| import threading |
| from contextlib import contextmanager |
| import os |
| from os.path import dirname, abspath, join as pjoin |
| import shutil |
| from subprocess import check_call, check_output, STDOUT |
| import sys |
| from tempfile import mkdtemp |
| |
| from . import compat |
| |
| |
| try: |
| import importlib.resources as resources |
| |
| def _in_proc_script_path(): |
| return resources.path(__package__, '_in_process.py') |
| except ImportError: |
| @contextmanager |
| def _in_proc_script_path(): |
| yield pjoin(dirname(abspath(__file__)), '_in_process.py') |
| |
| |
| @contextmanager |
| def tempdir(): |
| td = mkdtemp() |
| try: |
| yield td |
| finally: |
| shutil.rmtree(td) |
| |
| |
| class BackendUnavailable(Exception): |
| """Will be raised if the backend cannot be imported in the hook process.""" |
| def __init__(self, traceback): |
| self.traceback = traceback |
| |
| |
| class BackendInvalid(Exception): |
| """Will be raised if the backend is invalid.""" |
| def __init__(self, backend_name, backend_path, message): |
| self.backend_name = backend_name |
| self.backend_path = backend_path |
| self.message = message |
| |
| |
| class HookMissing(Exception): |
| """Will be raised on missing hooks.""" |
| def __init__(self, hook_name): |
| super(HookMissing, self).__init__(hook_name) |
| self.hook_name = hook_name |
| |
| |
| class UnsupportedOperation(Exception): |
| """May be raised by build_sdist if the backend indicates that it can't.""" |
| def __init__(self, traceback): |
| self.traceback = traceback |
| |
| |
| def default_subprocess_runner(cmd, cwd=None, extra_environ=None): |
| """The default method of calling the wrapper subprocess.""" |
| env = os.environ.copy() |
| if extra_environ: |
| env.update(extra_environ) |
| |
| check_call(cmd, cwd=cwd, env=env) |
| |
| |
| def quiet_subprocess_runner(cmd, cwd=None, extra_environ=None): |
| """A method of calling the wrapper subprocess while suppressing output.""" |
| env = os.environ.copy() |
| if extra_environ: |
| env.update(extra_environ) |
| |
| check_output(cmd, cwd=cwd, env=env, stderr=STDOUT) |
| |
| |
| def norm_and_check(source_tree, requested): |
| """Normalise and check a backend path. |
| |
| Ensure that the requested backend path is specified as a relative path, |
| and resolves to a location under the given source tree. |
| |
| Return an absolute version of the requested path. |
| """ |
| if os.path.isabs(requested): |
| raise ValueError("paths must be relative") |
| |
| abs_source = os.path.abspath(source_tree) |
| abs_requested = os.path.normpath(os.path.join(abs_source, requested)) |
| # We have to use commonprefix for Python 2.7 compatibility. So we |
| # normalise case to avoid problems because commonprefix is a character |
| # based comparison :-( |
| norm_source = os.path.normcase(abs_source) |
| norm_requested = os.path.normcase(abs_requested) |
| if os.path.commonprefix([norm_source, norm_requested]) != norm_source: |
| raise ValueError("paths must be inside source tree") |
| |
| return abs_requested |
| |
| |
| class Pep517HookCaller(object): |
| """A wrapper around a source directory to be built with a PEP 517 backend. |
| |
| source_dir : The path to the source directory, containing pyproject.toml. |
| build_backend : The build backend spec, as per PEP 517, from |
| pyproject.toml. |
| backend_path : The backend path, as per PEP 517, from pyproject.toml. |
| runner : A callable that invokes the wrapper subprocess. |
| |
| The 'runner', if provided, must expect the following: |
| cmd : a list of strings representing the command and arguments to |
| execute, as would be passed to e.g. 'subprocess.check_call'. |
| cwd : a string representing the working directory that must be |
| used for the subprocess. Corresponds to the provided source_dir. |
| extra_environ : a dict mapping environment variable names to values |
| which must be set for the subprocess execution. |
| """ |
| def __init__( |
| self, |
| source_dir, |
| build_backend, |
| backend_path=None, |
| runner=None, |
| ): |
| if runner is None: |
| runner = default_subprocess_runner |
| |
| self.source_dir = abspath(source_dir) |
| self.build_backend = build_backend |
| if backend_path: |
| backend_path = [ |
| norm_and_check(self.source_dir, p) for p in backend_path |
| ] |
| self.backend_path = backend_path |
| self._subprocess_runner = runner |
| |
| @contextmanager |
| def subprocess_runner(self, runner): |
| """A context manager for temporarily overriding the default subprocess |
| runner. |
| """ |
| prev = self._subprocess_runner |
| self._subprocess_runner = runner |
| try: |
| yield |
| finally: |
| self._subprocess_runner = prev |
| |
| def get_requires_for_build_wheel(self, config_settings=None): |
| """Identify packages required for building a wheel |
| |
| Returns a list of dependency specifications, e.g.: |
| ["wheel >= 0.25", "setuptools"] |
| |
| This does not include requirements specified in pyproject.toml. |
| It returns the result of calling the equivalently named hook in a |
