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:])