Namespace¶

Merging two Python packages into one namespace¶

Option 1: pkgutil (legal)

• Use a special __init__.py file at the root of the namespace package that explicitly tells Python to extend its path

• from pkgutil import extend_path;__path__ = extend_path(__path__, __name__) or

• __path__ = __import__('pkgutil').extend_path(__path__, __name__)

Option 2: no __init__.py

• omit the __init__.py file in the top-level directory of the shared namespace

• packaging with setuptools, have to use find_namespace_packages

  # In setup.py or pyproject.toml
  from setuptools import setup, find_namespace_packages
  setup(
      name='my_company-core',
      ...
      packages=find_namespace_packages(where='src'),
      package_dir={'': 'src'},
  )
  

inspect namespaces in a package¶

• use dir to list all objects

• use inspect to check object types

  import inspect
  import polars as pl
  
  def list_polars_namespaces_to_file(module, file_object, indent=0, max_level=5):
      """
      Recursively lists all "namespaces" (sub-modules and significant objects)
      within a given module, writing to a file with a maximum level depth.
      """
      if indent >= max_level:
          return
      prefix = "  " * indent
      for name in sorted(dir(module)):
          if name.startswith("_"):  # Skip private/internal attributes
              continue
          obj = getattr(module, name)
          if inspect.ismodule(obj) and obj.__name__.startswith('polars.'):
              # If it's a sub-module within polars
              file_object.write(f"{prefix}{name}\n")
              list_polars_namespaces_to_file(obj, file_object, indent + 1, max_level)
          elif inspect.isclass(obj) or inspect.isfunction(obj) or isinstance(obj, (int, float, str, bool, list, dict, set)) or (
              hasattr(obj, '__module__') and obj.__module__ and obj.__module__.startswith('polars.')
          ):
              # Consider classes, functions, common data types, and other polars-related objects
              file_object.write(f"{prefix}{name}\n")
  
  max_depth = 5
  output_filename = "./polars_namespaces.txt"
  with open(output_filename, "w") as f:
      f.write("polars\n")
      list_polars_namespaces_to_file(pl, f, indent=1, max_level=max)