import os
import sys
import importlib
import argparse
import functools
import traceback
import contextlib
from io import StringIO
import subprocess
import re
import tempfile
import email.parser
print_err = functools.partial(print, file=sys.stderr)
# Some valid Python version specifiers are not supported.
# Whitelist characters we can handle.
VERSION_RE = re.compile('[a-zA-Z0-9.-]+')
class EndPass(Exception):
"""End current pass of generating requirements"""
try:
import toml
from packaging.requirements import Requirement, InvalidRequirement
from packaging.utils import canonicalize_name, canonicalize_version
try:
import importlib.metadata as importlib_metadata
except ImportError:
import importlib_metadata
except ImportError as e:
print_err('Import error:', e)
# already echoed by the %pyproject_buildrequires macro
sys.exit(0)
@contextlib.contextmanager
def hook_call():
captured_out = StringIO()
with contextlib.redirect_stdout(captured_out):
yield
for line in captured_out.getvalue().splitlines():
print_err('HOOK STDOUT:', line)
class Requirements:
"""Requirement printer"""
def __init__(self, get_installed_version, extras='',
python3_pkgversion='3'):
self.get_installed_version = get_installed_version
if extras:
self.marker_envs = [{'extra': e.strip()} for e in extras.split(',')]
else:
self.marker_envs = [{'extra': ''}]
self.missing_requirements = False
self.python3_pkgversion = python3_pkgversion
def evaluate_all_environamnets(self, requirement):
for marker_env in self.marker_envs:
if requirement.marker.evaluate(environment=marker_env):
return True
return False
def add(self, requirement_str, *, source=None):
"""Output a Python-style requirement string as RPM dep"""
print_err(f'Handling {requirement_str} from {source}')
try:
requirement = Requirement(requirement_str)
except InvalidRequirement as e:
print_err(
f'WARNING: Skipping invalid requirement: {requirement_str}\n'
+ f' {e}',
)
return
name = canonicalize_name(requirement.name)
if (requirement.marker is not None and
not self.evaluate_all_environamnets(requirement)):
print_err(f'Ignoring alien requirement:', requirement_str)
return
try:
installed = self.get_installed_version(requirement.name)
except importlib_metadata.PackageNotFoundError:
print_err(f'Requirement not satisfied: {requirement_str}')
installed = None
if installed and installed in requirement.specifier:
print_err(f'Requirement satisfied: {requirement_str}')
print_err(f' (installed: {requirement.name} {installed})')
else:
self.missing_requirements = True
together = []
for specifier in sorted(
requirement.specifier,
key=lambda s: (s.operator, s.version),
):
version = canonicalize_version(specifier.version)
if not VERSION_RE.fullmatch(str(specifier.version)):
raise ValueError(
f'Unknown character in version: {specifier.version}. '
+ '(This is probably a bug in pyproject-rpm-macros.)',
)
if specifier.operator == '!=':
lower = python3dist(name, '<', version,
self.python3_pkgversion)
higher = python3dist(name, '>', f'{version}.0',
self.python3_pkgversion)
together.append(
f'({lower} or {higher})'
)
else:
together.append(python3dist(name, specifier.operator, version,
self.python3_pkgversion))
if len(together) == 0:
print(python3dist(name,
python3_pkgversion=self.python3_pkgversion))
elif len(together) == 1:
print(together[0])
else:
print(f"({' and '.join(together)})")
def check(self, *, source=None):
"""End current pass if any unsatisfied dependencies were output"""
if self.missing_requirements:
print_err(f'Exiting dependency generation pass: {source}')
raise EndPass(source)
def extend(self, requirement_strs, *, source=None):
"""add() several requirements"""
for req_str in requirement_strs:
self.add(req_str, source=source)
def get_backend(requirements):
try:
f = open('pyproject.toml')
except FileNotFoundError:
pyproject_data = {}
else:
with f:
pyproject_data = toml.load(f)
buildsystem_data = pyproject_data.get('build-system', {})
requirements.extend(
buildsystem_data.get('requires', ()),
source='build-system.requires',
)
backend_name = buildsystem_data.get('build-backend')
if not backend_name:
