Finding Modules in a Directory

Is there a better way than just listing the contents of the directory, and taking those tiles that end with ".pyc" or ".py"..?

But perhaps there isn't.

   1 import os
   2 import sets
   3 
   4 def find_modules(path="."):
   5     """Return names of modules in a directory.
   6 
   7     Returns module names in a list. Filenames that end in ".py" or
   8     ".pyc" are considered to be modules. The extension is not included
   9     in the returned list.
  10     """
  11     modules = sets.Set()
  12     for filename in os.listdir(path):
  13         module = None
  14         if filename.endswith(".py"):
  15             module = filename[:-3]
  16         elif filename.endswith(".pyc"):
  17             module = filename[:-4]
  18         if module is not None:
  19             s.add(module)
  20     return list(modules)

Importing the Modules

How do you import a module, once you have it's name?

With the ImpModule! It dynamically loads named modules.

   1 import imp
   2 
   3 def load_module(name, path=["."]):
   4     """Return a named module found in a given path."""
   5     (file, pathname, description) = imp.find_module(name, path)
   6     return imp.load_module(name, file, pathname, description)
   7 
   8 modules = [load_module(name) for name in find_modules()]

Finding the Things Inside a Module

Once you have your module, you can look inside it, with .__dict__.

   1 module.__dict__

Finding Functions Within a Module

We just look for dictionary values that are of type types.FunctionType.

   1 def functions_in_module(module)
   2     functions = []
   3     for obj in module.__dict__.values():
   4         if isinstance(obj, types.FunctionType):
   5             functions.append(obj)
   6     return functions

Discussion

(none yet!)

Page

User

Finding Modules in a Directory

Importing the Modules

Finding the Things Inside a Module

Finding Functions Within a Module

See Also

Discussion

-  ⇤ ← Revision 2 as of 2005-04-14 23:11:51 → 
  Size: 1213
  Editor: 168-103-146-113
  Comment:
+   ← Revision 6 as of 2005-10-31 00:45:57 → ⇥
  Size: 2028
  Editor: 68-189-248-26
  Comment: Fixed non-WikiWords.
-Deletions are marked like this.
+Additions are marked like this.
 Line 1:
-I frequently want to find all the modules in some directory, with some property, and do something with them.
+Here's how to find all the modules in some directory, and import them.
 Line 3:
-If you know how, please inform me. Here are some things I'm researching.
+[[TableOfContents()]]

== Finding Modules in a Directory ==

Is there a better way than just listing the contents of the directory, and taking those tiles that end with ".pyc" or ".py"..?

But perhaps there isn't.

{{{
#!python
import os
import sets

def find_modules(path="."):
    """Return names of modules in a directory.

    Returns module names in a list. Filenames that end in ".py" or
    ".pyc" are considered to be modules. The extension is not included
    in the returned list.
    """
    modules = sets.Set()
    for filename in os.listdir(path):
        module = None
        if filename.endswith(".py"):
            module = filename[:-3]
        elif filename.endswith(".pyc"):
            module = filename[:-4]
        if module is not None:
            s.add(module)
    return list(modules)
}}}

== Importing the Modules ==

How do you import a module, once you have it's name?

With the ImpModule! It dynamically loads named modules.

{{{
#!python
import imp

def load_module(name, path=["."]):
    """Return a named module found in a given path."""
    (file, pathname, description) = imp.find_module(name, path)
    return imp.load_module(name, file, pathname, description)

modules = [load_module(name) for name in find_modules()]
}}}
-Line 6:
+Line 54:
+Once you have your module, you can look inside it, with {{{.__dict__}}}.
-Line 12:
+Line 62:
-== Identifying Functions ==

{{{
#!python
import types

def is_it_a_function(obj):
    return isinstance(obj, types.FunctionType)
}}}
-Line 24:
+Line 64:
-So, putting them together,...
+We just look for dictionary values that are of type {{{types.FunctionType}}}.
-Line 36:
+Line 76:
-== Finding Modules in a Directory ==
+== See Also ==
-Line 38:
+Line 78:
-Is there a better way than just listing the contents of the directory, and taking those tiles that end with ".pyc" or ".py"..?
+The DocXmlRpcServer page includes code demonstrating the use of these techniques.
-Line 40:
+Line 80:
-== Importing the Modules ==
+= Discussion =
-Line 42:
+Line 82:
-How do you do it dynamically, just given a filename?

Once you've imported it, how do you get a handle on it? (That is, how do you get it's __dict__?)

There seems to be [http://www.python.org/doc/current/lib/module-imp.html a module imp] that can be used to dynamically load a named module.
+  (none yet!)