1"""distutils.cmd 2 3Provides the Command class, the base class for the command classes 4in the distutils.command package. 5""" 6 7import sys, os, re 8from distutils.errors import DistutilsOptionError 9from distutils import util, dir_util, file_util, archive_util, dep_util 10from distutils import log 11 12class Command: 13 """Abstract base class for defining command classes, the "worker bees" 14 of the Distutils. A useful analogy for command classes is to think of 15 them as subroutines with local variables called "options". The options 16 are "declared" in 'initialize_options()' and "defined" (given their 17 final values, aka "finalized") in 'finalize_options()', both of which 18 must be defined by every command class. The distinction between the 19 two is necessary because option values might come from the outside 20 world (command line, config file, ...), and any options dependent on 21 other options must be computed *after* these outside influences have 22 been processed -- hence 'finalize_options()'. The "body" of the 23 subroutine, where it does all its work based on the values of its 24 options, is the 'run()' method, which must also be implemented by every 25 command class. 26 """ 27 28 # 'sub_commands' formalizes the notion of a "family" of commands, 29 # eg. "install" as the parent with sub-commands "install_lib", 30 # "install_headers", etc. The parent of a family of commands 31 # defines 'sub_commands' as a class attribute; it's a list of 32 # (command_name : string, predicate : unbound_method | string | None) 33 # tuples, where 'predicate' is a method of the parent command that 34 # determines whether the corresponding command is applicable in the 35 # current situation. (Eg. we "install_headers" is only applicable if 36 # we have any C header files to install.) If 'predicate' is None, 37 # that command is always applicable. 38 # 39 # 'sub_commands' is usually defined at the *end* of a class, because 40 # predicates can be unbound methods, so they must already have been 41 # defined. The canonical example is the "install" command. 42 sub_commands = [] 43 44 45 # -- Creation/initialization methods ------------------------------- 46 47 def __init__(self, dist): 48 """Create and initialize a new Command object. Most importantly, 49 invokes the 'initialize_options()' method, which is the real 50 initializer and depends on the actual command being 51 instantiated. 52 """ 53 # late import because of mutual dependence between these classes 54 from distutils.dist import Distribution 55 56 if not isinstance(dist, Distribution): 57 raise TypeError("dist must be a Distribution instance") 58 if self.__class__ is Command: 59 raise RuntimeError("Command is an abstract class") 60 61 self.distribution = dist 62 self.initialize_options() 63 64 # Per-command versions of the global flags, so that the user can 65 # customize Distutils' behaviour command-by-command and let some 66 # commands fall back on the Distribution's behaviour. None means 67 # "not defined, check self.distribution's copy", while 0 or 1 mean 68 # false and true (duh). Note that this means figuring out the real 69 # value of each flag is a touch complicated -- hence "self._dry_run" 70 # will be handled by __getattr__, below. 71 # XXX This needs to be fixed. 72 self._dry_run = None 73 74 # verbose is largely ignored, but needs to be set for 75 # backwards compatibility (I think)? 76 self.verbose = dist.verbose 77 78 # Some commands define a 'self.force' option to ignore file 79 # timestamps, but methods defined *here* assume that 80 # 'self.force' exists for all commands. So define it here 81 # just to be safe. 82 self.force = None 83 84 # The 'help' flag is just used for command-line parsing, so 85 # none of that complicated bureaucracy is needed. 86 self.help = 0 87 88 # 'finalized' records whether or not 'finalize_options()' has been 89 # called. 'finalize_options()' itself should not pay attention to 90 # this flag: it is the business of 'ensure_finalized()', which 91 # always calls 'finalize_options()', to respect/update it. 92 self.finalized = 0 93 94 # XXX A more explicit way to customize dry_run would be better. 