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"""distutils.cmd | |
Provides the Command class, the base class for the command classes | |
in the distutils.command package. | |
""" | |
import sys | |
import os | |
import re | |
import logging | |
from .errors import DistutilsOptionError | |
from . import util, dir_util, file_util, archive_util, dep_util | |
from ._log import log | |
class Command: | |
"""Abstract base class for defining command classes, the "worker bees" | |
of the Distutils. A useful analogy for command classes is to think of | |
them as subroutines with local variables called "options". The options | |
are "declared" in 'initialize_options()' and "defined" (given their | |
final values, aka "finalized") in 'finalize_options()', both of which | |
must be defined by every command class. The distinction between the | |
two is necessary because option values might come from the outside | |
world (command line, config file, ...), and any options dependent on | |
other options must be computed *after* these outside influences have | |
been processed -- hence 'finalize_options()'. The "body" of the | |
subroutine, where it does all its work based on the values of its | |
options, is the 'run()' method, which must also be implemented by every | |
command class. | |
""" | |
# 'sub_commands' formalizes the notion of a "family" of commands, | |
# eg. "install" as the parent with sub-commands "install_lib", | |
# "install_headers", etc. The parent of a family of commands | |
# defines 'sub_commands' as a class attribute; it's a list of | |
# (command_name : string, predicate : unbound_method | string | None) | |
# tuples, where 'predicate' is a method of the parent command that | |
# determines whether the corresponding command is applicable in the | |
# current situation. (Eg. we "install_headers" is only applicable if | |
# we have any C header files to install.) If 'predicate' is None, | |
# that command is always applicable. | |
# | |
# 'sub_commands' is usually defined at the *end* of a class, because | |
# predicates can be unbound methods, so they must already have been | |
# defined. The canonical example is the "install" command. | |
sub_commands = [] | |
# -- Creation/initialization methods ------------------------------- | |
def __init__(self, dist): | |
"""Create and initialize a new Command object. Most importantly, | |
invokes the 'initialize_options()' method, which is the real | |
initializer and depends on the actual command being | |
instantiated. | |
""" | |
# late import because of mutual dependence between these classes | |
from distutils.dist import Distribution | |
if not isinstance(dist, Distribution): | |
raise TypeError("dist must be a Distribution instance") | |
if self.__class__ is Command: | |
raise RuntimeError("Command is an abstract class") | |
self.distribution = dist | |
self.initialize_options() | |
# Per-command versions of the global flags, so that the user can | |
# customize Distutils' behaviour command-by-command and let some | |
# commands fall back on the Distribution's behaviour. None means | |
# "not defined, check self.distribution's copy", while 0 or 1 mean | |
# false and true (duh). Note that this means figuring out the real | |
# value of each flag is a touch complicated -- hence "self._dry_run" | |
# will be handled by __getattr__, below. | |
# XXX This needs to be fixed. | |
self._dry_run = None | |
# verbose is largely ignored, but needs to be set for | |
# backwards compatibility (I think)? | |
self.verbose = dist.verbose | |
# Some commands define a 'self.force' option to ignore file | |
# timestamps, but methods defined *here* assume that | |
# 'self.force' exists for all commands. So define it here | |
# just to be safe. | |
self.force = None | |
# The 'help' flag is just used for command-line parsing, so | |
# none of that complicated bureaucracy is needed. | |
self.help = 0 | |
# 'finalized' records whether or not 'finalize_options()' has been | |
# called. 'finalize_options()' itself should not pay attention to | |
# this flag: it is the business of 'ensure_finalized()', which | |
# always calls 'finalize_options()', to respect/update it. | |
self.finalized = 0 | |
