\xe0JFIF", bytes), (b"hello world", bytes), (b"\xff\xd8\xff\xe0JFIF", Order)):
    event = octet_stream_event(payload)
    print(f"payload={payload!r} model={model.__name__}")
    print("  data class:", next(iter(EventBridgeV2Event(event).records)).data)
    try:
        print("  parser    :", parse(event=event, model=model, envelope=envelopes.EventBridgeV2Envelope))
    except Exception as exc:
        print(f"  parser    : {type(exc).__module__}.{type(exc).__name__}: {str(exc).splitlines()[0]}")

Output of the snippet on develop:

payload=b'\xff\xd8\xff\xe0JFIF' model=bytes
  data class: b'\xff\xd8\xff\xe0JFIF'
  parser    : builtins.UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte
payload=b'hello world' model=bytes
  data class: b'hello world'
  parser    : pydantic_core._pydantic_core.ValidationError: 1 validation error for bytes
payload=b'\xff\xd8\xff\xe0JFIF' model=Order
  data class: b'\xff\xd8\xff\xe0JFIF'
  parser    : builtins.UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte