💾 Archived View for tris.fyi › pydoc › pkgutil captured on 2022-01-08 at 13:41:47. Gemini links have been rewritten to link to archived content
-=-=-=-=-=-=-
Utilities to support packages.
PEP 302 Finder that wraps Python's "classic" import algorithm
ImpImporter(dirname) produces a PEP 302 finder that searches that
directory. ImpImporter(None) produces a PEP 302 finder that searches
the current sys.path, plus any modules that are frozen or built-in.
Note that ImpImporter does not currently support being used by placement
on sys.meta_path.
find_module(self, fullname, path=None)
iter_modules(self, prefix='')
PEP 302 Loader that wraps Python's "classic" import algorithm
get_code(self, fullname=None)
get_data(self, pathname)
get_filename(self, fullname=None)
get_source(self, fullname=None)
is_package(self, fullname)
load_module(self, fullname)
code = None
source = None
A namedtuple with minimal info about a module.
count(self, value, /) Return number of occurrences of value.
index(self, value, start=0, stop=9223372036854775807, /) Return first index of value. Raises ValueError if the value is not present.
ispkg = _tuplegetter(2, 'Alias for field number 2') Alias for field number 2
module_finder = _tuplegetter(0, 'Alias for field number 0') Alias for field number 0
name = _tuplegetter(1, 'Alias for field number 1') Alias for field number 1
Create a module object. The name must be a string; the optional doc argument can have any type.
zipimporter(archivepath) -> zipimporter object
Create a new zipimporter instance. 'archivepath' must be a path to
a zipfile, or to a specific path inside a zipfile. For example, it can be
'/tmp/myimport.zip', or '/tmp/myimport.zip/mydirectory', if mydirectory is a
valid directory inside the archive.
'ZipImportError is raised if 'archivepath' doesn't point to a valid Zip
archive.
The 'archive' attribute of zipimporter objects contains the name of the
zipfile targeted.
find_loader(self, fullname, path=None)
find_loader(fullname, path=None) -> self, str or None.
Search for a module specified by 'fullname'. 'fullname' must be the
fully qualified (dotted) module name. It returns the zipimporter
instance itself if the module was found, a string containing the
full path name if it's possibly a portion of a namespace package,
or None otherwise. The optional 'path' argument is ignored -- it's
there for compatibility with the importer protocol.
find_module(self, fullname, path=None)
find_module(fullname, path=None) -> self or None.
Search for a module specified by 'fullname'. 'fullname' must be the
fully qualified (dotted) module name. It returns the zipimporter
instance itself if the module was found, or None if it wasn't.
The optional 'path' argument is ignored -- it's there for compatibility
with the importer protocol.
get_code(self, fullname)
get_code(fullname) -> code object.
Return the code object for the specified module. Raise ZipImportError
if the module couldn't be found.
get_data(self, pathname)
get_data(pathname) -> string with file data.
Return the data associated with 'pathname'. Raise OSError if
the file wasn't found.
get_filename(self, fullname)
get_filename(fullname) -> filename string.
Return the filename for the specified module.
get_resource_reader(self, fullname)
Return the ResourceReader for a package in a zip file.
If 'fullname' is a package within the zip file, return the
'ResourceReader' object for the package. Otherwise return None.
get_source(self, fullname)
get_source(fullname) -> source string.
Return the source code for the specified module. Raise ZipImportError
if the module couldn't be found, return None if the archive does
contain the module, but has no source for it.
is_package(self, fullname)
is_package(fullname) -> bool.
Return True if the module specified by fullname is a package.
Raise ZipImportError if the module couldn't be found.
load_module(self, fullname)
load_module(fullname) -> module.
Load the module specified by 'fullname'. 'fullname' must be the
fully qualified (dotted) module name. It returns the imported
module, or raises ZipImportError if it wasn't found.
extend_path(path, name)
Extend a package's path.
Intended use is to place the following code in a package's __init__.py:
from pkgutil import extend_path
__path__ = extend_path(__path__, __name__)
This will add to the package's __path__ all subdirectories of
directories on sys.path named after the package. This is useful
if one wants to distribute different parts of a single logical
package as multiple directories.
It also looks for *.pkg files beginning where * matches the name
argument. This feature is similar to *.pth files (see site.py),
except that it doesn't special-case lines starting with 'import'.
A *.pkg file is trusted at face value: apart from checking for
duplicates, all entries found in a *.pkg file are added to the
path, regardless of whether they are exist the filesystem. (This
is a feature.)
If the input path is not a list (as is the case for frozen
packages) it is returned unchanged. The input path is not
modified; an extended copy is returned. Items are only appended
to the copy at the end.
