rowsandall/rowers/weather.py

import requests
from requests.exceptions import ConnectionError
import json
from lxml import objectify, etree
import xml.etree.ElementTree as ET
import time
from datetime import datetime
from rowingdata import rowingdata, geo_distance
import arrow
import pandas as pd
from rowers.models import Rower, Workout

from rowsandall_app.settings import FORECAST_IO_KEY

# Find closest airport


def get_airport_code(lat, lon):
    metardata = pd.read_csv('rowers/data/metarlatlon.csv')
    deltasq = (lat-metardata.lat)**2+(lon-metardata.lon)**2
    a = metardata[deltasq == deltasq.min()]
    airport_code = a.iloc[0]['icao']
    newlat = a.iloc[0]['lat']
    newlon = a.iloc[0]['lon']
    distance = geo_distance(lat, lon, newlat, newlon)
    return airport_code, newlat, newlon, distance

# Get weather data from the DarkSky API


def get_weather_data(long, lat, unixtime):
    url = "https://api.darksky.net/forecast/"+FORECAST_IO_KEY+"/"
    url += str(long)+","+str(lat)+","+str(unixtime)

    try:
        s = requests.get(url)
    except ConnectionError:  # pragma: no cover
        return 0

    if s.ok:
        try:
            return s.json()
        except:
            return 0
    else:  # pragma: no cover
        return 0

# Get Metar data


def get_metar_data(airportcode, unixtime):

    timestamp = arrow.get(unixtime).isoformat()

    url = "https://www.aviationweather.gov/adds/dataserver_current/httpparam?dataSource=metars&requestType=retrieve&format=xml&startTime="
    url += str(unixtime-3600)
    url += "&endTime="
    url += str(unixtime+3600)
    url += "&stationString="+airportcode

    try:
        s = requests.get(url)
    except:  # pragma: no cover
        message = 'Failed to download METAR data'
        return [0, 0, message, '', '']

    if s.ok:  # pragma: no cover
        try:
            doc = etree.fromstring(s.content)
        except AttributeError:
            message = 'METAR data content error'
            return [0, 0, message, '', 0]
        lengte = len(doc.xpath('data/METAR/station_id'))
        idnr = int(lengte/2)
        try:
            _ = doc.xpath('data/METAR/station_id')[idnr].text
            temp_c = doc.xpath('data/METAR/temp_c')[idnr].text
            wind_dir = doc.xpath('data/METAR/wind_dir_degrees')[idnr].text
            wind_speed = doc.xpath('data/METAR/wind_speed_kt')[idnr].text
            timestamp = doc.xpath('data/METAR/observation_time')[idnr].text
            rawtext = doc.xpath('data/METAR/raw_text')[idnr].text
        except IndexError:
            message = 'Failed to download METAR data'
            return [0, 0, message, '', timestamp]

        windbearing = float(wind_dir)
        wind_knots = float(wind_speed)
        wind_ms = 0.514444*wind_knots
        wind_ms = int(10*wind_ms)/10.

        temperaturec = float(temp_c)
        temp_f = 32.+(9./5.)*temperaturec
        temp_f = str(int(10*temp_f)/10.)

        message = 'Summary for your location at '+timestamp+': '
        message += 'Temperature '+temp_c+'C/'+temp_f+'F'
        message += '. Wind: '+str(wind_ms)+' m/s ('+str(wind_knots)+' kt)'
        message += '. Wind Bearing: '+str(windbearing)+' degrees'
#        message +='\n'+rawtext

        return [wind_ms, windbearing, message, rawtext, timestamp]

    message = 'Failed to download METAR data'  # pragma: no cover
    return [0, 0, message, '', timestamp]  # pragma: no cover


# Get wind data (and translate from knots to m/s)
def get_wind_data(lat, long, unixtime):
    data = get_weather_data(lat, long, unixtime)
    summary = ''
    temperature = 20
    if data:  # pragma: no cover
        try:
            # we are getting wind in mph
            windspeed = data['currently']['windSpeed']*0.44704
            windbearing = data['currently']['windBearing']
        except KeyError:
            windspeed = 0
            windbearing = 0

        try:
            airports = data['flags']['madis-stations']
        except KeyError:
            airports = ['unknown']

        try:
            temperature = data['currently']['temperature']
            # Temp is given in Fahrenheit, so convert to Celsius for Europeans
            temperaturec = (temperature-32.)*(5./9.)
            temperaturec = int(10*temperaturec)/10.
        except KeyError:
            temperature = 'unknown'
            temperaturec = 'unknown'

        try:
            summary = data['currently']['summary']
        except KeyError:
            summary = 'unknown'
    else:
        windspeed = 0
        windbearing = 0
        summary = 'unknown'
        airports = ['unknown']
        temperature = 'unknown'
        temperaturec = 'unknown'
        message = 'Not able to get weather data'

    # apply Hellman's coefficient for neutral air above human
    # inhabitated areas
    windspeed = windspeed*(0.1)**0.34
    windspeed = 0.01*int(100*windspeed)

    timestamp = arrow.get(unixtime).isoformat()

    message = 'Summary for your location at '+timestamp+': '+summary
    message += '. Temperature '+str(temperature)+'F/'+str(temperaturec)+'C'

    if data:  # pragma: no cover
        message += '. Wind: ' + \
            str(windspeed)+' m/s. Wind Bearing: '+str(windbearing)+' degrees'

    return [windspeed, windbearing, message, airports, timestamp]