App.distro_xxx: Move properties to Distro.xxx

Commit a19679fec reverted the first attempt to make AsyncSSH reuse one connection during an instance lifetime. That failed because a lot of distribution-specific properties were filled in a new event loop thread started by AsyncRunner, and AsyncSSH didn't like that.

This commit is the first part of the solution: Move those properties from the App class to the Distro class, and load the Distro class in an async loader. As soon as it's instantiated, it can provide all its properties without cluttering the code with async keywords.

Signed-off-by: Jan Lindemann <jan@janware.com>
This commit is contained in:
Jan Lindemann 2026-04-18 12:08:00 +02:00
commit aa7275f426
7 changed files with 241 additions and 231 deletions

View file

@ -3,32 +3,86 @@
from __future__ import annotations
from typing import TYPE_CHECKING
from functools import cached_property
if TYPE_CHECKING:
import Iterable
import abc, importlib
import abc, importlib, re
from .ExecContext import ExecContext
from .base import Result
from .base import Result, InputMode
from .Package import Package
from .log import *
class Distro(abc.ABC):
def __init__(self, ec: ExecContext):
def __init__(self, ec: ExecContext, id: str|None=None, os_release_str: str|None=None):
assert ec is not None
assert id is not None
self.__exec_context = ec
self.__os_release_str: str|None = os_release_str
self.__id: str|None = None
def __set_id(self, id: str) -> None:
self.__id = id
# Names that can be used by code outside this class to retrieve
# distribution properties by
# getattr(instance, name.replace('-', '_'))
macro_names = [
'os',
'id',
'name',
'codename',
'gnu-triplet',
'os-cascade',
'os-release',
'pkg-ext',
]
# == Load
@classmethod
def instantiate(cls, distro_id: str, *args, **kwargs):
backend_id = distro_id.lower().replace('-', '_')
async def read_os_release_str(cls, ec: ExecContext) -> None:
release_file = '/etc/os-release'
try:
result = await ec.get(release_file, throw=True)
ret = result.stdout.decode().strip()
except Exception as e:
log(INFO, f'Failed to read {release_file} ({str(e)}), falling back to uname')
result = await ec.run(
['uname', '-s'],
throw=False,
cmd_input=InputMode.NonInteractive
)
if result.status != 0:
log(ERR, f'/etc/os-release and uname both failed, the latter with exit status {result.status}')
raise
uname = result.decode().stdout.strip().lower()
ret = f'ID={uname}\nVERSION_CODENAME=unknown'
return ret
@classmethod
def parse_os_release_field(self, key: str, os_release_str: str, throw: bool=False) -> str:
m = re.search(r'^\s*' + key + r'\s*=\s*("?)([^"\n]+)\1\s*$', os_release_str, re.MULTILINE)
if m is None:
if throw:
raise Exception(f'Could not read "{key}=" from /etc/os-release')
return None
return m.group(2)
@classmethod
def parse_os_release_field_id(cls, os_release_str: str, throw: bool=False) -> str:
ret = cls.parse_os_release_field('ID', os_release_str, throw=throw)
match ret:
case 'opensuse-tumbleweed':
return 'suse'
return ret
@classmethod
async def instantiate(cls, ec: ExecContext, *args, id: str|None=None, os_release_str: str|None=None, **kwargs):
if id is None:
os_release_str = await cls.read_os_release_str(ec)
id = cls.parse_os_release_field_id(os_release_str, throw=True)
backend_id = id.lower().replace('-', '_')
match backend_id:
case 'ubuntu' | 'raspbian' | 'kali':
backend_id = 'debian'
@ -43,16 +97,172 @@ class Distro(abc.ABC):
log(ERR, f'Failed to import Distro module {module_path} ({str(e)})')
raise
cls = getattr(module, 'Distro')
ret = cls(*args, **kwargs)
ret.__set_id(backend_id)
ret = cls(ec, *args, id=id, os_release_str=os_release_str, **kwargs)
return ret
def os_release_field(self, key: str, throw: bool=False) -> str:
return self.parse_os_release_field(key, self.os_release_str, throw)
async def cache(self) -> None:
if self.__os_release_str is None:
self.__os_release_str = await self.read_os_release_str(self.__exec_context)
@cached_property
