std_of_time_series

import statistics

from influxdb_client_3 import SYNCHRONOUS, Point
from influxdb_client_3.write_client.client import influxdb_client


def calculate_std(time_series):
    if len(time_series) < 2:
        return None
    std_deviation = statistics.stdev(time_series)
    return std_deviation


def std_deviation_to_influxdb(time_serie_data, url, token, org, bucket_name):
    """ Function to calculate standard deviation from time series and store it in influxdb

    :param time_serie_data: given time series data
    :param url: url of influxdb server
    :param token: token of influxdb client
    :param org: name of influxdb organization
    :param bucket_name: bucket where data will be stored
    :return: None
    """
    write_client = influxdb_client.InfluxDBClient(
        url=url,
        token=token,
        org=org
    )

    # calculate std and create data point
    measurement_name = 'std_of_time_series'
    field_name = 'std_deviation'
    std_deviation = calculate_std(time_serie_data)
    std_deviation_point = (
        Point(measurement_name)
        .field(field_name, std_deviation)
    )

    # store data point to corresponding bucket
    write_api = write_client.write_api(write_options=SYNCHRONOUS)
    write_api.write(bucket=bucket_name,
                    org=org,
                    record=std_deviation_point)