airflow/metrics/base_stats_logger.py

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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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from __future__ import annotations

from airflow.metrics.protocols import DeltaType, Timer, TimerProtocol
from airflow.typing_compat import Protocol


class StatsLogger(Protocol):
    """This class is only used for TypeChecking (for IDEs, mypy, etc)."""

    @classmethod
    def incr(
        cls,
        stat: str,
        count: int = 1,
        rate: int | float = 1,
        *,
        tags: dict[str, str] | None = None,
    ) -> None:
        """Increment stat."""

    @classmethod
    def decr(
        cls,
        stat: str,
        count: int = 1,
        rate: int | float = 1,
        *,
        tags: dict[str, str] | None = None,
    ) -> None:
        """Decrement stat."""

    @classmethod
    def gauge(
        cls,
        stat: str,
        value: float,
        rate: int | float = 1,
        delta: bool = False,
        *,
        tags: dict[str, str] | None = None,
    ) -> None:
        """Gauge stat."""

    @classmethod
    def timing(
        cls,
        stat: str,
        dt: DeltaType | None,
        *,
        tags: dict[str, str] | None = None,
    ) -> None:
        """Stats timing."""

    @classmethod
    def timer(cls, *args, **kwargs) -> TimerProtocol:
        """Timer metric that can be cancelled."""
        raise NotImplementedError()


class NoStatsLogger:
    """If no StatsLogger is configured, NoStatsLogger is used as a fallback."""

    @classmethod
    def incr(cls, stat: str, count: int = 1, rate: int = 1, *, tags: dict[str, str] | None = None) -> None:
        """Increment stat."""

    @classmethod
    def decr(cls, stat: str, count: int = 1, rate: int = 1, *, tags: dict[str, str] | None = None) -> None:
        """Decrement stat."""

    @classmethod
    def gauge(
        cls,
        stat: str,
        value: int,
        rate: int = 1,
        delta: bool = False,
        *,
        tags: dict[str, str] | None = None,
    ) -> None:
        """Gauge stat."""

    @classmethod
    def timing(cls, stat: str, dt: DeltaType, *, tags: dict[str, str] | None = None) -> None:
        """Stats timing."""

    @classmethod
    def timer(cls, *args, **kwargs) -> TimerProtocol:
        """Timer metric that can be cancelled."""
        return Timer()