1"""Build wheels/sdists by installing build deps to a temporary environment. 2""" 3 4import os 5import logging 6from pip._vendor import toml 7import shutil 8from subprocess import check_call 9import sys 10from sysconfig import get_paths 11from tempfile import mkdtemp 12 13from .wrappers import Pep517HookCaller, LoggerWrapper 14 15log = logging.getLogger(__name__) 16 17 18def _load_pyproject(source_dir): 19 with open(os.path.join(source_dir, 'pyproject.toml')) as f: 20 pyproject_data = toml.load(f) 21 buildsys = pyproject_data['build-system'] 22 return ( 23 buildsys['requires'], 24 buildsys['build-backend'], 25 buildsys.get('backend-path'), 26 ) 27 28 29class BuildEnvironment(object): 30 """Context manager to install build deps in a simple temporary environment 31 32 Based on code I wrote for pip, which is MIT licensed. 33 """ 34 # Copyright (c) 2008-2016 The pip developers (see AUTHORS.txt file) 35 # 36 # Permission is hereby granted, free of charge, to any person obtaining 37 # a copy of this software and associated documentation files (the 38 # "Software"), to deal in the Software without restriction, including 39 # without limitation the rights to use, copy, modify, merge, publish, 40 # distribute, sublicense, and/or sell copies of the Software, and to 41 # permit persons to whom the Software is furnished to do so, subject to 42 # the following conditions: 43 # 44 # The above copyright notice and this permission notice shall be 45 # included in all copies or substantial portions of the Software. 46 # 47 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 48 # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 49 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 50 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 51 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 52 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 53 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 54 55 path = None 56 57 def __init__(self, cleanup=True): 58 self._cleanup = cleanup 59 60 def __enter__(self): 61 self.path = mkdtemp(prefix='pep517-build-env-') 62 log.info('Temporary build environment: %s', self.path) 63 64 self.save_path = os.environ.get('PATH', None) 65 self.save_pythonpath = os.environ.get('PYTHONPATH', None) 66 67 install_scheme = 'nt' if (os.name == 'nt') else 'posix_prefix' 68 install_dirs = get_paths(install_scheme, vars={ 69 'base': self.path, 70 'platbase': self.path, 71 }) 72 73 scripts = install_dirs['scripts'] 74 if self.save_path: 75 os.environ['PATH'] = scripts + os.pathsep + self.save_path 76 else: 77 os.environ['PATH'] = scripts + os.pathsep + os.defpath 78 79 if install_dirs['purelib'] == install_dirs['platlib']: 80 lib_dirs = install_dirs['purelib'] 81 else: 82 lib_dirs = install_dirs['purelib'] + os.pathsep + \ 83 install_dirs['platlib'] 84 if self.save_pythonpath: 85 os.environ['PYTHONPATH'] = lib_dirs + os.pathsep + \ 86 self.save_pythonpath 87 else: 88 os.environ['PYTHONPATH'] = lib_dirs 89 90 return self 91 92 def pip_install(self, reqs): 93 """Install dependencies into this env by calling pip in a subprocess""" 94 if not reqs: 95 return 96 log.info('Calling pip to install %s', reqs) 97 cmd = [ 98 sys.executable, '-m', 'pip', 'install', '--ignore-installed', 99 '--prefix', self.path] + list(reqs) 100 check_call( 101 cmd, 102 stdout=LoggerWrapper(log, logging.INFO), 103 stderr=LoggerWrapper(log, logging.ERROR), 104 ) 105 106 def __exit__(self, exc_type, exc_val, exc_tb): 107 needs_cleanup = ( 108 self._cleanup and 109 self.path is not None and 110 os.path.isdir(self.path) 111 ) 112 if needs_cleanup: 113 shutil.rmtree(self.path) 114 115 if self.save_path is None: 116 os.environ.pop('PATH', None) 117 else: 118 os.environ['PATH'] = self.save_path 119 120 if self.save_pythonpath is None: 121 os.environ.pop('PYTHONPATH', None) 122 else: 123 os.environ['PYTHONPATH'] = self.save_pythonpath 124 125 126def build_wheel(source_dir, wheel_dir, config_settings=None): 127 """Build a wheel from a source directory using PEP 517 hooks. 128 129 :param str source_dir: Source directory containing pyproject.toml 130 :param str wheel_dir: Target directory to create wheel in 131 :param dict config_settings: Options to pass to build backend 132 133 This is a blocking function which will run pip in a subprocess to install 134 build requirements. 135 """ 136 if config_settings is None: 137 config_settings = {} 138 requires, backend, backend_path = _load_pyproject(source_dir) 139 hooks = Pep517HookCaller(source_dir, backend, backend_path) 140 141 with BuildEnvironment() as env: 142 env.pip_install(requires) 143 reqs = hooks.get_requires_for_build_wheel(config_settings) 144 env.pip_install(reqs) 145 return hooks.build_wheel(wheel_dir, config_settings) 146 147 148def build_sdist(source_dir, sdist_dir, config_settings=None): 149 """Build an sdist from a source directory using PEP 517 hooks. 150 151 :param str source_dir: Source directory containing pyproject.toml 152 :param str sdist_dir: Target directory to place sdist in 153 :param dict config_settings: Options to pass to build backend 154 155 This is a blocking function which will run pip in a subprocess to install 156 build requirements. 157 """ 158 if config_settings is None: 159 config_settings = {} 160 requires, backend, backend_path = _load_pyproject(source_dir) 161 hooks = Pep517HookCaller(source_dir, backend, backend_path) 162 163 with BuildEnvironment() as env: 164 env.pip_install(requires) 165 reqs = hooks.get_requires_for_build_sdist(config_settings) 166 env.pip_install(reqs) 167 return hooks.build_sdist(sdist_dir, config_settings) 168