95 def __getattr__(self, attr): 96 if attr == 'dry_run': 97 myval = getattr(self, "_" + attr) 98 if myval is None: 99 return getattr(self.distribution, attr) 100 else: 101 return myval 102 else: 103 raise AttributeError(attr) 104 105 def ensure_finalized(self): 106 if not self.finalized: 107 self.finalize_options() 108 self.finalized = 1 109 110 # Subclasses must define: 111 # initialize_options() 112 # provide default values for all options; may be customized by 113 # setup script, by options from config file(s), or by command-line 114 # options 115 # finalize_options() 116 # decide on the final values for all options; this is called 117 # after all possible intervention from the outside world 118 # (command-line, option file, etc.) has been processed 119 # run() 120 # run the command: do whatever it is we're here to do, 121 # controlled by the command's various option values 122 123 def initialize_options(self): 124 """Set default values for all the options that this command 125 supports. Note that these defaults may be overridden by other 126 commands, by the setup script, by config files, or by the 127 command-line. Thus, this is not the place to code dependencies 128 between options; generally, 'initialize_options()' implementations 129 are just a bunch of "self.foo = None" assignments. 130 131 This method must be implemented by all command classes. 132 """ 133 raise RuntimeError("abstract method -- subclass %s must override" 134 % self.__class__) 135 136 def finalize_options(self): 137 """Set final values for all the options that this command supports. 138 This is always called as late as possible, ie. after any option 139 assignments from the command-line or from other commands have been 140 done. Thus, this is the place to code option dependencies: if 141 'foo' depends on 'bar', then it is safe to set 'foo' from 'bar' as 142 long as 'foo' still has the same value it was assigned in 143 'initialize_options()'. 144 145 This method must be implemented by all command classes. 146 """ 147 raise RuntimeError("abstract method -- subclass %s must override" 148 % self.__class__) 149 150 151 def dump_options(self, header=None, indent=""): 152 from distutils.fancy_getopt import longopt_xlate 153 if header is None: 154 header = "command options for '%s':" % self.get_command_name() 155 self.announce(indent + header, level=log.INFO) 156 indent = indent + " " 157 for (option, _, _) in self.user_options: 158 option = option.translate(longopt_xlate) 159 if option[-1] == "=": 160 option = option[:-1] 161 value = getattr(self, option) 162 self.announce(indent + "%s = %s" % (option, value), 163 level=log.INFO) 164 165 def run(self): 166 """A command's raison d'etre: carry out the action it exists to 167 perform, controlled by the options initialized in 168 'initialize_options()', customized by other commands, the setup 169 script, the command-line, and config files, and finalized in 170 'finalize_options()'. All terminal output and filesystem 171 interaction should be done by 'run()'. 172 173 This method must be implemented by all command classes. 174 """ 175 raise RuntimeError("abstract method -- subclass %s must override" 176 % self.__class__) 177 178 def announce(self, msg, level=1): 179 """If the current verbosity level is of greater than or equal to 180 'level' print 'msg' to stdout. 181 """ 182 log.log(level, msg) 183 184 def debug_print(self, msg): 185 """Print 'msg' to stdout if the global DEBUG (taken from the 186 DISTUTILS_DEBUG environment variable) flag is true. 187 """ 188 from distutils.debug import DEBUG 189 if DEBUG: 190 print(msg) 191 sys.stdout.flush() 192 193 194 # -- Option validation methods ------------------------------------- 195 # (these are very handy in writing the 'finalize_options()' method) 196 # 197 # NB. the general philosophy here is to ensure that a particular option 198 # value meets certain type and value constraints. If not, we try to 199 # force it into conformance (eg. if we expect a list but have a string, 200 # split the string on comma and/or whitespace). If we can't force the 201 # option into conformance, raise DistutilsOptionError. Thus, command 202 # classes need do nothing more than (eg.) 203 # self.ensure_string_list('foo') 204 # and they can be guaranteed that thereafter, self.foo will be 205 # a list of strings. 