def os_cascade(self) -> list[str]:
def __append(entry: str):
if not entry in ret:
ret.append(entry)
ret = [ 'os' ]
match self.id:
case 'centos':
__append('linux')
__append('pkg-rpm')
__append('pm-yum')
__append('redhat')
__append('rhel')
case 'fedora' | 'rhel':
__append('linux')
__append('pkg-rpm')
__append('pm-yum')
__append('redhat')
case 'suse':
__append('linux')
__append('pkg-rpm')
__append('pm-zypper')
case 'kali' | 'raspbian':
__append('linux')
__append('pkg-debian')
__append('pm-apt')
__append('debian')
case 'ubuntu':
__append('linux')
__append('pkg-debian')
__append('pm-apt')
case 'archlinux':
__append('linux')
__append('pkg-pm')
__append('pm-pacman')
os = self.os
name = re.sub(r'-.*', '', os)
series = os
rx = re.compile(r'\.[0-9]+$')
while True:
n = re.sub(rx, '', series)
if n == series:
break
ret.append(n)
series = n
__append(name)
__append(os)
__append(self.id)
# e.g. os, linux, suse, suse-tumbleweed
return ret
@cached_property
def cascade(self) -> str:
return ' '.join(self.os_cascade)
@property
def os_release_str(self) -> str:
if self.__os_release_str is None:
raise Exception(f'Tried to access OS release from an incompletely loaded Distro instance. Call reacache() before')
return self.__os_release_str
@cached_property
def name(self) -> str:
return self.os_release_field('NAME', throw=True)
@cached_property
def id(self) -> str:
return self.parse_os_release_field_id(self.__os_release_str, throw=True)
@cached_property
def codename(self) -> str:
match self.id:
case 'suse':
return self.os_release_field('ID', throw=True).split('-')[1]
case 'kali':
return self.os_release_field('VERSION_CODENAME', throw=True).split('-')[1]
case _:
return self.os_release_field('VERSION_CODENAME', throw=True)
raise NotImplementedError(f'Can\'t determine code name from distribution ID {self.id}')
@cached_property
def os(self) -> str:
return self.id + '-' + self.codename
@cached_property
def pkg_ext(self) -> str:
for entry in self.os_cascade():
ret = entry.replace('pkg-', '')
if ret != entry:
return ret
raise RuntimeError(f'No package extension in found in {self.os_cascade}')
@cached_property
def gnu_triplet(self) -> str:
import sysconfig
import shutil
import subprocess
# Best: GNU host triplet Python was built for
for key in ("HOST_GNU_TYPE", "BUILD_GNU_TYPE"): # BUILD_GNU_TYPE can exist too
ret = sysconfig.get_config_var(key)
if isinstance(ret, str) and ret:
return ret
# Common on Debian/Ubuntu: multiarch component (often looks like a triplet)
ret = sysconfig.get_config_var("MULTIARCH")
if isinstance(ret, str) and ret:
return ret
# Sometimes exposed (privately) by CPython
ret = getattr(sys.implementation, "_multiarch", None)
if isinstance(ret, str) and ret:
return ret
# Last resort: ask the system compiler
for cc in ("gcc", "cc", "clang"):
path = shutil.which(cc)
if not path:
continue
try:
ret = subprocess.check_output([path, "-dumpmachine"], text=True, stderr=subprocess.DEVNULL).strip()
if ret:
return ret
except Exception:
pass
raise RuntimeError('Failed to get GNU triplet from running machine')
@classmethod
def macros(cls) -> list[str]:
return ['%%{' + name + '}' for name in cls.macro_names]
def expand_macros(self, fmt: str|Iterable) -> str|Iterable:
if not isinstance(fmt, str):
ret: list[str] = []
for entry in fmt:
ret.append(self.expand_macros(entry))
return ret
ret = fmt
for macro in re.findall("%{([A-Za-z_-]+)}", fmt):
try:
name = macro.replace('-', '_')
val = getattr(self, name)
patt = r'%{' + macro + r'}'
if ret.find(patt) == -1:
continue
ret = ret.replace(patt, val)
except Exception as e:
log(ERR, f'Failed to expand macro "{macro}" inside "{fmt}": {str(e)}')
raise
return ret
# == Convenience methods
@property
def id(self) -> str:
return self.__id
@property
def ctx(self) -> ExecContext:
return self.__exec_context
@ -67,7 +277,7 @@ class Distro(abc.ABC):
def interactive(self) -> bool:
return self.__exec_context.interactive
# == Distribution specific methods
# == Distribution abstraction methods
# -- ref