Function get_callable

django/urls/utils.py:9–56

Return a callable corresponding to lookup_view. * If lookup_view is already a callable, return it. * If lookup_view is a string import path that can be resolved to a callable, import that callable and return it, otherwise raise an exception (ImportError or ViewDoesNotExist).

(lookup_view)

@functools.cache
def get_callable(lookup_view):
    """
    Return a callable corresponding to lookup_view.
    * If lookup_view is already a callable, return it.
    * If lookup_view is a string import path that can be resolved to a
      callable, import that callable and return it, otherwise raise an
      exception (ImportError or ViewDoesNotExist).
    """
    if callable(lookup_view):
        return lookup_view

    if not isinstance(lookup_view, str):
        raise ViewDoesNotExist(
            "'%s' is not a callable or a dot-notation path" % lookup_view
        )

    mod_name, func_name = get_mod_func(lookup_view)
    if not func_name:  # No '.' in lookup_view
        raise ImportError(
            "Could not import '%s'. The path must be fully qualified." % lookup_view
        )

    try:
        mod = import_module(mod_name)
    except ImportError:
        parentmod, submod = get_mod_func(mod_name)
        if submod and not module_has_submodule(import_module(parentmod), submod):
            raise ViewDoesNotExist(
                "Could not import '%s'. Parent module %s does not exist."
                % (lookup_view, mod_name)
            )
        else:
            raise
    else:
        try:
            view_func = getattr(mod, func_name)
        except AttributeError:
            raise ViewDoesNotExist(
                "Could not import '%s'. View does not exist in module %s."
                % (lookup_view, mod_name)
            )
        else:
            if not callable(view_func):
                raise ViewDoesNotExist(
                    "Could not import '%s.%s'. View is not callable."
                    % (mod_name, func_name)
                )
            return view_func


def get_mod_func(callback):