206 207 def _ensure_stringlike(self, option, what, default=None): 208 val = getattr(self, option) 209 if val is None: 210 setattr(self, option, default) 211 return default 212 elif not isinstance(val, str): 213 raise DistutilsOptionError("'%s' must be a %s (got `%s`)" 214 % (option, what, val)) 215 return val 216 217 def ensure_string(self, option, default=None): 218 """Ensure that 'option' is a string; if not defined, set it to 219 'default'. 220 """ 221 self._ensure_stringlike(option, "string", default) 222 223 def ensure_string_list(self, option): 224 r"""Ensure that 'option' is a list of strings. If 'option' is 225 currently a string, we split it either on /,\s*/ or /\s+/, so 226 "foo bar baz", "foo,bar,baz", and "foo, bar baz" all become 227 ["foo", "bar", "baz"]. 228 """ 229 val = getattr(self, option) 230 if val is None: 231 return 232 elif isinstance(val, str): 233 setattr(self, option, re.split(r',\s*|\s+', val)) 234 else: 235 if isinstance(val, list): 236 ok = all(isinstance(v, str) for v in val) 237 else: 238 ok = False 239 if not ok: 240 raise DistutilsOptionError( 241 "'%s' must be a list of strings (got %r)" 242 % (option, val)) 243 244 def _ensure_tested_string(self, option, tester, what, error_fmt, 245 default=None): 246 val = self._ensure_stringlike(option, what, default) 247 if val is not None and not tester(val): 248 raise DistutilsOptionError(("error in '%s' option: " + error_fmt) 249 % (option, val)) 250 251 def ensure_filename(self, option): 252 """Ensure that 'option' is the name of an existing file.""" 253 self._ensure_tested_string(option, os.path.isfile, 254 "filename", 255 "'%s' does not exist or is not a file") 256 257 def ensure_dirname(self, option): 258 self._ensure_tested_string(option, os.path.isdir, 259 "directory name", 260 "'%s' does not exist or is not a directory") 261 262 263 # -- Convenience methods for commands ------------------------------ 264 265 def get_command_name(self): 266 if hasattr(self, 'command_name'): 267 return self.command_name 268 else: 269 return self.__class__.__name__ 270 271 def set_undefined_options(self, src_cmd, *option_pairs): 272 """Set the values of any "undefined" options from corresponding 273 option values in some other command object. "Undefined" here means 274 "is None", which is the convention used to indicate that an option 275 has not been changed between 'initialize_options()' and 276 'finalize_options()'. Usually called from 'finalize_options()' for 277 options that depend on some other command rather than another 278 option of the same command. 'src_cmd' is the other command from 279 which option values will be taken (a command object will be created 280 for it if necessary); the remaining arguments are 281 '(src_option,dst_option)' tuples which mean "take the value of 282 'src_option' in the 'src_cmd' command object, and copy it to 283 'dst_option' in the current command object". 284 """ 285 # Option_pairs: list of (src_option, dst_option) tuples 286 src_cmd_obj = self.distribution.get_command_obj(src_cmd) 287 src_cmd_obj.ensure_finalized() 288 for (src_option, dst_option) in option_pairs: 289 if getattr(self, dst_option) is None: 290 setattr(self, dst_option, getattr(src_cmd_obj, src_option)) 291 292 def get_finalized_command(self, command, create=1): 293 """Wrapper around Distribution's 'get_command_obj()' method: find 294 (create if necessary and 'create' is true) the command object for 295 'command', call its 'ensure_finalized()' method, and return the 296 finalized command object. 