packet_loss

Signature

faultcore.packet_loss(p: str)

Purpose

Injects probabilistic packet drops.

Parameters

• p: probability string with % or ppm suffix.

Defaults and validation

• % values must be between 0 and 100.

• ppm values must be between 0 and 1_000_000.

Example (UDP reliability test)

import faultcore


@faultcore.packet_loss("2%")
def send_datagrams(total: int) -> int:
    delivered = int(total * 0.98)
    return delivered


def test_udp_client_retries_under_loss() -> None:
    delivered = send_datagrams(1000)
    assert delivered < 1000