# https://www.python.org/dev/peps/pep-0517/:
# If the pyproject.toml file is absent, or the build-backend key is
# missing, the source tree is not using this specification, and tools
# should revert to the legacy behaviour of running setup.py
# (either directly, or by implicitly invoking the [following] backend).
backend_name = 'setuptools.build_meta:__legacy__'
requirements.add('setuptools >= 40.8', source='default build backend')
requirements.add('wheel', source='default build backend')
requirements.check(source='build backend')
backend_path = buildsystem_data.get('backend-path')
if backend_path:
sys.path.insert(0, backend_path)
module_name, _, object_name = backend_name.partition(":")
backend_module = importlib.import_module(module_name)
if object_name:
return getattr(backend_module, object_name)
return backend_module
def generate_build_requirements(backend, requirements):
get_requires = getattr(backend, 'get_requires_for_build_wheel', None)
if get_requires:
with hook_call():
new_reqs = get_requires()
requirements.extend(new_reqs, source='get_requires_for_build_wheel')
def generate_run_requirements(backend, requirements):
hook_name = 'prepare_metadata_for_build_wheel'
prepare_metadata = getattr(backend, hook_name, None)
if not prepare_metadata:
raise ValueError(
'build backend cannot provide build metadata '
+ '(incl. runtime requirements) before buld'
)
with hook_call():
dir_basename = prepare_metadata('.')
with open(dir_basename + '/METADATA') as f:
message = email.parser.Parser().parse(f, headersonly=True)
for key in 'Requires', 'Requires-Dist':
requires = message.get_all(key, ())
requirements.extend(requires, source=f'wheel metadata: {key}')
def parse_tox_requires_lines(lines):
packages = []
for line in lines:
line = line.strip()
if line.startswith('-r'):
path = line[2:]
with open(path) as f:
packages.extend(parse_tox_requires_lines(f.read().splitlines()))
elif line.startswith('-'):
print_err(
f'WARNING: Skipping dependency line: {line}\n'
+ f' tox deps options other than -r are not supported (yet).',
)
else:
packages.append(line)
return packages
def generate_tox_requirements(toxenv, requirements):
requirements.add('tox-current-env >= 0.0.2', source='tox itself')
requirements.check(source='tox itself')
with tempfile.NamedTemporaryFile('r') as depfile:
r = subprocess.run(
[sys.executable, '-m', 'tox', '--print-deps-to-file',
depfile.name, '-qre', toxenv],
check=False,
encoding='utf-8',
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
)
if r.stdout:
print_err(r.stdout, end='')
r.check_returncode()
deplines = depfile.read().splitlines()
packages = parse_tox_requires_lines(deplines)
requirements.extend(packages,
source=f'tox --print-deps-only: {toxenv}')
def python3dist(name, op=None, version=None, python3_pkgversion="3"):
prefix = f"python{python3_pkgversion}dist"
if op is None:
if version is not None:
raise AssertionError('op and version go together')
return f'{prefix}({name})'
else:
return f'{prefix}({name}) {op} {version}'
def generate_requires(
*, include_runtime=False, toxenv=None, extras='',
get_installed_version=importlib_metadata.version, # for dep injection
python3_pkgversion="3",
):
"""Generate the BuildRequires for the project in the current directory
This is the main Python entry point.
"""
requirements = Requirements(
get_installed_version, extras=extras,
python3_pkgversion=python3_pkgversion
)
try:
backend = get_backend(requirements)
generate_build_requirements(backend, requirements)
if toxenv is not None:
include_runtime = True
generate_tox_requirements(toxenv, requirements)
if include_runtime:
generate_run_requirements(backend, requirements)
except EndPass:
return
def main(argv):
parser = argparse.ArgumentParser(
description='Generate BuildRequires for a Python project.'
)
parser.add_argument(
'-r', '--runtime', action='store_true',
help='Generate run-time requirements',
)
parser.add_argument(
'-e', '--toxenv', metavar='TOXENVS', default=None,
help=('specify tox environments'
'(implies --tox)'),
)
parser.add_argument(
'-t', '--tox', action='store_true',
help=('generate test tequirements from tox environment '
'(implies --runtime)'),
)
parser.add_argument(
'-x', '--extras', metavar='EXTRAS', default='',
help='comma separated list of "extras" for runtime requirements '
'(e.g. -x testing,feature-x) (implies --runtime)',
)
parser.add_argument(
'-p', '--python3_pkgversion', metavar='PYTHON3_PKGVERSION',
default="3", help=('Python version for pythonXdist()'
'or pythonX.Ydist() requirements'),
)
args = parser.parse_args(argv)
if args.toxenv:
args.tox = True
if args.tox:
args.runtime = True
args.toxenv = (args.toxenv or os.getenv('RPM_TOXENV') or
f'py{sys.version_info.major}{sys.version_info.minor}')
if args.extras:
args.runtime = True
try:
generate_requires(
include_runtime=args.runtime,
toxenv=args.toxenv,
extras=args.extras,
python3_pkgversion=args.python3_pkgversion,
)
except Exception:
# Log the traceback explicitly (it's useful debug info)
traceback.print_exc()
exit(1)
if __name__ == '__main__':
main(sys.argv[1:])