"""Plugin utilities."""
import logging
from typing import List
from certbot import util
from certbot.compat import os
from certbot.compat.misc import STANDARD_BINARY_DIRS
logger = logging.getLogger(__name__)
[docs]def get_prefixes(path: str) -> List[str]:
"""Retrieves all possible path prefixes of a path, in descending order
of length. For instance:
* (Linux) `/a/b/c` returns `['/a/b/c', '/a/b', '/a', '/']`
* (Windows) `C:\\a\\b\\c` returns `['C:\\a\\b\\c', 'C:\\a\\b', 'C:\\a', 'C:']`
:param str path: the path to break into prefixes
:returns: all possible path prefixes of given path in descending order
:rtype: `list` of `str`
"""
prefix = os.path.normpath(path)
prefixes: List[str] = []
while prefix:
prefixes.append(prefix)
prefix, _ = os.path.split(prefix)
# break once we hit the root path
if prefix == prefixes[-1]:
break
return prefixes
[docs]def path_surgery(cmd: str) -> bool:
"""Attempt to perform PATH surgery to find cmd
Mitigates https://github.com/certbot/certbot/issues/1833
:param str cmd: the command that is being searched for in the PATH
:returns: True if the operation succeeded, False otherwise
"""
path = os.environ["PATH"]
added = []
for d in STANDARD_BINARY_DIRS:
if d not in path:
path += os.pathsep + d
added.append(d)
if any(added):
logger.debug("Can't find %s, attempting PATH mitigation by adding %s",
cmd, os.pathsep.join(added))
os.environ["PATH"] = path
if util.exe_exists(cmd):
return True
expanded = " expanded" if any(added) else ""
logger.debug("Failed to find executable %s in%s PATH: %s", cmd,
expanded, path)
return False