# The MIT License (MIT) # Copyright (c) 2014-2017 University of Bristol
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
# DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
# OR OTHER DEALINGS IN THE SOFTWARE.
import json
import pytz
from datetime import datetime, date, timedelta
import os
if os.name != 'nt':
import udatetime
else:
udatetime = datetime
# noinspection PyClassHasNoInit
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 remove_microseconds(ts):
milliseconds = int(ts.microsecond / 1000 * 1000)
return datetime(ts.year, ts.month, ts.day, ts.hour, ts.minute, ts.second, milliseconds, UTC)
[docs]def utcnow():
"""
Gets the current datetime in UTC format with millisecond precision
:return:
"""
now = udatetime.utcnow().replace(tzinfo=UTC)
return remove_microseconds(now)
[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 datetime2unix(dt):
return (dt - datetime(1970, 1, 1, tzinfo=UTC)).total_seconds()
[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)
[docs]def is_naive(dt):
return dt.tzinfo is None or dt.tzinfo.utcoffset(dt) is None
[docs]def json_serial(obj):
"""JSON serializer for objects not serializable by default json code"""
if isinstance(obj, (datetime, date)):
serial = obj.isoformat()
return serial
from ..time_interval import TimeInterval, TimeIntervals
if isinstance(obj, (TimeInterval, TimeIntervals)):
return obj.to_json()
from ..stream import StreamId
if isinstance(obj, StreamId):
return obj.to_json()
from ..channels import BaseChannel
if isinstance(obj, BaseChannel):
return json.dumps({'channel_id': obj.channel_id})
raise TypeError("Type %s not serializable" % type(obj))