It is assumed that sys.path is a sequence. Items of sys.path that
are not (unicode or 8-bit) strings referring to existing
directories are ignored. Unicode items of sys.path that cause
errors when used as filenames may cause this function to raise an
exception (in line with os.path.isdir() behavior).
find_loader(fullname)
Find a "loader" object for fullname
This is a backwards compatibility wrapper around
importlib.util.find_spec that converts most failures to ImportError
and only returns the loader rather than the full spec
get_data(package, resource)
Get a resource from a package.
This is a wrapper round the PEP 302 loader get_data API. The package
argument should be the name of a package, in standard module format
(foo.bar). The resource argument should be in the form of a relative
filename, using '/' as the path separator. The parent directory name '..'
is not allowed, and nor is a rooted name (starting with a '/').
The function returns a binary string, which is the contents of the
specified resource.
For packages located in the filesystem, which have already been imported,
this is the rough equivalent of
d = os.path.dirname(sys.modules[package].__file__)
data = open(os.path.join(d, resource), 'rb').read()
If the package cannot be located or loaded, or it uses a PEP 302 loader
which does not support get_data(), then None is returned.
get_importer(path_item)
Retrieve a finder for the given path item
The returned finder is cached in sys.path_importer_cache
if it was newly created by a path hook.
The cache (or part of it) can be cleared manually if a
rescan of sys.path_hooks is necessary.
get_loader(module_or_name)
Get a "loader" object for module_or_name
Returns None if the module cannot be found or imported.
If the named module is not already imported, its containing package
(if any) is imported, in order to establish the package __path__.
iter_importer_modules(importer, prefix='')
iter_importers(fullname='')
Yield finders for the given module name
If fullname contains a '.', the finders will be for the package
containing fullname, otherwise they will be all registered top level
finders (i.e. those on both sys.meta_path and sys.path_hooks).
If the named module is in a package, that package is imported as a side
effect of invoking this function.
If no module name is specified, all top level finders are produced.
iter_modules(path=None, prefix='')
Yields ModuleInfo for all submodules on path,
or, if path is None, all top-level modules on sys.path.
'path' should be either None or a list of paths to look for
modules in.
'prefix' is a string to output on the front of every module name
on output.
iter_zipimport_modules(importer, prefix='')
namedtuple(typename, field_names, *, rename=False, defaults=None, module=None)
Returns a new subclass of tuple with named fields.
>>> Point = namedtuple('Point', ['x', 'y'])
>>> Point.__doc__ # docstring for the new class
'Point(x, y)'
>>> p = Point(11, y=22) # instantiate with positional args or keywords
>>> p[0] + p[1] # indexable like a plain tuple
33
>>> x, y = p # unpack like a regular tuple
>>> x, y
(11, 22)
>>> p.x + p.y # fields also accessible by name
33
>>> d = p._asdict() # convert to a dictionary
>>> d['x']
11
>>> Point(**d) # convert from a dictionary
Point(x=11, y=22)
>>> p._replace(x=100) # _replace() is like str.replace() but targets named fields
Point(x=100, y=22)
read_code(stream)
resolve_name(name)
Resolve a name to an object.
It is expected that `name` will be a string in one of the following
formats, where W is shorthand for a valid Python identifier and dot stands
for a literal period in these pseudo-regexes:
W(.W)*
W(.W)*:(W(.W)*)?
The first form is intended for backward compatibility only. It assumes that
some part of the dotted name is a package, and the rest is an object
somewhere within that package, possibly nested inside other objects.
Because the place where the package stops and the object hierarchy starts
can't be inferred by inspection, repeated attempts to import must be done
with this form.
In the second form, the caller makes the division point clear through the
provision of a single colon: the dotted name to the left of the colon is a
package to be imported, and the dotted name to the right is the object
hierarchy within that package. Only one import is needed in this form. If
it ends with the colon, then a module object is returned.
The function will return an object (which might be a module), or raise one
of the following exceptions:
ValueError - if `name` isn't in a recognised format
ImportError - if an import failed when it shouldn't have
AttributeError - if a failure occurred when traversing the object hierarchy
within the imported package to get to the desired object)
singledispatch(func)
Single-dispatch generic function decorator.
Transforms a function into a generic function, which can have different
behaviours depending upon the type of its first argument. The decorated
function acts as the default implementation, and additional
implementations can be registered using the register() attribute of the
generic function.
walk_packages(path=None, prefix='', onerror=None)
Yields ModuleInfo for all modules recursively
on path, or, if path is None, all accessible modules.
'path' should be either None or a list of paths to look for
modules in.
'prefix' is a string to output on the front of every module name
on output.
Note that this function must import all *packages* (NOT all
modules!) on the given path, in order to access the __path__
attribute to find submodules.
'onerror' is a function which gets called with one argument (the
name of the package which was being imported) if any exception
occurs while trying to import a package. If no onerror function is
supplied, ImportErrors are caught and ignored, while all other
exceptions are propagated, terminating the search.
Examples:
# list all modules python can access
walk_packages()
# list all submodules of ctypes
walk_packages(ctypes.__path__, ctypes.__name__+'.')