weather_observed.py

#!bin/python
# -*- coding: utf-8 -*-

from __future__ import print_function
from flask import Flask, jsonify, request, Response
import urllib2
import StringIO
import csv
import datetime
import json

weather_observed = ("http://www.aemet.es/es/eltiempo/observacion/ultimosdatos_{}_datos-horarios.csv"
                    "?k=cle&l={}&datos=det&w=0&f=temperatura&x=h6")


def get_data(row, index, conversion=float, factor=1.0):
    value = row[index]
    return None if value == '' else conversion(value) / factor


def get_weather_observed(request):
    query = request.args.get('q')

    if not query:
        return Response(json.dumps([]), mimetype='application/json')

    tokens = query.split(';')

    station_code = ''
    country = ''

    for token in tokens:
        items = token.split(':')
        if items[0] == 'stationCode':
            station_code = items[1]
        elif items[0] == 'country':
            country = items[1]

    if not station_code or not country or country != 'ES':
        return Response(json.dumps([]), mimetype='application/json')

    source = weather_observed.format(station_code, station_code)

    req = urllib2.Request(url=source)
    f = urllib2.urlopen(req)
    csv_data = f.read()

    csv_file = StringIO.StringIO(csv_data)
    reader = csv.reader(csv_file, delimiter=',')

    out = []
    index = 0
    for row in reader:
        if index == 0:
            address = row[0]

        if index < 4:
            index += 1
            continue

        print(row)

        observation = {
            'type': 'WeatherObserved'
        }
        if len(row) < 2:
            continue

        observation['temperature'] = get_data(row, 1)
        observation['windSpeed'] = get_data(row, 2, int)
        observation['windDirection'] = row[3] or None
        observation['precipitation'] = get_data(row, 6)
        observation['pressure'] = get_data(row, 7)
        observation['pressureTendency'] = get_data(row, 8)
        observation['relativeHumidity'] = get_data(row, 9, factor=100.0)

        observation['dateObserved'] = datetime.datetime.strptime(
            row[0], '%d/%m/%Y %H:%M').isoformat()
        observation['source'] = 'http://www.aemet.es'
        observation['address'] = {
            'addressLocality': address.decode('latin-1'),
            'addressCountry': country
        }

        out.append(observation)

    print(out)
    return Response(json.dumps(out), mimetype='application/json')