checktheroads-hyperglass/hyperglass/exceptions.py

"""Custom exceptions for hyperglass."""

# Standard Library Imports
import json as _json

# Project Imports
from hyperglass.util import log


class HyperglassError(Exception):
    """hyperglass base exception."""

    def __init__(self, message="", alert="warning", keywords=None):
        """Initialize the hyperglass base exception class.

        Keyword Arguments:
            message {str} -- Error message (default: {""})
            alert {str} -- Error severity (default: {"warning"})
            keywords {list} -- 'Important' keywords (default: {None})
        """
        self._message = message
        self._alert = alert
        self._keywords = keywords or []
        if self._alert == "warning":
            log.error(repr(self))
        elif self._alert == "danger":
            log.critical(repr(self))
        else:
            log.info(repr(self))

    def __str__(self):
        """Return the instance's error message.

        Returns:
            {str} -- Error Message
        """
        return self._message

    def __repr__(self):
        """Return the instance's severity & error message in a string.

        Returns:
            {str} -- Error message with code
        """
        return f"[{self.alert.upper()}] {self._message}"

    def dict(self):
        """Return the instance's attributes as a dictionary.

        Returns:
            {dict} -- Exception attributes in dict
        """
        return {
            "message": self._message,
            "alert": self._alert,
            "keywords": self._keywords,
        }

    def json(self):
        """Return the instance's attributes as a JSON object.

        Returns:
            {str} -- Exception attributes as JSON
        """
        return _json.dumps(self.__dict__())

    @property
    def message(self):
        """Return the instance's `message` attribute.

        Returns:
            {str} -- Error Message
        """
        return self._message

    @property
    def alert(self):
        """Return the instance's `alert` attribute.

        Returns:
            {str} -- Alert name
        """
        return self._alert

    @property
    def keywords(self):
        """Return the instance's `keywords` attribute.

        Returns:
            {list} -- Keywords List
        """
        return self._keywords


class _UnformattedHyperglassError(HyperglassError):
    """Base exception class for freeform error messages."""

    _alert = "warning"

    def __init__(self, unformatted_msg="", alert=None, **kwargs):
        """Format error message with keyword arguments.

        Keyword Arguments:
            message {str} -- Error message (default: {""})
            alert {str} -- Error severity (default: {"warning"})
            keywords {list} -- 'Important' keywords (default: {None})
        """
        self._message = unformatted_msg.format(**kwargs)
        self._alert = alert or self._alert
        self._keywords = list(kwargs.values())
        super().__init__(
            message=self._message, alert=self._alert, keywords=self._keywords
        )


class _PredefinedHyperglassError(HyperglassError):
    _message = "undefined"
    _alert = "warning"

    def __init__(self, alert=None, **kwargs):
        self._fmt_msg = self._message.format(**kwargs)
        self._alert = alert or self._alert
        self._keywords = list(kwargs.values())
        super().__init__(
            message=self._fmt_msg, alert=self._alert, keywords=self._keywords
        )


class ConfigError(_UnformattedHyperglassError):
    """Raised for generic user-config issues."""


class ConfigInvalid(_PredefinedHyperglassError):
    """Raised when a config item fails type or option validation."""

    _message = 'The value field "{field}" is invalid: {error_msg}'


class ConfigMissing(_PredefinedHyperglassError):
    """Raised when a required config file or item is missing or undefined."""

    _message = (
        "{missing_item} is missing or undefined and is required to start "
        "hyperglass. Please consult the installation documentation."
    )


class ScrapeError(_UnformattedHyperglassError):
    """Raised when a scrape/netmiko error occurs."""

    _alert = "danger"


class AuthError(_UnformattedHyperglassError):
    """Raised when authentication to a device fails."""

    _alert = "danger"


class RestError(_UnformattedHyperglassError):
    """Raised upon a rest API client error."""

    _alert = "danger"


class DeviceTimeout(_UnformattedHyperglassError):
    """Raised when the connection to a device times out."""

    _alert = "danger"


class InputInvalid(_UnformattedHyperglassError):
    """Raised when input validation fails."""


class InputNotAllowed(_UnformattedHyperglassError):
    """Raised when input validation fails due to a configured check."""


class ResponseEmpty(_UnformattedHyperglassError):
    """Raised when hyperglass can connect to the device but the response is empty."""


class UnsupportedDevice(_UnformattedHyperglassError):
    """Raised when an input NOS is not in the supported NOS list."""