Alle Dateien aus dem Pythonkurs
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

150 lines
5.0 KiB

"""Validation of dependencies of packages
"""
import logging
from typing import Callable, Dict, List, NamedTuple, Optional, Set, Tuple
from pip._vendor.packaging.requirements import Requirement
from pip._vendor.packaging.utils import NormalizedName, canonicalize_name
from pip._internal.distributions import make_distribution_for_install_requirement
from pip._internal.metadata import get_default_environment
from pip._internal.metadata.base import DistributionVersion
from pip._internal.req.req_install import InstallRequirement
logger = logging.getLogger(__name__)
class PackageDetails(NamedTuple):
version: DistributionVersion
dependencies: List[Requirement]
# Shorthands
PackageSet = Dict[NormalizedName, PackageDetails]
Missing = Tuple[NormalizedName, Requirement]
Conflicting = Tuple[NormalizedName, DistributionVersion, Requirement]
MissingDict = Dict[NormalizedName, List[Missing]]
ConflictingDict = Dict[NormalizedName, List[Conflicting]]
CheckResult = Tuple[MissingDict, ConflictingDict]
ConflictDetails = Tuple[PackageSet, CheckResult]
def create_package_set_from_installed() -> Tuple[PackageSet, bool]:
"""Converts a list of distributions into a PackageSet."""
package_set = {}
problems = False
env = get_default_environment()
for dist in env.iter_installed_distributions(local_only=False, skip=()):
name = dist.canonical_name
try:
dependencies = list(dist.iter_dependencies())
package_set[name] = PackageDetails(dist.version, dependencies)
except (OSError, ValueError) as e:
# Don't crash on unreadable or broken metadata.
logger.warning("Error parsing requirements for %s: %s", name, e)
problems = True
return package_set, problems
def check_package_set(
package_set: PackageSet, should_ignore: Optional[Callable[[str], bool]] = None
) -> CheckResult:
"""Check if a package set is consistent
If should_ignore is passed, it should be a callable that takes a
package name and returns a boolean.
"""
missing = {}
conflicting = {}
for package_name, package_detail in package_set.items():
# Info about dependencies of package_name
missing_deps: Set[Missing] = set()
conflicting_deps: Set[Conflicting] = set()
if should_ignore and should_ignore(package_name):
continue
for req in package_detail.dependencies:
name = canonicalize_name(req.name)
# Check if it's missing
if name not in package_set:
missed = True
if req.marker is not None:
missed = req.marker.evaluate({"extra": ""})
if missed:
missing_deps.add((name, req))
continue
# Check if there's a conflict
version = package_set[name].version
if not req.specifier.contains(version, prereleases=True):
conflicting_deps.add((name, version, req))
if missing_deps:
missing[package_name] = sorted(missing_deps, key=str)
if conflicting_deps:
conflicting[package_name] = sorted(conflicting_deps, key=str)
return missing, conflicting
def check_install_conflicts(to_install: List[InstallRequirement]) -> ConflictDetails:
"""For checking if the dependency graph would be consistent after \
installing given requirements
"""
# Start from the current state
package_set, _ = create_package_set_from_installed()
# Install packages
would_be_installed = _simulate_installation_of(to_install, package_set)
# Only warn about directly-dependent packages; create a whitelist of them
whitelist = _create_whitelist(would_be_installed, package_set)
return (
package_set,
check_package_set(
package_set, should_ignore=lambda name: name not in whitelist
),
)
def _simulate_installation_of(
to_install: List[InstallRequirement], package_set: PackageSet
) -> Set[NormalizedName]:
"""Computes the version of packages after installing to_install."""
# Keep track of packages that were installed
installed = set()
# Modify it as installing requirement_set would (assuming no errors)
for inst_req in to_install:
abstract_dist = make_distribution_for_install_requirement(inst_req)
dist = abstract_dist.get_metadata_distribution()
name = dist.canonical_name
package_set[name] = PackageDetails(dist.version, list(dist.iter_dependencies()))
installed.add(name)
return installed
def _create_whitelist(
would_be_installed: Set[NormalizedName], package_set: PackageSet
) -> Set[NormalizedName]:
packages_affected = set(would_be_installed)
for package_name in package_set:
if package_name in packages_affected:
continue
for req in package_set[package_name].dependencies:
if canonicalize_name(req.name) in packages_affected:
packages_affected.add(package_name)
break
return packages_affected