# XXX A more explicit way to customize dry_run would be better. | |
def __getattr__(self, attr): | |
if attr == 'dry_run': | |
myval = getattr(self, "_" + attr) | |
if myval is None: | |
return getattr(self.distribution, attr) | |
else: | |
return myval | |
else: | |
raise AttributeError(attr) | |
def ensure_finalized(self): | |
if not self.finalized: | |
self.finalize_options() | |
self.finalized = 1 | |
# Subclasses must define: | |
# initialize_options() | |
# provide default values for all options; may be customized by | |
# setup script, by options from config file(s), or by command-line | |
# options | |
# finalize_options() | |
# decide on the final values for all options; this is called | |
# after all possible intervention from the outside world | |
# (command-line, option file, etc.) has been processed | |
# run() | |
# run the command: do whatever it is we're here to do, | |
# controlled by the command's various option values | |
def initialize_options(self): | |
"""Set default values for all the options that this command | |
supports. Note that these defaults may be overridden by other | |
commands, by the setup script, by config files, or by the | |
command-line. Thus, this is not the place to code dependencies | |
between options; generally, 'initialize_options()' implementations | |
are just a bunch of "self.foo = None" assignments. | |
This method must be implemented by all command classes. | |
""" | |
raise RuntimeError( | |
"abstract method -- subclass %s must override" % self.__class__ | |
) | |
def finalize_options(self): | |
"""Set final values for all the options that this command supports. | |
This is always called as late as possible, ie. after any option | |
assignments from the command-line or from other commands have been | |
done. Thus, this is the place to code option dependencies: if | |
'foo' depends on 'bar', then it is safe to set 'foo' from 'bar' as | |
long as 'foo' still has the same value it was assigned in | |
'initialize_options()'. | |
This method must be implemented by all command classes. | |
""" | |
raise RuntimeError( | |
"abstract method -- subclass %s must override" % self.__class__ | |
) | |
def dump_options(self, header=None, indent=""): | |
from distutils.fancy_getopt import longopt_xlate | |
if header is None: | |
header = "command options for '%s':" % self.get_command_name() | |
self.announce(indent + header, level=logging.INFO) | |
indent = indent + " " | |
for (option, _, _) in self.user_options: | |
option = option.translate(longopt_xlate) | |
if option[-1] == "=": | |
option = option[:-1] | |
value = getattr(self, option) | |
self.announce(indent + "{} = {}".format(option, value), level=logging.INFO) | |
def run(self): | |
"""A command's raison d'etre: carry out the action it exists to | |
perform, controlled by the options initialized in | |
'initialize_options()', customized by other commands, the setup | |
script, the command-line, and config files, and finalized in | |
'finalize_options()'. All terminal output and filesystem | |
interaction should be done by 'run()'. | |
This method must be implemented by all command classes. | |
""" | |
raise RuntimeError( | |
"abstract method -- subclass %s must override" % self.__class__ | |
) | |
def announce(self, msg, level=logging.DEBUG): | |
log.log(level, msg) | |
def debug_print(self, msg): | |
"""Print 'msg' to stdout if the global DEBUG (taken from the | |
DISTUTILS_DEBUG environment variable) flag is true. | |
""" | |
from distutils.debug import DEBUG | |
if DEBUG: | |
print(msg) | |
sys.stdout.flush() | |
# -- Option validation methods ------------------------------------- | |
# (these are very handy in writing the 'finalize_options()' method) | |
# | |
# NB. the general philosophy here is to ensure that a particular option | |
# value meets certain type and value constraints. If not, we try to | |
# force it into conformance (eg. if we expect a list but have a string, | |
# split the string on comma and/or whitespace). If we can't force the | |
# option into conformance, raise DistutilsOptionError. Thus, command | |
# classes need do nothing more than (eg.) | |
# self.ensure_string_list('foo') | |
# and they can be guaranteed that thereafter, self.foo will be | |
# a list of strings. | |
def _ensure_stringlike(self, option, what, default=None): | |
