synapse-old/synapse/util/check_dependencies.py

128 lines
4.4 KiB
Python

import logging
from typing import Iterable, NamedTuple, Optional
from packaging.requirements import Requirement
DISTRIBUTION_NAME = "matrix-synapse"
try:
from importlib import metadata
except ImportError:
import importlib_metadata as metadata # type: ignore[no-redef]
class DependencyException(Exception):
@property
def message(self) -> str:
return "\n".join(
[
"Missing Requirements: %s" % (", ".join(self.dependencies),),
"To install run:",
" pip install --upgrade --force %s" % (" ".join(self.dependencies),),
"",
]
)
@property
def dependencies(self) -> Iterable[str]:
for i in self.args[0]:
yield '"' + i + '"'
EXTRAS = set(metadata.metadata(DISTRIBUTION_NAME).get_all("Provides-Extra"))
class Dependency(NamedTuple):
requirement: Requirement
must_be_installed: bool
def _generic_dependencies() -> Iterable[Dependency]:
"""Yield pairs (requirement, must_be_installed)."""
requirements = metadata.requires(DISTRIBUTION_NAME)
assert requirements is not None
for raw_requirement in requirements:
req = Requirement(raw_requirement)
# https://packaging.pypa.io/en/latest/markers.html#usage notes that
# > Evaluating an extra marker with no environment is an error
# so we pass in a dummy empty extra value here.
must_be_installed = req.marker is None or req.marker.evaluate({"extra": ""})
yield Dependency(req, must_be_installed)
def _dependencies_for_extra(extra: str) -> Iterable[Dependency]:
"""Yield additional dependencies needed for a given `extra`."""
requirements = metadata.requires(DISTRIBUTION_NAME)
assert requirements is not None
for raw_requirement in requirements:
req = Requirement(raw_requirement)
# Exclude mandatory deps by only selecting deps needed with this extra.
if (
req.marker is not None
and req.marker.evaluate({"extra": extra})
and not req.marker.evaluate({"extra": ""})
):
yield Dependency(req, True)
def _not_installed(requirement: Requirement, extra: Optional[str] = None) -> str:
if extra:
return f"Need {requirement.name} for {extra}, but it is not installed"
else:
return f"Need {requirement.name}, but it is not installed"
def _incorrect_version(
requirement: Requirement, got: str, extra: Optional[str] = None
) -> str:
if extra:
return f"Need {requirement} for {extra}, but got {requirement.name}=={got}"
else:
return f"Need {requirement}, but got {requirement.name}=={got}"
def check_requirements(extra: Optional[str] = None) -> None:
"""Check Synapse's dependencies are present and correctly versioned.
If provided, `extra` must be the name of an pacakging extra (e.g. "saml2" in
`pip install matrix-synapse[saml2]`).
If `extra` is None, this function checks that
- all mandatory dependencies are installed and correctly versioned, and
- each optional dependency that's installed is correctly versioned.
If `extra` is not None, this function checks that
- the dependencies needed for that extra are installed and correctly versioned.
:raises DependencyException: if a dependency is missing or incorrectly versioned.
:raises ValueError: if this extra does not exist.
"""
# First work out which dependencies are required, and which are optional.
if extra is None:
dependencies = _generic_dependencies()
elif extra in EXTRAS:
dependencies = _dependencies_for_extra(extra)
else:
raise ValueError(f"Synapse does not provide the feature '{extra}'")
deps_unfulfilled = []
errors = []
for (requirement, must_be_installed) in dependencies:
try:
dist: metadata.Distribution = metadata.distribution(requirement.name)
except metadata.PackageNotFoundError:
if must_be_installed:
deps_unfulfilled.append(requirement.name)
errors.append(_not_installed(requirement, extra))
else:
if not requirement.specifier.contains(dist.version):
deps_unfulfilled.append(requirement.name)
errors.append(_incorrect_version(requirement, dist.version, extra))
if deps_unfulfilled:
for err in errors:
logging.error(err)
raise DependencyException(deps_unfulfilled)