merge.py

#!/usr/bin/env python
import csv
import datetime
import json
import re
import sys

from decimal import Decimal as D
from collections import defaultdict


ZERO = D('0.00')
DAY = datetime.timedelta(days=1)

gratipay = json.load(open('gratipay.json'))
liberapay = json.load(open('liberapay.json'))
good_rate = re.compile(r'\d+\.\d+')
euro = {date: D(rate) for date, rate in csv.reader(open('DEXUSEU.csv')) if good_rate.match(rate)}
merged = defaultdict(dict)
Datetime = lambda date: datetime.date(*map(int, date.split('-')))
week = lambda date: Datetime(date) - datetime.timedelta(days=Datetime(date).weekday())


def find_rate(date):
    if date in euro:
        return euro[date]
    return find_rate((Datetime(date) + DAY).strftime('%Y-%m-%d'))


for payday in gratipay:
    usd = D(payday['volume'])
    rate = find_rate(payday['date'])
    eur = round(usd / rate, 2)
    merged[week(payday['date'])]['gratipay'] = eur

for payday in liberapay:
    volume = payday.get('volume', payday.get('transfer_volume', {}).get('amount'))
    merged[week(payday['date'])]['liberapay'] = D(volume)

out = csv.writer(sys.stdout)
out.writerow(['week', 'gratipay', 'liberapay'])
for date, vals in sorted(merged.items()):
    gratipay = vals.get('gratipay', 0)
    liberapay = vals.get('liberapay', 0)
    out.writerow([date, gratipay, liberapay])