common_radiohdl.py

import os
import inspect


def listify(obj):
    """
    Can be used to force method input to a list.
    """
    if isinstance(obj, list):
        return obj
    else:
        return [obj]

    # try:
    #     return list(obj)
    # except TypeError:
    #     return [obj]


def unlistify(obj):
    """
    Converts 1-element list to x.
    """
    # The isinstance() built-in function is recommended over the type()
    # built-in function for testing the type of an object
    if isinstance(obj, list):
        if len(obj) == 1:
            return obj[0]
    return obj


def remove_from_list_string(list_str, item_str, sep=' '):
    """Treat the string list_str as a list of items that are separated by sep and then
       remove the specified item_str string from the list and return the list as a
       string of items separated by sep. Also remove any duplicate items.
    """
    _list_str = list_str.split(sep)
    _list_str = unique(_list_str)
    _list_str.remove(item_str)
    return sep.join(_list_str)


def unique(in_list):
    """
    Extract unique list elements (without changing the order like set() does)
    """
    result = []
    for item in in_list:
        if item in result:
            continue
        result.append(item)
    return result


def method_name(caller_depth=0):
    """
    Returns the name of the caller method.
    """
    # Note: inspect.stack()[0][3] would return the name of this method.
    return inspect.stack()[caller_depth+1][3]


def mkdir(path):
    """Recursively create leave directory and intermediate directories if they do not already exist."""
    expand_path = os.path.expandvars(path)        # support using environment variables in the file path
    expand_path = os.path.expanduser(expand_path)  # support using ~ in the file path
    if not os.path.exists(expand_path):
        os.makedirs(expand_path)


def expand_file_path_name(fpn, dir_path=''):
    """ Expand environment variables in fpn to get file_path_name.
    - if it is an absolute path return file_path_name else
    - if it still has a local file path prepend dir_path to the file_path_name and return dir_path + file_path_name.
    """
    file_path_name = os.path.expandvars(fpn)           # support using environment variables in the file path
    file_path_name = os.path.expanduser(file_path_name)  # support using ~ in the file path
    if os.path.isabs(file_path_name):
        return file_path_name                          # use absolute path to file

    # derive path to file from the directory path and a directory path to the file
    return os.path.join(os.path.expandvars(dir_path), file_path_name)