| 1 | """Utilities to support packages."""
|
| 2 |
|
| 3 | # NOTE: This module must remain compatible with Python 2.3, as it is shared
|
| 4 | # by setuptools for distribution with Python 2.3 and up.
|
| 5 |
|
| 6 | import os
|
| 7 | import sys
|
| 8 | import imp
|
| 9 | import os.path
|
| 10 | from types import ModuleType
|
| 11 |
|
| 12 | __all__ = [
|
| 13 | 'get_importer', 'iter_importers', 'get_loader', 'find_loader',
|
| 14 | 'walk_packages', 'iter_modules', 'get_data',
|
| 15 | 'ImpImporter', 'ImpLoader', 'read_code', 'extend_path',
|
| 16 | ]
|
| 17 |
|
| 18 | def read_code(stream):
|
| 19 | # This helper is needed in order for the PEP 302 emulation to
|
| 20 | # correctly handle compiled files
|
| 21 | import marshal
|
| 22 |
|
| 23 | magic = stream.read(4)
|
| 24 | if magic != imp.get_magic():
|
| 25 | return None
|
| 26 |
|
| 27 | stream.read(4) # Skip timestamp
|
| 28 | return marshal.load(stream)
|
| 29 |
|
| 30 |
|
| 31 | def simplegeneric(func):
|
| 32 | """Make a trivial single-dispatch generic function"""
|
| 33 | registry = {}
|
| 34 | def wrapper(*args, **kw):
|
| 35 | ob = args[0]
|
| 36 | try:
|
| 37 | cls = ob.__class__
|
| 38 | except AttributeError:
|
| 39 | cls = type(ob)
|
| 40 | try:
|
| 41 | mro = cls.__mro__
|
| 42 | except AttributeError:
|
| 43 | try:
|
| 44 | class cls(cls, object):
|
| 45 | pass
|
| 46 | mro = cls.__mro__[1:]
|
| 47 | except TypeError:
|
| 48 | mro = object, # must be an ExtensionClass or some such :(
|
| 49 | for t in mro:
|
| 50 | if t in registry:
|
| 51 | return registry[t](*args, **kw)
|
| 52 | else:
|
| 53 | return func(*args, **kw)
|
| 54 | try:
|
| 55 | wrapper.__name__ = func.__name__
|
| 56 | except (TypeError, AttributeError):
|
| 57 | pass # Python 2.3 doesn't allow functions to be renamed
|
| 58 |
|
| 59 | def register(typ, func=None):
|
| 60 | if func is None:
|
| 61 | return lambda f: register(typ, f)
|
| 62 | registry[typ] = func
|
| 63 | return func
|
| 64 |
|
| 65 | wrapper.__dict__ = func.__dict__
|
| 66 | wrapper.__doc__ = func.__doc__
|
| 67 | wrapper.register = register
|
| 68 | return wrapper
|
| 69 |
|
| 70 |
|
| 71 | def walk_packages(path=None, prefix='', onerror=None):
|
| 72 | """Yields (module_loader, name, ispkg) for all modules recursively
|
| 73 | on path, or, if path is None, all accessible modules.
|
| 74 |
|
| 75 | 'path' should be either None or a list of paths to look for
|
| 76 | modules in.
|
| 77 |
|
| 78 | 'prefix' is a string to output on the front of every module name
|
| 79 | on output.
|
| 80 |
|
| 81 | Note that this function must import all *packages* (NOT all
|
| 82 | modules!) on the given path, in order to access the __path__
|
| 83 | attribute to find submodules.
|
| 84 |
|
| 85 | 'onerror' is a function which gets called with one argument (the
|
| 86 | name of the package which was being imported) if any exception
|
| 87 | occurs while trying to import a package. If no onerror function is
|
| 88 | supplied, ImportErrors are caught and ignored, while all other
|
| 89 | exceptions are propagated, terminating the search.
|
| 90 |
|
| 91 | Examples:
|
| 92 |
|
| 93 | # list all modules python can access
|
| 94 | walk_packages()
|
| 95 |
|
| 96 | # list all submodules of ctypes
|
| 97 | walk_packages(ctypes.__path__, ctypes.__name__+'.')
