utils_misc.py

import time
import random
import string
import re

def wait_for_output(func, timeout, first=0.0, step=1.0):
    end_time = time.time() + float(timeout)
    time.sleep(first)

    while time.time() < end_time:
        output = func()
        if output:
            return output
        time.sleep(step)

    return None

def wait_for_keyword(func, keyword, timeout, first=0.0, step=1.0):
    end_time = time.time() + float(timeout)
    time.sleep(first)
    while time.time() < end_time:
        output = func()
        if re.search(keyword, output):
            return output
        time.sleep(step)
    return None

def py3_to_str(bytes_or_str):
    if isinstance(bytes_or_str, bytes):
        value = bytes_or_str.decode('utf-8')
    else:
        value = bytes_or_str
    return value

def py3_to_bytes(bytes_or_str):
    if isinstance(bytes_or_str, str):
        value = bytes_or_str.encode('utf-8')
    else:
        value = bytes_or_str
    return value

def py2_to_unicode(unicode_or_str):
    if isinstance(unicode_or_str, str):
        value = unicode(unicode_or_str, 'utf-8')
    else:
        value = unicode_or_str
    return value

def py2_to_srt(unicode_or_str):
    if isinstance(unicode_or_str, unicode):
        value = unicode_or_str.encode('utf-8')
    else:
        value = unicode_or_str
    return value

def generate_random_string(length, ignore_str=string.punctuation,
                           convert_str=""):
    """
    Return a random string using alphanumeric characters.
    :param length: Length of the string that will be generated.
    :param ignore_str: Characters that will not include in generated string.
    :param convert_str: Characters that need to be escaped (prepend "\\").
    :return: The generated random string.
    """
    r = random.SystemRandom()
    sr = ""
    chars = string.ascii_letters + string.digits + string.punctuation
    if not ignore_str:
        ignore_str = ""
    for i in ignore_str:
        chars = chars.replace(i, "")

    while length > 0:
        tmp = r.choice(chars)
        if convert_str and (tmp in convert_str):
            tmp = "\\%s" % tmp
        sr += tmp
        length -= 1
    return sr