#
# Copyright 2021 Canonical Ltd.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License version 3 as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
"""Craft provider errors."""
import dataclasses
import shlex
import subprocess
from typing import List, Optional, Union
[docs]def details_from_command_error(
*,
cmd: List[str],
returncode: int,
stdout: Optional[Union[bytes, str]] = None,
stderr: Optional[Union[bytes, str]] = None,
) -> str:
"""Create a consistent ProviderError from command errors.
stdout and stderr, if provided, will be stringified using its object
representation. This method does not decode byte strings.
:param cmd: Command executed.
:param returncode: Command exit code.
:param stdout: Optional stdout to include.
:param stderr: Optional stderr to include.
:returns: Details string.
"""
cmd_string = shlex.join(cmd)
details = [
f"* Command that failed: {cmd_string!r}",
f"* Command exit code: {returncode}",
]
if stdout:
details.append(f"* Command output: {stdout!r}")
if stderr:
details.append(f"* Command standard error output: {stderr!r}")
return "\n".join(details)
[docs]def details_from_called_process_error(
error: subprocess.CalledProcessError,
) -> str:
"""Create a consistent ProviderError from command errors.
:param error: CalledProcessError.
:returns: Details string.
"""
return details_from_command_error(
cmd=error.cmd,
stdout=error.stdout,
stderr=error.stderr,
returncode=error.returncode,
)
[docs]@dataclasses.dataclass
class ProviderError(Exception):
"""Unexpected error.
:param brief: Brief description of error.
:param details: Detailed information.
:param resolution: Recommendation, if any.
"""
brief: str
details: Optional[str] = None
resolution: Optional[str] = None
def __str__(self) -> str:
parts = [self.brief]
if self.details:
parts.append(self.details)
if self.resolution:
parts.append(self.resolution)
return "\n".join(parts)