Source code for hyperstream.utils.time_utils

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import pytz
from datetime import datetime, timedelta
import udatetime


class UTC(pytz.UTC):
    def __repr__(self):
        return "UTC"


MIN_DATE = datetime.min.replace(tzinfo=UTC)
MAX_DATE = datetime.max.replace(tzinfo=UTC).replace(microsecond=0)


[docs]def utcnow():
    """
    Gets the current datetime in UTC format with millisecond precision
    :return:
    """
    now = udatetime.utcnow().replace(tzinfo=UTC)
    return datetime(now.year, now.month, now.day, now.hour, now.minute, now.second, now.microsecond / 1000 * 1000, UTC)


[docs]def get_timedelta(value):
    if isinstance(value, (int, float)):
        return timedelta(seconds=value)
    elif isinstance(value, timedelta):
        return value
    else:
        raise ValueError("Expected int, float, or timedelta, got {}".format(type(value)))


[docs]def unix2datetime(u):
    return udatetime.fromtimestamp(u / 1000.0, tz=UTC) + timedelta(hours=0)


[docs]def duration2str(x):
    minutes, seconds = divmod(x.total_seconds(), 60)
    return '{} min {} sec'.format(int(minutes), int(seconds))


[docs]def construct_experiment_id(time_interval):
    """
    Construct an experiment id from a time interval
    :return: The experiment id
    :type time_interval: TimeInterval
    :rtype: str
    """
    # Construct id based on unix epoch timestamps
    epoch = udatetime.utcfromtimestamp(0).replace(tzinfo=UTC)
    start = int((time_interval.start - epoch).total_seconds() * 1000.0)
    end = int((time_interval.end - epoch).total_seconds() * 1000.0)
    return "{}-{}".format(start, end)


[docs]def reconstruct_interval(experiment_id):
    """
    Reverse the construct_experiment_id operation
    :param experiment_id: The experiment id
    :return: time interval
    """
    start, end = map(lambda x: udatetime.utcfromtimestamp(x / 1000.0), map(float, experiment_id.split("-")))
    from ..time_interval import TimeInterval
    return TimeInterval(start, end)