settings.py

import contextlib
from typing import Annotated

from pydantic import Field
from pydantic_settings import BaseSettings, SettingsConfigDict

ENVIRONMENT_PREFIX = "CF_TICK_"
"""
All environment variables are expected to be prefixed with this.
"""

ENV_CONDA_FORGE_ORG = ENVIRONMENT_PREFIX + "CONDA_FORGE_ORG"
"""
The environment variable used to set the `conda_forge_org` setting.
Note: This must match the field name in the `BotSettings` class.
"""

ENV_GRAPH_GITHUB_BACKEND_REPO = ENVIRONMENT_PREFIX + "GRAPH_GITHUB_BACKEND_REPO"
"""
The environment variable used to set the `graph_github_backend_repo` setting.
Note: This must match the field name in the `BotSettings` class.
"""

Fraction = Annotated[float, Field(ge=0.0, le=1.0)]


class BotSettings(BaseSettings):
    """
    The global settings for the bot.

    To configure a settings value, set the corresponding environment variable with the prefix `CF_TICK_`.
    For example, to set the `graph_github_backend_repo` setting, set the environment variable
    `CF_TICK_GRAPH_GITHUB_BACKEND_REPO`.

    To access the current settings object, please use the `settings()` function.

    Note: There still exists a significant amount of settings that are not yet exposed here.
    All new settings should go here, and the other ones should eventually be migrated.
    """

    model_config = SettingsConfigDict(env_prefix=ENVIRONMENT_PREFIX)

    conda_forge_org: str = Field("conda-forge", pattern=r"^[\w\.-]+$")
    """
    The GitHub organization containing all feedstocks. Default: "conda-forge".
    If you change the field name, you must also update the `ENV_CONDA_FORGE_ORG` constant.
    """

    graph_github_backend_repo: str = Field(
        "regro/cf-graph-countyfair", pattern=r"^[\w\.-]+/[\w\.-]+$"
    )
    """
    The GitHub repository to deploy to. Default: "regro/cf-graph-countyfair".
    If you change the field name, you must also update the `ENV_GRAPH_GITHUB_BACKEND_REPO` constant.
    """

    graph_repo_default_branch: str = "master"
    """
    The default branch of the graph_github_backend_repo repository.
    """

    @property
    def graph_github_backend_raw_base_url(self) -> str:
        """
        The base URL for the GitHub raw view of the graph_github_backend_repo repository.
        Example: https://github.com/regro/cf-graph-countyfair/raw/master.
        """
        return f"https://github.com/{self.graph_github_backend_repo}/raw/{self.graph_repo_default_branch}/"

    github_runner_debug: bool = Field(False, alias="RUNNER_DEBUG")
    """
    Whether we are executing within a GitHub Actions run with debug logging enabled. Default: False.
    This is set automatically by GitHub Actions.
    https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/store-information-in-variables#default-environment-variables
    """

    frac_update_upstream_versions: Fraction = 1.0
    """
    The fraction of feedstocks (randomly selected) to update in the update-upstream-versions job.
    This is currently only respected when running concurrently (via process pool), not in sequential mode.
    Therefore, you don't need to set this when debugging locally.
    """

    batch_size_update_upstream_versions_deploy: int = 10
    """The batch size used to push upstream version updates to the graph as they are found.
    """

    frac_make_graph: Fraction = 0.1
    """
    The fraction of feedstocks (randomly selected) to update in the make-graph job.
    In tests or when debugging, you probably need to set this to 1.0 to update all feedstocks.
    """

    frac_update_pr_json: Fraction = 0.25
    """
    The fraction of feedstocks (randomly selected) to update in the prs job.
    In tests or when debugging, you probably need to set this to 1.0 to update all feedstocks.
    """

    pull_request_reopen_window: float = 15 * 60.0
    """
    A pull request that is closed can be reopened if it is done so within this amount of time.
    Specified in seconds.
    """

    pr_refresh_age_days: float = 7.0
    """
    Number of days after which to refresh PR cache for 'clean' PRs to detect potential conflicts.
    Works around GitHub API bug #5150 where Last-Modified caching can hide merge conflicts.
    Set to 0 to always refresh.
    """


_use_settings_override: BotSettings | None = None
"""
If not None, the application should use this settings object instead of generating a new one.
"""


def settings() -> BotSettings:
    """Get the current settings object."""
    if _use_settings_override:
        return _use_settings_override.model_copy()  # prevent side-effects
    return BotSettings()


@contextlib.contextmanager
def use_settings(s: BotSettings | None):
    """
    Context manager that overrides the application settings with the values set in the provided settings object.
    The new settings are used within the context of the `with` statement.
    After exiting the context, the original settings are restored.

    DO NOT call this function within multithreading contexts, as it will override the settings for all threads,
    and lead to unpredictable behavior.

    Parameters
    ----------
    s
        The settings object to use. None stands for the default settings behavior. The default settings
        behavior reads the environment variables every time the settings are accessed.
    """
    global _use_settings_override

    old_settings = (
        _use_settings_override.model_copy() if _use_settings_override else None
    )
    _use_settings_override = s.model_copy() if s else None

    yield

    _use_settings_override = old_settings