:param salt: salt to hash generate KEY

    :rtype: str

    :returns: sha1 hash from username+salt

    """

    from tempfile import _RandomNameSequence

    import hashlib

    if salt is None:

        salt = _RandomNameSequence().next()

    return hashlib.sha1(username + salt).hexdigest()

def safe_int(val, default=None):

    """

    Returns int() of val if val is not convertable to int use default

    instead

    :param val:

    :param default:

    """

    try:

        val = int(val)

        val = default

    return val

def safe_unicode(str_, from_encoding=None):

    """

    safe unicode function. Does few trick to turn str_ into unicode

    In case of UnicodeDecode error we try to return it with encoding detected

    by chardet library if it fails fallback to unicode with errors replaced

    :param str_: string to decode

    :rtype: unicode

    :returns: unicode object

    """

    if isinstance(str_, unicode):

        return str_

    if not from_encoding:

        import rhodecode

        DEFAULT_ENCODINGS = aslist(rhodecode.CONFIG.get('default_encoding',

                                                        'utf8'), sep=',')

        from_encoding = DEFAULT_ENCODINGS