| subprocess. |
| """ |
| return self._call_hook('get_requires_for_build_wheel', { |
| 'config_settings': config_settings |
| }) |
| |
| def prepare_metadata_for_build_wheel( |
| self, metadata_directory, config_settings=None, |
| _allow_fallback=True): |
| """Prepare a *.dist-info folder with metadata for this project. |
| |
| Returns the name of the newly created folder. |
| |
| If the build backend defines a hook with this name, it will be called |
| in a subprocess. If not, the backend will be asked to build a wheel, |
| and the dist-info extracted from that (unless _allow_fallback is |
| False). |
| """ |
| return self._call_hook('prepare_metadata_for_build_wheel', { |
| 'metadata_directory': abspath(metadata_directory), |
| 'config_settings': config_settings, |
| '_allow_fallback': _allow_fallback, |
| }) |
| |
| def build_wheel( |
| self, wheel_directory, config_settings=None, |
| metadata_directory=None): |
| """Build a wheel from this project. |
| |
| Returns the name of the newly created file. |
| |
| In general, this will call the 'build_wheel' hook in the backend. |
| However, if that was previously called by |
| 'prepare_metadata_for_build_wheel', and the same metadata_directory is |
| used, the previously built wheel will be copied to wheel_directory. |
| """ |
| if metadata_directory is not None: |
| metadata_directory = abspath(metadata_directory) |
| return self._call_hook('build_wheel', { |
| 'wheel_directory': abspath(wheel_directory), |
| 'config_settings': config_settings, |
| 'metadata_directory': metadata_directory, |
| }) |
| |
| def get_requires_for_build_sdist(self, config_settings=None): |
| """Identify packages required for building a wheel |
| |
| Returns a list of dependency specifications, e.g.: |
| ["setuptools >= 26"] |
| |
| This does not include requirements specified in pyproject.toml. |
| It returns the result of calling the equivalently named hook in a |
| subprocess. |
| """ |
| return self._call_hook('get_requires_for_build_sdist', { |
| 'config_settings': config_settings |
| }) |
| |
| def build_sdist(self, sdist_directory, config_settings=None): |
| """Build an sdist from this project. |
| |
| Returns the name of the newly created file. |
| |
| This calls the 'build_sdist' backend hook in a subprocess. |
| """ |
| return self._call_hook('build_sdist', { |
| 'sdist_directory': abspath(sdist_directory), |
| 'config_settings': config_settings, |
| }) |
| |
| def _call_hook(self, hook_name, kwargs): |
| # On Python 2, pytoml returns Unicode values (which is correct) but the |
| # environment passed to check_call needs to contain string values. We |
| # convert here by encoding using ASCII (the backend can only contain |
| # letters, digits and _, . and : characters, and will be used as a |
| # Python identifier, so non-ASCII content is wrong on Python 2 in |
| # any case). |
| # For backend_path, we use sys.getfilesystemencoding. |
| if sys.version_info[0] == 2: |
| build_backend = self.build_backend.encode('ASCII') |
| else: |
| build_backend = self.build_backend |
| extra_environ = {'PEP517_BUILD_BACKEND': build_backend} |
| |
| if self.backend_path: |
| backend_path = os.pathsep.join(self.backend_path) |
| if sys.version_info[0] == 2: |
| backend_path = backend_path.encode(sys.getfilesystemencoding()) |
| extra_environ['PEP517_BACKEND_PATH'] = backend_path |
| |
| with tempdir() as td: |
| hook_input = {'kwargs': kwargs} |
| compat.write_json(hook_input, pjoin(td, 'input.json'), |
| indent=2) |
| |
| # Run the hook in a subprocess |
| with _in_proc_script_path() as script: |
| self._subprocess_runner( |
| [sys.executable, str(script), hook_name, td], |
| cwd=self.source_dir, |
| extra_environ=extra_environ |
| ) |
| |
| data = compat.read_json(pjoin(td, 'output.json')) |
| if data.get('unsupported'): |
| raise UnsupportedOperation(data.get('traceback', '')) |
| if data.get('no_backend'): |
| raise BackendUnavailable(data.get('traceback', '')) |
| if data.get('backend_invalid'): |
| raise BackendInvalid( |
| backend_name=self.build_backend, |
| backend_path=self.backend_path, |
| message=data.get('backend_error', '') |
| ) |
| if data.get('hook_missing'): |
| raise HookMissing(hook_name) |
| return data['return_val'] |
| |
| |
| class LoggerWrapper(threading.Thread): |
| """ |
| Read messages from a pipe and redirect them |
| to a logger (see python's logging module). |
| """ |
| |
| def __init__(self, logger, level): |
| threading.Thread.__init__(self) |
| self.daemon = True |
| |
| self.logger = logger |
| self.level = level |
| |
| # create the pipe and reader |
| self.fd_read, self.fd_write = os.pipe() |
| self.reader = os.fdopen(self.fd_read) |
| |
| self.start() |
| |
| def fileno(self): |
| return self.fd_write |
| |
| @staticmethod |
| def remove_newline(msg): |
| return msg[:-1] if msg.endswith(os.linesep) else msg |
| |
| def run(self): |
| for line in self.reader: |
| self._write(self.remove_newline(line)) |
| |
| def _write(self, message): |
| self.logger.log(self.level, message) |
