How can I get a list of all classes within current module in Python

Question

I ve seen plenty of examples of people extracting all of the classes from a module  usually something like     foo py class Foo      pass    test py import inspect import foo  for name  obj in inspect getmembers foo       if inspect isclass obj           print obj   Awesome   But I can t find out how to get all of the classes from the current module     foo py import inspect  class Foo      pass  def print classes        for name  obj in inspect getmembers         what do I do here          if inspect isclass obj               print obj    test py import foo  foo print classes     This is probably something really obvious  but I haven t been able to find anything  Can anyone help me out

User · Answer

I frequently find myself writing command line utilities wherein the first argument is meant to refer to one of many different classes. For example ./something.py feature command —-arguments, where Feature is a class and command is a method on that class. Here's a base class that makes this easy.

The assumption is that this base class resides in a directory alongside all of its subclasses. You can then call ArgBaseClass(foo = bar).load_subclasses() which will return a dictionary. For example, if the directory looks like this:

arg_base_class.py
feature.py

Assuming feature.py implements class Feature(ArgBaseClass), then the above invocation of load_subclasses will return { 'feature' : <Feature object> }. The same kwargs (foo = bar) will be passed into the Feature class.

#!/usr/bin/env python3
import os, pkgutil, importlib, inspect

class ArgBaseClass():
    # Assign all keyword arguments as properties on self, and keep the kwargs for later.
    def __init__(self, **kwargs):
        self._kwargs = kwargs
        for (k, v) in kwargs.items():
            setattr(self, k, v)
        ms = inspect.getmembers(self, predicate=inspect.ismethod)
        self.methods = dict([(n, m) for (n, m) in ms if not n.startswith('_')])

    # Add the names of the methods to a parser object.
    def _parse_arguments(self, parser):
        parser.add_argument('method', choices=list(self.methods))
        return parser

    # Instantiate one of each of the subclasses of this class.
    def load_subclasses(self):
        module_dir = os.path.dirname(__file__)
        module_name = os.path.basename(os.path.normpath(module_dir))
        parent_class = self.__class__
        modules = {}
        # Load all the modules it the package:
        for (module_loader, name, ispkg) in pkgutil.iter_modules([module_dir]):
            modules[name] = importlib.import_module('.' + name, module_name)

        # Instantiate one of each class, passing the keyword arguments.
        ret = {}
        for cls in parent_class.__subclasses__():
            path = cls.__module__.split('.')
            ret[path[-1]] = cls(**self._kwargs)
        return ret

User · Answer

What about  g   globals   copy   for name  obj in g iteritems

User · Answer

Go to Python Interpreter  type help   module name     then press Enter  e g  help  os     Here  I ve pasted one part of the output below  class statvfs result   builtin   object          statvfs result  Result from statvfs or fstatvfs                 This object may be accessed either as a tuple of            bsize  frsize  blocks  bfree  bavail  files  ffree  favail  flag  namemax           or via the attributes f bsize  f frsize  f blocks  f bfree  and so on                 See os statvfs for more information                 Methods defined here                   add                    x   add   y   lt    gt  x y                  contains                    x   contains   y   lt    gt  y in x

User · Answer

I was able to get all I needed from the dir built in plus getattr     Works on pretty much everything  but be mindful that    you get lists of strings back  print dir myproject  print dir myproject mymodule  print dir myproject mymodule myfile  print dir myproject mymodule myfile myclass     But  the string names can be resolved with getattr   as seen below    Though  it does come out looking like a hairball   def list supported platforms                    List supported platforms  to match sys platform            Retirms              list str  platform names             return list itertools chain           list                Get the class s constant             getattr                    Get the module s first class  which we wrote                 getattr                        Get the module                     getattr platforms  item                       dir                          getattr platforms  item                        0                                      SYS PLATFORMS                              For each include in platforms   init   py              for item in dir platforms                Ignore magic  ourselves  index py  and a base class              if not item startswith       and item not in   index    base

User · Answer

I don t know if there s a  proper  way to do it  but your snippet is on the right track  just add import foo to foo py  do inspect getmembers foo   and it should work fine

User · Answer

If you want to have all the classes  that belong to the current module  you could use this    import sys  inspect def print classes        is class member   lambda member  inspect isclass member  and member   module        name       clsmembers   inspect getmembers sys modules   name     is class member    If you use Nadia s answer and you were importing other classes on your module  that classes will be being imported too   So that s why member   module        name   is being added to the predicate used on is class member  This statement checks that the class really belongs to the module   A predicate is a function  callable   that returns a boolean value

User · Answer

import Foo  dir Foo   import collections dir collections

User · Answer

Try this   import sys current module   sys modules   name      In your context   import sys  inspect def print classes        for name  obj in inspect getmembers sys modules   name              if inspect isclass obj               print obj    And even better   clsmembers   inspect getmembers sys modules   name     inspect isclass    Because inspect getmembers   takes a predicate

User · Answer

import pyclbr print pyclbr readmodule   name    keys      Note that the stdlib s Python class browser module uses static source analysis  so it only works for modules that are backed by a real  py file

User · Answer

Another solution which works in Python 2 and 3    foo py import sys  class Foo object       pass  def print classes        current module   sys modules   name        for key in dir current module           if isinstance  getattr current module  key   type                print key     test py import foo foo print classes

User · Answer

I think that you can do something like this   class custom object         custom     True class Alpha custom       something   3 def GetClasses        return  x for x in globals   if hasattr globals   str x       custom      print GetClasses       if you need own classes

User · Answer

This is the line that I use to get all of the classes that have been defined in the current module  ie not imported   It s a little long according to PEP-8 but you can change it as you see fit   import sys import inspect  classes    name for name  obj in inspect getmembers sys modules   name     inspect isclass             if obj   module   is   name      This gives you a list of the class names  If you want the class objects themselves just keep obj instead   classes    obj for name  obj in inspect getmembers sys modules   name     inspect isclass            if obj   module   is   name      This is has been more useful in my experience

[python] How can I get a list of all classes within current module in Python?

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