|
| 98 | """
|
| 99 |
|
| 100 | def seen(p, m={}):
|
| 101 | if p in m:
|
| 102 | return True
|
| 103 | m[p] = True
|
| 104 |
|
| 105 | for importer, name, ispkg in iter_modules(path, prefix):
|
| 106 | yield importer, name, ispkg
|
| 107 |
|
| 108 | if ispkg:
|
| 109 | try:
|
| 110 | __import__(name)
|
| 111 | except ImportError:
|
| 112 | if onerror is not None:
|
| 113 | onerror(name)
|
| 114 | except Exception:
|
| 115 | if onerror is not None:
|
| 116 | onerror(name)
|
| 117 | else:
|
| 118 | raise
|
| 119 | else:
|
| 120 | path = getattr(sys.modules[name], '__path__', None) or []
|
| 121 |
|
| 122 | # don't traverse path items we've seen before
|
| 123 | path = [p for p in path if not seen(p)]
|
| 124 |
|
| 125 | for item in walk_packages(path, name+'.', onerror):
|
| 126 | yield item
|
| 127 |
|
| 128 |
|
| 129 | def iter_modules(path=None, prefix=''):
|
| 130 | """Yields (module_loader, name, ispkg) for all submodules on path,
|
| 131 | or, if path is None, all top-level modules on sys.path.
|
| 132 |
|
| 133 | 'path' should be either None or a list of paths to look for
|
| 134 | modules in.
|
| 135 |
|
| 136 | 'prefix' is a string to output on the front of every module name
|
| 137 | on output.
|
| 138 | """
|
| 139 |
|
| 140 | if path is None:
|
| 141 | importers = iter_importers()
|
| 142 | else:
|
| 143 | importers = map(get_importer, path)
|
| 144 |
|
| 145 | yielded = {}
|
| 146 | for i in importers:
|
| 147 | for name, ispkg in iter_importer_modules(i, prefix):
|
| 148 | if name not in yielded:
|
| 149 | yielded[name] = 1
|
| 150 | yield i, name, ispkg
|
| 151 |
|
| 152 |
|
| 153 | #@simplegeneric
|
| 154 | def iter_importer_modules(importer, prefix=''):
|
| 155 | if not hasattr(importer, 'iter_modules'):
|
| 156 | return []
|
| 157 | return importer.iter_modules(prefix)
|
| 158 |
|
| 159 | iter_importer_modules = simplegeneric(iter_importer_modules)
|
| 160 |
|
| 161 |
|
| 162 | class ImpImporter:
|
| 163 | """PEP 302 Importer that wraps Python's "classic" import algorithm
|
| 164 |
|
| 165 | ImpImporter(dirname) produces a PEP 302 importer that searches that
|
| 166 | directory. ImpImporter(None) produces a PEP 302 importer that searches
|
| 167 | the current sys.path, plus any modules that are frozen or built-in.
|
| 168 |
|
| 169 | Note that ImpImporter does not currently support being used by placement
|
| 170 | on sys.meta_path.
|
| 171 | """
|
| 172 |
|
| 173 | def __init__(self, path=None):
|
| 174 | self.path = path
|
| 175 |
|
| 176 | def find_module(self, fullname, path=None):
|
| 177 | # Note: we ignore 'path' argument since it is only used via meta_path
|
| 178 | subname = fullname.split(".")[-1]
|
| 179 | if subname != fullname and self.path is None:
|
| 180 | return None
|
| 181 | if self.path is None:
|
| 182 | path = None
|
| 183 | else:
|
| 184 | path = [os.path.realpath(self.path)]
|
| 185 | try:
|
| 186 | file, filename, etc = imp.find_module(subname, path)
|
| 187 | except ImportError:
|
| 188 | return None
|
| 189 | return ImpLoader(fullname, file, filename, etc)
|
| 190 |
|
| 191 | def iter_modules(self, prefix=''):
|
| 192 | if self.path is None or not os.path.isdir(self.path):
|
| 193 | return
|
| 194 |
|
| 195 | yielded = {}
|
| 196 | import inspect
|
| 197 | try:
|
| 198 | filenames = os.listdir(self.path)
|
| 199 | except OSError:
|
| 200 | # ignore unreadable directories like import does
|
| 201 | filenames = []
|
| 202 | filenames.sort() # handle packages before same-named modules
|
| 203 |
|
| 204 | for fn in filenames:
|
| 205 | modname = inspect.getmodulename(fn)
|
| 206 | if modname=='__init__' or modname in yielded:
