You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

372 lines
13 KiB
Python

import threading
from contextlib import contextmanager
import os
from os.path import abspath, join as pjoin
import shutil
from subprocess import check_call, check_output, STDOUT
import sys
from tempfile import mkdtemp
from . import compat
from .in_process import _in_proc_script_path
__all__ = [
'BackendUnavailable',
'BackendInvalid',
'HookMissing',
'UnsupportedOperation',
'default_subprocess_runner',
'quiet_subprocess_runner',
'Pep517HookCaller',
]
@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.
:param source_dir: The path to the source directory, containing
pyproject.toml.
:param build_backend: The build backend spec, as per PEP 517, from
pyproject.toml.
:param backend_path: The backend path, as per PEP 517, from pyproject.toml.
:param runner: A callable that invokes the wrapper subprocess.
:param python_executable: The Python executable used to invoke the backend
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,
python_executable=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
if not python_executable:
python_executable = sys.executable
self.python_executable = python_executable
@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_editable(self, config_settings=None):
"""Identify packages required for building an editable 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_editable', {
'config_settings': config_settings
})
def prepare_metadata_for_build_editable(
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 an editable
wheel, and the dist-info extracted from that (unless _allow_fallback is
False).
"""
return self._call_hook('prepare_metadata_for_build_editable', {
'metadata_directory': abspath(metadata_directory),
'config_settings': config_settings,
'_allow_fallback': _allow_fallback,
})
def build_editable(
self, wheel_directory, config_settings=None,
metadata_directory=None):
"""Build an editable wheel from this project.
Returns the name of the newly created file.
In general, this will call the 'build_editable' hook in the backend.
However, if that was previously called by
'prepare_metadata_for_build_editable', 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_editable', {
'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:
python = self.python_executable
self._subprocess_runner(
[python, abspath(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(data.get('missing_hook_name') or 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)