297 """ 298 cmd_obj = self.distribution.get_command_obj(command, create) 299 cmd_obj.ensure_finalized() 300 return cmd_obj 301 302 # XXX rename to 'get_reinitialized_command()'? (should do the 303 # same in dist.py, if so) 304 def reinitialize_command(self, command, reinit_subcommands=0): 305 return self.distribution.reinitialize_command(command, 306 reinit_subcommands) 307 308 def run_command(self, command): 309 """Run some other command: uses the 'run_command()' method of 310 Distribution, which creates and finalizes the command object if 311 necessary and then invokes its 'run()' method. 312 """ 313 self.distribution.run_command(command) 314 315 def get_sub_commands(self): 316 """Determine the sub-commands that are relevant in the current 317 distribution (ie., that need to be run). This is based on the 318 'sub_commands' class attribute: each tuple in that list may include 319 a method that we call to determine if the subcommand needs to be 320 run for the current distribution. Return a list of command names. 321 """ 322 commands = [] 323 for (cmd_name, method) in self.sub_commands: 324 if method is None or method(self): 325 commands.append(cmd_name) 326 return commands 327 328 329 # -- External world manipulation ----------------------------------- 330 331 def warn(self, msg): 332 log.warn("warning: %s: %s\n", self.get_command_name(), msg) 333 334 def execute(self, func, args, msg=None, level=1): 335 util.execute(func, args, msg, dry_run=self.dry_run) 336 337 def mkpath(self, name, mode=0o777): 338 dir_util.mkpath(name, mode, dry_run=self.dry_run) 339 340 def copy_file(self, infile, outfile, preserve_mode=1, preserve_times=1, 341 link=None, level=1): 342 """Copy a file respecting verbose, dry-run and force flags. (The 343 former two default to whatever is in the Distribution object, and 344 the latter defaults to false for commands that don't define it.)""" 345 return file_util.copy_file(infile, outfile, preserve_mode, 346 preserve_times, not self.force, link, 347 dry_run=self.dry_run) 348 349 def copy_tree(self, infile, outfile, preserve_mode=1, preserve_times=1, 350 preserve_symlinks=0, level=1): 351 """Copy an entire directory tree respecting verbose, dry-run, 352 and force flags. 353 """ 354 return dir_util.copy_tree(infile, outfile, preserve_mode, 355 preserve_times, preserve_symlinks, 356 not self.force, dry_run=self.dry_run) 357 358 def move_file (self, src, dst, level=1): 359 """Move a file respecting dry-run flag.""" 360 return file_util.move_file(src, dst, dry_run=self.dry_run) 361 362 def spawn(self, cmd, search_path=1, level=1): 363 """Spawn an external command respecting dry-run flag.""" 364 from distutils.spawn import spawn 365 spawn(cmd, search_path, dry_run=self.dry_run) 366 367 def make_archive(self, base_name, format, root_dir=None, base_dir=None, 368 owner=None, group=None): 369 return archive_util.make_archive(base_name, format, root_dir, base_dir, 370 dry_run=self.dry_run, 371 owner=owner, group=group) 372 373 def make_file(self, infiles, outfile, func, args, 374 exec_msg=None, skip_msg=None, level=1): 375 """Special case of 'execute()' for operations that process one or 376 more input files and generate one output file. Works just like 377 'execute()', except the operation is skipped and a different 378 message printed if 'outfile' already exists and is newer than all 379 files listed in 'infiles'. If the command defined 'self.force', 380 and it is true, then the command is unconditionally run -- does no 381 timestamp checks. 382 """ 383 if skip_msg is None: 384 skip_msg = "skipping %s (inputs unchanged)" % outfile 385 386 # Allow 'infiles' to be a single string 387 if isinstance(infiles, str): 388 infiles = (infiles,) 389 elif not isinstance(infiles, (list, tuple)): 390 raise TypeError( 391 "'infiles' must be a string, or a list or tuple of strings") 392 393 if exec_msg is None: 394 exec_msg = "generating %s from %s" % (outfile, ', '.join(infiles)) 395 396 # If 'outfile' must be regenerated (either because it doesn't 397 # exist, is out-of-date, or the 'force' flag is true) then 398 # perform the action that presumably regenerates it 399 if self.force or dep_util.newer_group(infiles, outfile): 400 self.execute(func, args, exec_msg, level) 401 # Otherwise, print the "skip" message 402 else: 403 log.debug(skip_msg) 404