|
| 207 | continue
|
| 208 |
|
| 209 | path = os.path.join(self.path, fn)
|
| 210 | ispkg = False
|
| 211 |
|
| 212 | if not modname and os.path.isdir(path) and '.' not in fn:
|
| 213 | modname = fn
|
| 214 | try:
|
| 215 | dircontents = os.listdir(path)
|
| 216 | except OSError:
|
| 217 | # ignore unreadable directories like import does
|
| 218 | dircontents = []
|
| 219 | for fn in dircontents:
|
| 220 | subname = inspect.getmodulename(fn)
|
| 221 | if subname=='__init__':
|
| 222 | ispkg = True
|
| 223 | break
|
| 224 | else:
|
| 225 | continue # not a package
|
| 226 |
|
| 227 | if modname and '.' not in modname:
|
| 228 | yielded[modname] = 1
|
| 229 | yield prefix + modname, ispkg
|
| 230 |
|
| 231 |
|
| 232 | class ImpLoader:
|
| 233 | """PEP 302 Loader that wraps Python's "classic" import algorithm
|
| 234 | """
|
| 235 | code = source = None
|
| 236 |
|
| 237 | def __init__(self, fullname, file, filename, etc):
|
| 238 | self.file = file
|
| 239 | self.filename = filename
|
| 240 | self.fullname = fullname
|
| 241 | self.etc = etc
|
| 242 |
|
| 243 | def load_module(self, fullname):
|
| 244 | self._reopen()
|
| 245 | try:
|
| 246 | mod = imp.load_module(fullname, self.file, self.filename, self.etc)
|
| 247 | finally:
|
| 248 | if self.file:
|
| 249 | self.file.close()
|
| 250 | # Note: we don't set __loader__ because we want the module to look
|
| 251 | # normal; i.e. this is just a wrapper for standard import machinery
|
| 252 | return mod
|
| 253 |
|
| 254 | def get_data(self, pathname):
|
| 255 | return open(pathname, "rb").read()
|
| 256 |
|
| 257 | def _reopen(self):
|
| 258 | if self.file and self.file.closed:
|
| 259 | mod_type = self.etc[2]
|
| 260 | if mod_type==imp.PY_SOURCE:
|
| 261 | self.file = open(self.filename, 'rU')
|
| 262 | elif mod_type in (imp.PY_COMPILED, imp.C_EXTENSION):
|
| 263 | self.file = open(self.filename, 'rb')
|
| 264 |
|
| 265 | def _fix_name(self, fullname):
|
| 266 | if fullname is None:
|
| 267 | fullname = self.fullname
|
| 268 | elif fullname != self.fullname:
|
| 269 | raise ImportError("Loader for module %s cannot handle "
|
| 270 | "module %s" % (self.fullname, fullname))
|
| 271 | return fullname
|
| 272 |
|
| 273 | def is_package(self, fullname):
|
| 274 | fullname = self._fix_name(fullname)
|
| 275 | return self.etc[2]==imp.PKG_DIRECTORY
|
| 276 |
|
| 277 | def get_code(self, fullname=None):
|
| 278 | fullname = self._fix_name(fullname)
|
| 279 | if self.code is None:
|
| 280 | mod_type = self.etc[2]
|
| 281 | if mod_type==imp.PY_SOURCE:
|
| 282 | source = self.get_source(fullname)
|
| 283 | self.code = compile(source, self.filename, 'exec')
|
| 284 | elif mod_type==imp.PY_COMPILED:
|
| 285 | self._reopen()
|
| 286 | try:
|
| 287 | self.code = read_code(self.file)
|
| 288 | finally:
|
| 289 | self.file.close()
|
| 290 | elif mod_type==imp.PKG_DIRECTORY:
|
| 291 | self.code = self._get_delegate().get_code()
|
| 292 | return self.code
|
| 293 |
|
| 294 | def get_source(self, fullname=None):
|
| 295 | fullname = self._fix_name(fullname)
|
| 296 | if self.source is None:
|
| 297 | mod_type = self.etc[2]
|
| 298 | if mod_type==imp.PY_SOURCE:
|
| 299 | self._reopen()
|
| 300 | try:
|
| 301 | self.source = self.file.read()
|
| 302 | finally:
|
| 303 | self.file.close()
|
| 304 | elif mod_type==imp.PY_COMPILED:
|
| 305 | if os.path.exists(self.filename[:-1]):
|
| 306 | f = open(self.filename[:-1], 'rU')
|
| 307 | self.source = f.read()
|
| 308 | f.close()
|
| 309 | elif mod_type==imp.PKG_DIRECTORY:
|
| 310 | self.source = self._get_delegate().get_source()
|
| 311 | return self.source
|
| 312 |
|
| 313 |