val = getattr(self, option) | |
if val is None: | |
setattr(self, option, default) | |
return default | |
elif not isinstance(val, str): | |
raise DistutilsOptionError( | |
"'{}' must be a {} (got `{}`)".format(option, what, val) | |
) | |
return val | |
def ensure_string(self, option, default=None): | |
"""Ensure that 'option' is a string; if not defined, set it to | |
'default'. | |
""" | |
self._ensure_stringlike(option, "string", default) | |
def ensure_string_list(self, option): | |
r"""Ensure that 'option' is a list of strings. If 'option' is | |
currently a string, we split it either on /,\s*/ or /\s+/, so | |
"foo bar baz", "foo,bar,baz", and "foo, bar baz" all become | |
["foo", "bar", "baz"]. | |
""" | |
val = getattr(self, option) | |
if val is None: | |
return | |
elif isinstance(val, str): | |
setattr(self, option, re.split(r',\s*|\s+', val)) | |
else: | |
if isinstance(val, list): | |
ok = all(isinstance(v, str) for v in val) | |
else: | |
ok = False | |
if not ok: | |
raise DistutilsOptionError( | |
"'{}' must be a list of strings (got {!r})".format(option, val) | |
) | |
def _ensure_tested_string(self, option, tester, what, error_fmt, default=None): | |
val = self._ensure_stringlike(option, what, default) | |
if val is not None and not tester(val): | |
raise DistutilsOptionError( | |
("error in '%s' option: " + error_fmt) % (option, val) | |
) | |
def ensure_filename(self, option): | |
"""Ensure that 'option' is the name of an existing file.""" | |
self._ensure_tested_string( | |
option, os.path.isfile, "filename", "'%s' does not exist or is not a file" | |
) | |
def ensure_dirname(self, option): | |
self._ensure_tested_string( | |
option, | |
os.path.isdir, | |
"directory name", | |
"'%s' does not exist or is not a directory", | |
) | |
# -- Convenience methods for commands ------------------------------ | |
def get_command_name(self): | |
if hasattr(self, 'command_name'): | |
return self.command_name | |
else: | |
return self.__class__.__name__ | |
def set_undefined_options(self, src_cmd, *option_pairs): | |
"""Set the values of any "undefined" options from corresponding | |
option values in some other command object. "Undefined" here means | |
"is None", which is the convention used to indicate that an option | |
has not been changed between 'initialize_options()' and | |
'finalize_options()'. Usually called from 'finalize_options()' for | |
options that depend on some other command rather than another | |
option of the same command. 'src_cmd' is the other command from | |
which option values will be taken (a command object will be created | |
for it if necessary); the remaining arguments are | |
'(src_option,dst_option)' tuples which mean "take the value of | |
'src_option' in the 'src_cmd' command object, and copy it to | |
'dst_option' in the current command object". | |
""" | |
# Option_pairs: list of (src_option, dst_option) tuples | |
src_cmd_obj = self.distribution.get_command_obj(src_cmd) | |
src_cmd_obj.ensure_finalized() | |
for (src_option, dst_option) in option_pairs: | |
if getattr(self, dst_option) is None: | |
setattr(self, dst_option, getattr(src_cmd_obj, src_option)) | |
def get_finalized_command(self, command, create=1): | |
"""Wrapper around Distribution's 'get_command_obj()' method: find | |
(create if necessary and 'create' is true) the command object for | |
'command', call its 'ensure_finalized()' method, and return the | |
finalized command object. | |
""" | |
cmd_obj = self.distribution.get_command_obj(command, create) | |
cmd_obj.ensure_finalized() | |
return cmd_obj | |
# XXX rename to 'get_reinitialized_command()'? (should do the | |
# same in dist.py, if so) | |
def reinitialize_command(self, command, reinit_subcommands=0): | |
