weathericon.py

#!/usr/bin/env python

import datetime
import json
from urllib import request
from bottle import route, run, debug, static_file

SETTINGS_FILE_PATH = 'wi_settings.json'
THRESHOLDS_FILE_PATH = 'radiation_threshold_images.json'
ERROR_IMAGE_FILE_PATH = 'img/error.png'

KEY_HOST = 'host'
KEY_PORT = 'port'
KEY_DATA_SOURCE = 'dataSource'
KEY_AVERAGE_SAMPLES = 'averageSamples'

DATA_VALUE_SEPARATOR = ','
DATA_INDEX_MEASURED_RADIATION = 18
DATA_INDEX_MAX_RADIATION = 22


@route('/current')
def current_reading():
	single_value = calculate_average_over_n(1)
	print("Current ratio value: {}".format(single_value))
	return static_file(filename=get_image_for_ratio(single_value), root='.')


@route('/average')
def average_reading():
	average_value = calculate_average_over_n(int(get_settings()[KEY_AVERAGE_SAMPLES]))
	print("Average ratio value: {}".format(average_value))
	return static_file(filename=get_image_for_ratio(average_value), root='.')


def calculate_average_over_n(n):
	data_lines = get_data()
	if len(data_lines) < n:
		n = len(data_lines)
	if n > 0:
		try:
			ratio_sum = 0.0
			for line in data_lines[-n:]:
				ratio_sum += calculate_ratio_from_line(line)
			return ratio_sum/n
		except IOError:
			return -1.0
	else:
		return -1.0


def calculate_ratio_from_line(line):
	values = line.split(DATA_VALUE_SEPARATOR)
	measurement = float(values[DATA_INDEX_MEASURED_RADIATION])
	maximum = float(values[DATA_INDEX_MAX_RADIATION])
	if maximum == 0:
		return 0.0
	return measurement/maximum


def get_image_for_ratio(ratio):
	radiation_threshold_images = get_radiation_threshold_images()
	img_path = radiation_threshold_images[-1][1]
	for rt in radiation_threshold_images:
		if ratio <= rt[0]:
			img_path = rt[1]
	return img_path


def get_data():
	with request.urlopen(get_data_source()) as data:
		return [str(data_line) for data_line in data.readlines()]


def get_data_source():
	ds_template = get_settings()[KEY_DATA_SOURCE]
	current_date = datetime.datetime.now()
	return current_date.strftime(ds_template)


def get_settings():
	with open(SETTINGS_FILE_PATH) as settings_file:
		return json.load(settings_file)


def get_radiation_threshold_images():
	with open(THRESHOLDS_FILE_PATH) as thresholds_file:
		threshold_ratio_images = json.load(thresholds_file)
		radiation_threshold_images = [(float(tr), threshold_ratio_images[tr]) for tr in threshold_ratio_images]
		radiation_threshold_images.append((-1.0, ERROR_IMAGE_FILE_PATH))
		radiation_threshold_images.sort(reverse=True)
		return radiation_threshold_images


debug(True)
run(host=get_settings()[KEY_HOST], port=get_settings()[KEY_PORT])