|
| 314 | def _get_delegate(self):
|
| 315 | return ImpImporter(self.filename).find_module('__init__')
|
| 316 |
|
| 317 | def get_filename(self, fullname=None):
|
| 318 | fullname = self._fix_name(fullname)
|
| 319 | mod_type = self.etc[2]
|
| 320 | if self.etc[2]==imp.PKG_DIRECTORY:
|
| 321 | return self._get_delegate().get_filename()
|
| 322 | elif self.etc[2] in (imp.PY_SOURCE, imp.PY_COMPILED, imp.C_EXTENSION):
|
| 323 | return self.filename
|
| 324 | return None
|
| 325 |
|
| 326 |
|
| 327 | try:
|
| 328 | import zipimport
|
| 329 | from zipimport import zipimporter
|
| 330 |
|
| 331 | def iter_zipimport_modules(importer, prefix=''):
|
| 332 | dirlist = zipimport._zip_directory_cache[importer.archive].keys()
|
| 333 | dirlist.sort()
|
| 334 | _prefix = importer.prefix
|
| 335 | plen = len(_prefix)
|
| 336 | yielded = {}
|
| 337 | import inspect
|
| 338 | for fn in dirlist:
|
| 339 | if not fn.startswith(_prefix):
|
| 340 | continue
|
| 341 |
|
| 342 | fn = fn[plen:].split(os.sep)
|
| 343 |
|
| 344 | if len(fn)==2 and fn[1].startswith('__init__.py'):
|
| 345 | if fn[0] not in yielded:
|
| 346 | yielded[fn[0]] = 1
|
| 347 | yield fn[0], True
|
| 348 |
|
| 349 | if len(fn)!=1:
|
| 350 | continue
|
| 351 |
|
| 352 | modname = inspect.getmodulename(fn[0])
|
| 353 | if modname=='__init__':
|
| 354 | continue
|
| 355 |
|
| 356 | if modname and '.' not in modname and modname not in yielded:
|
| 357 | yielded[modname] = 1
|
| 358 | yield prefix + modname, False
|
| 359 |
|
| 360 | iter_importer_modules.register(zipimporter, iter_zipimport_modules)
|
| 361 |
|
| 362 | except ImportError:
|
| 363 | pass
|
| 364 |
|
| 365 |
|
| 366 | def get_importer(path_item):
|
| 367 | """Retrieve a PEP 302 importer for the given path item
|
| 368 |
|
| 369 | The returned importer is cached in sys.path_importer_cache
|
| 370 | if it was newly created by a path hook.
|
| 371 |
|
| 372 | If there is no importer, a wrapper around the basic import
|
| 373 | machinery is returned. This wrapper is never inserted into
|
| 374 | the importer cache (None is inserted instead).
|
| 375 |
|
| 376 | The cache (or part of it) can be cleared manually if a
|
| 377 | rescan of sys.path_hooks is necessary.
|
| 378 | """
|
| 379 | try:
|
| 380 | importer = sys.path_importer_cache[path_item]
|
| 381 | except KeyError:
|
| 382 | for path_hook in sys.path_hooks:
|
| 383 | try:
|
| 384 | importer = path_hook(path_item)
|
| 385 | break
|
| 386 | except ImportError:
|
| 387 | pass
|
| 388 | else:
|
| 389 | importer = None
|
| 390 | sys.path_importer_cache.setdefault(path_item, importer)
|
| 391 |
|
| 392 | if importer is None:
|
| 393 | try:
|
| 394 | importer = ImpImporter(path_item)
|
| 395 | except ImportError:
|
| 396 | importer = None
|
| 397 | return importer
|
| 398 |
|
| 399 |
|
| 400 | def iter_importers(fullname=""):
|
| 401 | """Yield PEP 302 importers for the given module name
|
| 402 |
|
| 403 | If fullname contains a '.', the importers will be for the package
|
| 404 | containing fullname, otherwise they will be importers for sys.meta_path,
|
| 405 | sys.path, and Python's "classic" import machinery, in that order. If
|
| 406 | the named module is in a package, that package is imported as a side
|
| 407 | effect of invoking this function.
|
| 408 |
|
| 409 | Non PEP 302 mechanisms (e.g. the Windows registry) used by the
|
| 410 | standard import machinery to find files in alternative locations
|
| 411 | are partially supported, but are searched AFTER sys.path. Normally,
|
| 412 | these locations are searched BEFORE sys.path, preventing sys.path
|
| 413 | entries from shadowing them.
