currency.py

import requests
from templates.text import TextTemplate
from error_msg import CONVERT_ERROR, EXAMPLE_CONVERSIONS

def process(input, entities):
    output = {}
    try:
        from_currency = entities['from_currency'][0]['value'].upper()
        to_currency = entities['to_currency'][0]['value'].upper()
        r = requests.get('http://api.fixer.io/latest?base=' + from_currency)
        data = r.json()
        conversion_rate = data['rates'][to_currency]

        conversion_details = '1 %s = %.4f %s' % (from_currency, conversion_rate, to_currency)
        if 'number' in entities:
            amount = entities['number'][0]['value']
            if amount != 1:
                conversion_details += '\n%s %s = %.4f %s' % (amount, from_currency, amount * conversion_rate, to_currency)

        output['input'] = input
        output['output'] = TextTemplate(conversion_details).get_message()
        output['success'] = True
    except:
        error_message = CONVERT_ERROR.format('currencies') + EXAMPLE_CONVERSIONS
        output['error_msg'] = TextTemplate(error_message).get_message()
        output['success'] = False
    return output