return self.distribution.reinitialize_command(command, reinit_subcommands) | |
def run_command(self, command): | |
"""Run some other command: uses the 'run_command()' method of | |
Distribution, which creates and finalizes the command object if | |
necessary and then invokes its 'run()' method. | |
""" | |
self.distribution.run_command(command) | |
def get_sub_commands(self): | |
"""Determine the sub-commands that are relevant in the current | |
distribution (ie., that need to be run). This is based on the | |
'sub_commands' class attribute: each tuple in that list may include | |
a method that we call to determine if the subcommand needs to be | |
run for the current distribution. Return a list of command names. | |
""" | |
commands = [] | |
for (cmd_name, method) in self.sub_commands: | |
if method is None or method(self): | |
commands.append(cmd_name) | |
return commands | |
# -- External world manipulation ----------------------------------- | |
def warn(self, msg): | |
log.warning("warning: %s: %s\n", self.get_command_name(), msg) | |
def execute(self, func, args, msg=None, level=1): | |
util.execute(func, args, msg, dry_run=self.dry_run) | |
def mkpath(self, name, mode=0o777): | |
dir_util.mkpath(name, mode, dry_run=self.dry_run) | |
def copy_file( | |
self, infile, outfile, preserve_mode=1, preserve_times=1, link=None, level=1 | |
): | |
"""Copy a file respecting verbose, dry-run and force flags. (The | |
former two default to whatever is in the Distribution object, and | |
the latter defaults to false for commands that don't define it.)""" | |
return file_util.copy_file( | |
infile, | |
outfile, | |
preserve_mode, | |
preserve_times, | |
not self.force, | |
link, | |
dry_run=self.dry_run, | |
) | |
def copy_tree( | |
self, | |
infile, | |
outfile, | |
preserve_mode=1, | |
preserve_times=1, | |
preserve_symlinks=0, | |
level=1, | |
): | |
"""Copy an entire directory tree respecting verbose, dry-run, | |
and force flags. | |
""" | |
return dir_util.copy_tree( | |
infile, | |
outfile, | |
preserve_mode, | |
preserve_times, | |
preserve_symlinks, | |
not self.force, | |
dry_run=self.dry_run, | |
) | |
def move_file(self, src, dst, level=1): | |
"""Move a file respecting dry-run flag.""" | |
return file_util.move_file(src, dst, dry_run=self.dry_run) | |
def spawn(self, cmd, search_path=1, level=1): | |
"""Spawn an external command respecting dry-run flag.""" | |
from distutils.spawn import spawn | |
spawn(cmd, search_path, dry_run=self.dry_run) | |
def make_archive( | |
self, base_name, format, root_dir=None, base_dir=None, owner=None, group=None | |
): | |
return archive_util.make_archive( | |
base_name, | |
format, | |
root_dir, | |
base_dir, | |
dry_run=self.dry_run, | |
owner=owner, | |
group=group, | |
) | |
def make_file( | |
self, infiles, outfile, func, args, exec_msg=None, skip_msg=None, level=1 | |
): | |
"""Special case of 'execute()' for operations that process one or | |
more input files and generate one output file. Works just like | |
'execute()', except the operation is skipped and a different | |
message printed if 'outfile' already exists and is newer than all | |
files listed in 'infiles'. If the command defined 'self.force', | |
and it is true, then the command is unconditionally run -- does no | |
timestamp checks. | |
""" | |
if skip_msg is None: | |
skip_msg = "skipping %s (inputs unchanged)" % outfile | |
# Allow 'infiles' to be a single string | |
if isinstance(infiles, str): | |
infiles = (infiles,) | |
elif not isinstance(infiles, (list, tuple)): | |
raise TypeError("'infiles' must be a string, or a list or tuple of strings") | |
if exec_msg is None: | |
exec_msg = "generating {} from {}".format(outfile, ', '.join(infiles)) | |
# If 'outfile' must be regenerated (either because it doesn't | |
# exist, is out-of-date, or the 'force' flag is true) then | |
# perform the action that presumably regenerates it | |
if self.force or dep_util.newer_group(infiles, outfile): | |
self.execute(func, args, exec_msg, level) | |
# Otherwise, print the "skip" message | |
else: | |
log.debug(skip_msg) | |