|
| 414 |
|
| 415 | For this to cause a visible difference in behaviour, there must
|
| 416 | be a module or package name that is accessible via both sys.path
|
| 417 | and one of the non PEP 302 file system mechanisms. In this case,
|
| 418 | the emulation will find the former version, while the builtin
|
| 419 | import mechanism will find the latter.
|
| 420 |
|
| 421 | Items of the following types can be affected by this discrepancy:
|
| 422 | imp.C_EXTENSION, imp.PY_SOURCE, imp.PY_COMPILED, imp.PKG_DIRECTORY
|
| 423 | """
|
| 424 | if fullname.startswith('.'):
|
| 425 | raise ImportError("Relative module names not supported")
|
| 426 | if '.' in fullname:
|
| 427 | # Get the containing package's __path__
|
| 428 | pkg = '.'.join(fullname.split('.')[:-1])
|
| 429 | if pkg not in sys.modules:
|
| 430 | __import__(pkg)
|
| 431 | path = getattr(sys.modules[pkg], '__path__', None) or []
|
| 432 | else:
|
| 433 | for importer in sys.meta_path:
|
| 434 | yield importer
|
| 435 | path = sys.path
|
| 436 | for item in path:
|
| 437 | yield get_importer(item)
|
| 438 | if '.' not in fullname:
|
| 439 | yield ImpImporter()
|
| 440 |
|
| 441 | def get_loader(module_or_name):
|
| 442 | """Get a PEP 302 "loader" object for module_or_name
|
| 443 |
|
| 444 | If the module or package is accessible via the normal import
|
| 445 | mechanism, a wrapper around the relevant part of that machinery
|
| 446 | is returned. Returns None if the module cannot be found or imported.
|
| 447 | If the named module is not already imported, its containing package
|
| 448 | (if any) is imported, in order to establish the package __path__.
|
| 449 |
|
| 450 | This function uses iter_importers(), and is thus subject to the same
|
| 451 | limitations regarding platform-specific special import locations such
|
| 452 | as the Windows registry.
|
| 453 | """
|
| 454 | if module_or_name in sys.modules:
|
| 455 | module_or_name = sys.modules[module_or_name]
|
| 456 | if isinstance(module_or_name, ModuleType):
|
| 457 | module = module_or_name
|
| 458 | loader = getattr(module, '__loader__', None)
|
| 459 | if loader is not None:
|
| 460 | return loader
|
| 461 | fullname = module.__name__
|
| 462 | else:
|
| 463 | fullname = module_or_name
|
| 464 | return find_loader(fullname)
|
| 465 |
|
| 466 | def find_loader(fullname):
|
| 467 | """Find a PEP 302 "loader" object for fullname
|
| 468 |
|
| 469 | If fullname contains dots, path must be the containing package's __path__.
|
| 470 | Returns None if the module cannot be found or imported. This function uses
|
| 471 | iter_importers(), and is thus subject to the same limitations regarding
|
| 472 | platform-specific special import locations such as the Windows registry.
|
| 473 | """
|
| 474 | for importer in iter_importers(fullname):
|
| 475 | loader = importer.find_module(fullname)
|
| 476 | if loader is not None:
|
| 477 | return loader
|
| 478 |
|
| 479 | return None
|
| 480 |
|
| 481 |
|
| 482 | def extend_path(path, name):
|
| 483 | """Extend a package's path.
|
| 484 |
|
| 485 | Intended use is to place the following code in a package's __init__.py:
|
| 486 |
|
| 487 | from pkgutil import extend_path
|
| 488 | __path__ = extend_path(__path__, __name__)
|
| 489 |
|
| 490 | This will add to the package's __path__ all subdirectories of
|
| 491 | directories on sys.path named after the package. This is useful
|
| 492 | if one wants to distribute different parts of a single logical
|
| 493 | package as multiple directories.
|
| 494 |
|
| 495 | It also looks for *.pkg files beginning where * matches the name
|
| 496 | argument. This feature is similar to *.pth files (see site.py),
|
| 497 | except that it doesn't special-case lines starting with 'import'.
|
| 498 | A *.pkg file is trusted at face value: apart from checking for
|
| 499 | duplicates, all entries found in a *.pkg file are added to the
|
| 500 | path, regardless of whether they are exist the filesystem. (This
|
| 501 | is a feature.)
