mitogen/ansible_mitogen/module_finder.py

282 lines
9.4 KiB
Python

# Copyright 2019, David Wilson
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its contributors
# may be used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
from __future__ import absolute_import, division, print_function
from __future__ import unicode_literals
__metaclass__ = type
import collections
import logging
import os
import re
import sys
try:
# Python >= 3.4, PEP 451 ModuleSpec API
import importlib.machinery
import importlib.util
except ImportError:
# Python < 3.4, PEP 302 Import Hooks
import imp
import mitogen.master
LOG = logging.getLogger(__name__)
PREFIX = 'ansible.module_utils.'
# Analog of `importlib.machinery.ModuleSpec` or `pkgutil.ModuleInfo`.
# name Unqualified name of the module.
# path Filesystem path of the module.
# kind One of the constants in `imp`, as returned in `imp.find_module()`
# parent `ansible_mitogen.module_finder.Module` of parent package (if any).
Module = collections.namedtuple('Module', 'name path kind parent')
def get_fullname(module):
"""
Reconstruct a Module's canonical path by recursing through its parents.
"""
bits = [str(module.name)]
while module.parent:
bits.append(str(module.parent.name))
module = module.parent
return '.'.join(reversed(bits))
def get_code(module):
"""
Compile and return a Module's code object.
"""
fp = open(module.path, 'rb')
try:
return compile(fp.read(), str(module.name), 'exec')
finally:
fp.close()
def is_pkg(module):
"""
Return :data:`True` if a Module represents a package.
"""
return module.kind == imp.PKG_DIRECTORY
def find(name, path=(), parent=None):
"""
Return a Module instance describing the first matching module found on the
search path.
:param str name:
Module name.
:param list path:
List of directory names to search for the module.
:param Module parent:
Optional module parent.
"""
assert isinstance(path, tuple)
head, _, tail = name.partition('.')
try:
tup = imp.find_module(head, list(path))
except ImportError:
return parent
fp, modpath, (suffix, mode, kind) = tup
if fp:
fp.close()
if parent and modpath == parent.path:
# 'from timeout import timeout', where 'timeout' is a function but also
# the name of the module being imported.
return None
if kind == imp.PKG_DIRECTORY:
modpath = os.path.join(modpath, '__init__.py')
module = Module(head, modpath, kind, parent)
# TODO: this code is entirely wrong on Python 3.x, but works well enough
# for Ansible. We need a new find_child() that only looks in the package
# directory, never falling back to the parent search path.
if tail and kind == imp.PKG_DIRECTORY:
return find_relative(module, tail, path)
return module
def find_relative(parent, name, path=()):
if parent.kind == imp.PKG_DIRECTORY:
path = (os.path.dirname(parent.path),) + path
return find(name, path, parent=parent)
def scan_fromlist(code):
"""Return an iterator of (level, name) for explicit imports in a code
object.
Not all names identify a module. `from os import name, path` generates
`(0, 'os.name'), (0, 'os.path')`, but `os.name` is usually a string.
>>> src = 'import a; import b.c; from d.e import f; from g import h, i\\n'
>>> code = compile(src, '<str>', 'exec')
>>> list(scan_fromlist(code))
[(0, 'a'), (0, 'b.c'), (0, 'd.e.f'), (0, 'g.h'), (0, 'g.i')]
"""
for level, modname_s, fromlist in mitogen.master.scan_code_imports(code):
for name in fromlist:
yield level, str('%s.%s' % (modname_s, name))
if not fromlist:
yield level, modname_s
def walk_imports(code, prefix=None):
"""Return an iterator of names for implicit parent imports & explicit
imports in a code object.
If a prefix is provided, then only children of that prefix are included.
Not all names identify a module. `from os import name, path` generates
`'os', 'os.name', 'os.path'`, but `os.name` is usually a string.
>>> source = 'import a; import b; import b.c; from b.d import e, f\\n'
>>> code = compile(source, '<str>', 'exec')
>>> list(walk_imports(code))
['a', 'b', 'b', 'b.c', 'b', 'b.d', 'b.d.e', 'b.d.f']
>>> list(walk_imports(code, prefix='b'))
['b.c', 'b.d', 'b.d.e', 'b.d.f']
"""
if prefix is None:
prefix = ''
pattern = re.compile(r'(^|\.)(\w+)')
start = len(prefix)
for _, name, fromlist in mitogen.master.scan_code_imports(code):
if not name.startswith(prefix):
continue
for match in pattern.finditer(name, start):
yield name[:match.end()]
for leaf in fromlist:
yield str('%s.%s' % (name, leaf))
def scan(module_name, module_path, search_path):
# type: (str, str, list[str]) -> list[(str, str, bool)]
"""Return a list of (name, path, is_package) for ansible.module_utils
imports used by an Ansible module.
"""
log = LOG.getChild('scan')
log.debug('%r, %r, %r', module_name, module_path, search_path)
if sys.version_info >= (3, 4):
result = _scan_importlib_find_spec(
module_name, module_path, search_path,
)
log.debug('_scan_importlib_find_spec %r', result)
else:
result = _scan_imp_find_module(module_name, module_path, search_path)
log.debug('_scan_imp_find_module %r', result)
return result
def _scan_importlib_find_spec(module_name, module_path, search_path):
# type: (str, str, list[str]) -> list[(str, str, bool)]
module = importlib.machinery.ModuleSpec(
module_name, loader=None, origin=module_path,
)
prefix = importlib.machinery.ModuleSpec(
PREFIX.rstrip('.'), loader=None,
)
prefix.submodule_search_locations = search_path
queue = collections.deque([module])
specs = {prefix.name: prefix}
while queue:
spec = queue.popleft()
if spec.origin is None:
continue
try:
with open(spec.origin, 'rb') as f:
code = compile(f.read(), spec.name, 'exec')
except Exception as exc:
raise ValueError((exc, module, spec, specs))
for name in walk_imports(code, prefix.name):
if name in specs:
continue
parent_name = name.rpartition('.')[0]
parent = specs[parent_name]
if parent is None or not parent.submodule_search_locations:
specs[name] = None
continue
child = importlib.util._find_spec(
name, parent.submodule_search_locations,
)
if child is None or child.origin is None:
specs[name] = None
continue
specs[name] = child
queue.append(child)
del specs[prefix.name]
return sorted(
(spec.name, spec.origin, spec.submodule_search_locations is not None)
for spec in specs.values() if spec is not None
)
def _scan_imp_find_module(module_name, module_path, search_path):
# type: (str, str, list[str]) -> list[(str, str, bool)]
module = Module(module_name, module_path, imp.PY_SOURCE, None)
stack = [module]
seen = set()
while stack:
module = stack.pop(0)
for level, fromname in scan_fromlist(get_code(module)):
if not fromname.startswith(PREFIX):
continue
imported = find(fromname[len(PREFIX):], search_path)
if imported is None or imported in seen:
continue
seen.add(imported)
stack.append(imported)
parent = imported.parent
while parent:
fullname = get_fullname(parent)
module = Module(fullname, parent.path, parent.kind, None)
if module not in seen:
seen.add(module)
stack.append(module)
parent = parent.parent
return sorted(
(PREFIX + get_fullname(module), module.path, is_pkg(module))
for module in seen
)