helm/bin/shekel
2017-06-28 19:33:12 +02:00

131 lines
3.5 KiB
Python
Executable file

#!/usr/bin/env python3
# A shell script that converts one currency to another.
#
# Usage: shekel AMOUNT FROM TO
#
# FROM and TO are either currency codes or a fuzzy substring (requires iterfzf
# and fzf).
#
# Examples:
# shekel 200 USD CAD
# Don't remember the currency code? Use fuzzy search:
# shekel 200 USD british
# This will spawn an fzf session (requires the iterfzf package and fzf)
#
# Requires: iterfzf (optional)
import sys
import os
import json
from urllib import request
from datetime import datetime
from base64 import b64encode
try:
from iterfzf import iterfzf
except:
pass
API_KEY = "92a7ccb3b6038a7151fc15e99f2de83d" # please use your own!
API_URL = "http://apilayer.net/api/live?access_key={}&currencies={},{}"
DB_URL = "https://raw.githubusercontent.com/hlissner/lb6-actions/master/Convert%20Currency.lbaction/Contents/Resources/currencies.json"
DEFAULT_CODE = "CAD"
CACHE_FILE = os.path.expanduser("~/.cache/shekel-hist")
CACHE_TTL = 3600
CACHE = {}
def _request(url, *args):
try:
real_url = url.format(*map(request.quote, map(str, args)))
resp = request.urlopen(real_url).read().decode('utf-8')
data = json.loads(resp)
if data['success']:
return data["quotes"]
raise Exception(data['error']['info'])
except IOError:
print("IOError")
def _cache(key, value):
CACHE[key] = {
'time': datetime.now().timestamp(),
'value': value
}
def cache(from_code, to_code, fn, ttl=CACHE_TTL):
key = "-".join([from_code, to_code])
if key not in CACHE or CACHE[key]['time'] > CACHE[key]['time'] + ttl:
value = fn()
if value is not None:
_cache(key, value)
_cache("-".join([to_code, from_code]), value)
return CACHE[key]['value']
def get_rate(from_code, to_code=DEFAULT_CODE):
if from_code == to_code:
raise ValueError("Trying to convert currency to itself ({})".format(from_code))
elif from_code is None or to_code is None:
return None
rates = cache(
from_code,
to_code,
lambda: _request(API_URL, API_KEY, from_code, to_code)
)
src = rates["USD" + from_code]
dest = rates["USD" + to_code]
return (1 / src) * dest
def parse(codes, db):
for i, code in enumerate(codes):
if len(code) == 3 and code.isupper():
continue
resp = iterfzf(currencies(), query=code)
if resp is None:
codes[i] = None
else:
codes[i] = resp.split(" ")[0]
return codes
def currencies():
for curr in CACHE['_DB']:
yield "{} {}".format(curr['id'], curr['currencyName'])
def usage():
print("Usage: {} AMOUNT FROM [TO]".format(sys.argv[0]))
#
if __name__ == '__main__':
refresh = False
if "-f" in sys.argv:
refresh = True
sys.argv.remove('-f')
if len(sys.argv) < 3:
usage()
sys.exit(1)
if refresh:
CACHE = {}
else:
if os.path.isfile(CACHE_FILE):
with open(CACHE_FILE, 'r') as f:
CACHE = json.load(f)
if "_DB" not in CACHE:
CACHE['_DB'] = json.loads(request.urlopen(DB_URL).read().decode('utf-8'))
amount, codes = float(sys.argv[1]), parse(sys.argv[2:4], CACHE['_DB'])
rate = get_rate(*codes)
if rate is None:
print("Aborted")
else:
converted_amount = amount * rate
print("{:.6f} {}".format(converted_amount, codes[1]))
with open(CACHE_FILE, 'w') as f:
json.dump(CACHE, f)
sys.exit(0)