|
| 502 |
|
| 503 | If the input path is not a list (as is the case for frozen
|
| 504 | packages) it is returned unchanged. The input path is not
|
| 505 | modified; an extended copy is returned. Items are only appended
|
| 506 | to the copy at the end.
|
| 507 |
|
| 508 | It is assumed that sys.path is a sequence. Items of sys.path that
|
| 509 | are not (unicode or 8-bit) strings referring to existing
|
| 510 | directories are ignored. Unicode items of sys.path that cause
|
| 511 | errors when used as filenames may cause this function to raise an
|
| 512 | exception (in line with os.path.isdir() behavior).
|
| 513 | """
|
| 514 |
|
| 515 | if not isinstance(path, list):
|
| 516 | # This could happen e.g. when this is called from inside a
|
| 517 | # frozen package. Return the path unchanged in that case.
|
| 518 | return path
|
| 519 |
|
| 520 | pname = os.path.join(*name.split('.')) # Reconstitute as relative path
|
| 521 | # Just in case os.extsep != '.'
|
| 522 | sname = os.extsep.join(name.split('.'))
|
| 523 | sname_pkg = sname + os.extsep + "pkg"
|
| 524 | init_py = "__init__" + os.extsep + "py"
|
| 525 |
|
| 526 | path = path[:] # Start with a copy of the existing path
|
| 527 |
|
| 528 | for dir in sys.path:
|
| 529 | if not isinstance(dir, basestring) or not os.path.isdir(dir):
|
| 530 | continue
|
| 531 | subdir = os.path.join(dir, pname)
|
| 532 | # XXX This may still add duplicate entries to path on
|
| 533 | # case-insensitive filesystems
|
| 534 | initfile = os.path.join(subdir, init_py)
|
| 535 | if subdir not in path and os.path.isfile(initfile):
|
| 536 | path.append(subdir)
|
| 537 | # XXX Is this the right thing for subpackages like zope.app?
|
| 538 | # It looks for a file named "zope.app.pkg"
|
| 539 | pkgfile = os.path.join(dir, sname_pkg)
|
| 540 | if os.path.isfile(pkgfile):
|
| 541 | try:
|
| 542 | f = open(pkgfile)
|
| 543 | except IOError, msg:
|
| 544 | sys.stderr.write("Can't open %s: %s\n" %
|
| 545 | (pkgfile, msg))
|
| 546 | else:
|
| 547 | for line in f:
|
| 548 | line = line.rstrip('\n')
|
| 549 | if not line or line.startswith('#'):
|
| 550 | continue
|
| 551 | path.append(line) # Don't check for existence!
|
| 552 | f.close()
|
| 553 |
|
| 554 | return path
|
| 555 |
|
| 556 | def get_data(package, resource):
|
| 557 | """Get a resource from a package.
|
| 558 |
|
| 559 | This is a wrapper round the PEP 302 loader get_data API. The package
|
| 560 | argument should be the name of a package, in standard module format
|
| 561 | (foo.bar). The resource argument should be in the form of a relative
|
| 562 | filename, using '/' as the path separator. The parent directory name '..'
|
| 563 | is not allowed, and nor is a rooted name (starting with a '/').
|
| 564 |
|
| 565 | The function returns a binary string, which is the contents of the
|
| 566 | specified resource.
|
| 567 |
|
| 568 | For packages located in the filesystem, which have already been imported,
|
| 569 | this is the rough equivalent of
|
| 570 |
|
| 571 | d = os.path.dirname(sys.modules[package].__file__)
|
| 572 | data = open(os.path.join(d, resource), 'rb').read()
|
| 573 |
|
| 574 | If the package cannot be located or loaded, or it uses a PEP 302 loader
|
| 575 | which does not support get_data(), then None is returned.
|
| 576 | """
|
| 577 |
|
| 578 | loader = get_loader(package)
|
| 579 | if loader is None or not hasattr(loader, 'get_data'):
|
| 580 | return None
|
| 581 | mod = sys.modules.get(package) or loader.load_module(package)
|
| 582 | if mod is None or not hasattr(mod, '__file__'):
|
| 583 | return None
|
| 584 |
|
| 585 | # Modify the resource name to be compatible with the loader.get_data
|
| 586 | # signature - an os.path format "filename" starting with the dirname of
|
| 587 | # the package's __file__
|
| 588 | parts = resource.split('/')
|
| 589 | parts.insert(0, os.path.dirname(mod.__file__))
|
| 590 | resource_name = os.path.join(*parts)
|
| 591 | return loader.get_data(resource_name)
|