Update Splitwise group expenses

UpdateExpenses.py

# This script wasn't completed. There is an authentication error returned when we attempt to update
# a transaction. The strange thing is that we are allowed to retrieve items with no problems,
# also if we send an invalid write, we receive an error response which makes sense (i.e. when 
# Sum(user_costs) != expense_cost
#
# If we were finishing this script we would need to do the following: 
# 1) Use a proper exchange rate 
# 2) Detect when currency == JPY, only covert then 
# 3) Update the currency value to AUD after the conversion 
# 4) Some kind of logging in case we mess things up

from requests_oauthlib import OAuth1Session
import requests
from requests_oauthlib import OAuth1

consumer_key = "<snip>"
consumer_secret = "<snip>"

request_token_url = "https://secure.splitwise.com/oauth/request_token"
access_token_url = "https://secure.splitwise.com/oauth/access_token"
autorize_url = "https://secure.splitwise.com/oauth/authorize"


def use_keys():
    print("using keys")
    resource_owner_key = "<snip>"
    resource_owner_secret = "<snip>"

    oauth = OAuth1Session(consumer_key,
                          client_secret=consumer_secret,
                          resource_owner_key=resource_owner_key,
                          resource_owner_secret=resource_owner_secret,
                          signature_type='auth_header')

    r = oauth.get('https://secure.splitwise.com/api/v3.0/test')
    print(r)
    print(r.json())
    return oauth

def get_keys():

    # Get Access Token

    oauth = OAuth1Session(consumer_key, client_secret=consumer_secret)

    fetch_response = oauth.fetch_request_token(request_token_url)

    print(fetch_response)

    # User Authorisation
    resource_owner_key = fetch_response.get('oauth_token')
    resource_owner_secret = fetch_response.get('oauth_token_secret')

    print ("Resource owner key: {}".format(resource_owner_key))
    print ("Secret: {}".format(resource_owner_secret))


    authorization_url = oauth.authorization_url(autorize_url)
    print 'Please go here and authorize,', authorization_url
    oauth_verifier = raw_input("Paste the oauth_verifier from Splitwise here: ")


    # Get Access Token
    oauth = OAuth1Session(consumer_key,
                              client_secret=consumer_secret,
                              resource_owner_key=resource_owner_key,
                              resource_owner_secret=resource_owner_secret,
                              verifier=oauth_verifier)
    oauth_tokens = oauth.fetch_access_token(access_token_url)
    print("oauth_tokens: {}".format(oauth_tokens))


    resource_owner_key = oauth_tokens.get('oauth_token')
    resource_owner_secret = oauth_tokens.get('oauth_token_secret')

    print("Save these keys for later:")
    print("resource_owner_key : {}".format(resource_owner_key))
    print("resource_owner_secret : {}".format(resource_owner_secret))

    r = oauth.get('https://secure.splitwise.com/api/v3.0/test')
    print(r)
    print(r.json())

    return oauth

def find_group_with_name(oauth, name):
    r = oauth.get('https://secure.splitwise.com/api/v3.0/get_groups')
    json_response = r.json()
    groups =  json_response['groups']

    for item in groups:
        print(item['name'])
        if item['name'] == name:
            print("Found Match")
            return item

    print("Error: No group found with name: {}".format(name))
    return ""

def update_expense(oauth, expense):
    print(expense)
    print("Cost: " + expense['cost'])
    print("Name: " + expense['description'])
    users = expense['users']

    expense_multiplier = 2.0

    updated_users = []
    # Update contributions for each user
    for user in users:
        paid_share = float(user['paid_share'])
        owed_share = float(user['owed_share'])
        new_paid_share = paid_share * expense_multiplier
        new_owed_share = owed_share * expense_multiplier
        print ("User ID: {} Paid: {} Owed: {} Net Balance: {}".format(user['user_id'],user['paid_share'],user['owed_share'],user['net_balance']))
        new_user = {'user_id':user['user_id'], 'paid_share':new_paid_share,'owed_share':new_owed_share}
        updated_users.append(new_user)

    url = "https://secure.splitwise.com/api/v3.0/update_expense/{}".format(expense['id'])
    print("Posting to {}".format(url))

    # Multipy overall cost
    cost = float(expense['cost'])
    new_cost = expense_multiplier * cost
    data = {'cost' : new_cost, 'users' : updated_users}

    print("\nNew Data: {}".format(data))

    response = oauth.post(url,data)
    print(response)
    print(response.json())

def get_expenses_for_group(oauth,group_id):
    print("Get Expenses for Group: {}".format(group_id))
    url = 'https://secure.splitwise.com/api/v3.0/get_expenses?group_id={}&limit=0'.format(group_id)
    r = oauth.get(url)
    expenses = r.json()['expenses']
    print ("Group contains {} expenses".format(len(expenses)))

    expense = expenses[0]
    update_expense(oauth, expense)

def main():
    print("Get Keys")
    #oauth = get_keys()
    oauth = use_keys()
    group_name = "Niseko 2016"
    group = find_group_with_name(oauth,group_name)
    print(group)

    get_expenses_for_group(oauth,group['id'])

if __name__ == "__main__":
    main()