Util Python¶

Python specific helper functions

dffml.util.python.modules(root: Union[str, Path], package_name: str, *, skip: Optional[Callable[[str, Path], bool]] = None) → Iterator[Tuple[str, module]][source]¶

Import all modules (Python files) starting at the directory given by root of the package package_name.

Parameters:

• root (str, pathlib.Path) – The path to the directory containing the top level __init__.py of the package.

• package_name (str) – Top level package name of the package your importing. There are no . characters in this. For example, dffml, or dffml_config_yaml.

• skip (callable, optional) – Function that will be called with (import_name, path) and should return a boolean, True if the module should not be imported and yielded to the caller. If it returns False, the Python file at path within package_name will be imported by passing import_name to :py:func`importlib.import_module`.

Yields:

• import_name (str) – The package_name.subdir.file_stem used to import the module.

• module (types.ModuleType) – The imported module.

Examples

You can get all the Python files imported individually in a package as follows.

>>> import dffml
>>> import pathlib
>>> import importlib
>>>
>>> package_name = "xml"
>>> top_level_module = importlib.import_module(package_name)
>>>
>>> root = pathlib.Path(top_level_module.__path__[0])
>>>
>>> # Skip any files in dom/ subdirectory and __main__.py and __init__.py
>>> def skip(_import_name, path) -> bool:
...     return (root / "dom") in path.parents or path.name.startswith("__")
...
>>> # Print the first module
>>> for import_name, module in dffml.modules(root, package_name, skip=skip):
...     print(import_name)
...     break
...
xml.etree.ElementInclude

dffml.util.python.within_method(obj: object, method_name: str, max_depth: int = - 1) → bool[source]¶

Return True if a caller is being called from a given method of a given object.

Parameters:

• obj (object) – Check if we are within a method of this object.

• method_name (str) – Check if we are within a method by this name.

• max_depth (int, optional (-1)) – Stop checking stack frames after we have checked this many.

Returns:

within – True if the calling function is being called from within the method given bound to the object given.

Return type:

boolean

Examples

>>> from dffml import within_method
>>>
>>> class FirstClass:
...     def feedface(self):
...         print(within_method(self, "__init__", max_depth=3))
...
>>> first = FirstClass()
>>> first .feedface()
False
>>>
>>> class SecondClass(FirstClass):
...     def __init__(self):
...         self.feedface()
...
>>> second = SecondClass()
True
>>>
>>> class ThirdClass(SecondClass):
...     def __init__(self):
...         self.deadbeef()
...
...     def deadbeef(self):
...         self.feedface()
...
>>> third = ThirdClass()
False