Implement fetching account balances

handler/sinks/__init__.py

@@ -87,3 +87,16 @@ class Sinks(util.Base):
         # {"EUR": {"IBAN": "xxx", "BIC": "xxx"},
         #  "GBP": {"SORT": "04-04-04", "ACCOUNT": "1922-2993"}}
         # self.markets.distribute_account_details(currencies, account_infos)
+
+    def get_total_usd(self):
+        """
+        Get the total balance of our accounts in USD.
+        """
+        total_nordigen = self.nordigen.get_total_map()
+        total_truelayer = self.truelayer.get_total_map()
+
+        # Yes, we can save an API call by merging but I think this is clearer
+        total_nordigen_usd = self.money.multiple_to_usd(total_nordigen)
+        total_truelayer_usd = self.money.multiple_to_usd(total_truelayer)
+
+        return total_truelayer_usd + total_nordigen_usd

handler/sinks/nordigen.py

@@ -5,7 +5,7 @@ from twisted.internet.task import LoopingCall
 import requests
 from simplejson.errors import JSONDecodeError
 from json import dumps, loads
-from lib.serde.nordigen import TXRoot, AccessToken, Institutions, Agreement, Requisitions, AccountDetails
+from lib.serde.nordigen import TXRoot, AccessToken, Institutions, Agreement, Requisitions, AccountDetails, AccountBalancesRoot
 from serde import ValidationError
 
 # Project imports
@@ -242,9 +242,6 @@ class Nordigen(util.Base):
                 continue
             accounts = self.get_accounts(req["id"])
             for account_id in accounts:
-                # if not account_id in self.banks:
-                #    print("account_id", account_id, "not in self.banks!")
-                #    continue
                 account_info = self.get_account(account_id)
                 if not account_info:
                     continue
@@ -281,7 +278,55 @@ class Nordigen(util.Base):
         headers = {"accept": "application/json", "Authorization": f"Bearer {self.token}"}
         path = f"{settings.Nordigen.Base}/accounts/{account_id}/transactions/"
         r = requests.get(path, headers=headers)
-        obj = TXRoot.from_json(r.content)
+        try:
+            obj = TXRoot.from_json(r.content)
+        except ValidationError as err:
+            self.log.error(f"Validation error: {err}")
+            return
         parsed = obj.to_dict()["transactions"]["booked"]
         self.normalise_transactions(parsed)
         return parsed
+
+    def get_balance(self, account_id):
+        """
+        Get the balance and currency of an account.
+        :param account_id: the account ID
+        :return: tuple of (currency, amount)
+        :rtype: tuple
+        """
+        headers = {"accept": "application/json", "Authorization": f"Bearer {self.token}"}
+        path = f"{settings.Nordigen.Base}/accounts/{account_id}/balances/"
+        r = requests.get(path, headers=headers)
+        try:
+            obj = AccountBalancesRoot.from_json(r.content)
+        except ValidationError as err:
+            self.log.error(f"Validation error: {err}")
+            return
+        parsed = obj.to_dict()["balances"]
+        total = 0
+        currency = None
+        for entry in parsed:
+            if currency:
+                if not currency == entry["balanceAmount"]["currency"]:
+                    self.log.error("Different currencies in balance query.")
+                    return
+            total += float(entry["balanceAmount"]["amount"])
+            currency = entry["balanceAmount"]["currency"]
+        return (currency, total)
+
+    def get_total_map(self):
+        """
+        Return a dictionary keyed by currencies with the amounts as values.
+        :return: dict keyed by currency, values are amounts
+        :rtype: dict
+        """
+        totals = {}
+        for account_id in self.banks:
+            currency, amount = self.get_balance(account_id)
+            if not amount:
+                continue
+            if currency in totals:
+                totals[currency] += amount
+            else:
+                totals[currency] = amount
+        return totals

handler/sinks/truelayer.py

@@ -6,7 +6,9 @@ import requests
 from simplejson.errors import JSONDecodeError
 from time import time
 from json import dumps, loads
+from lib.serde.truelayer import AccountBalancesRoot
 import urllib
+from serde import ValidationError
 
 # Project imports
 from settings import settings
@@ -274,8 +276,55 @@ class TrueLayer(util.Base):
             parsed = r.json()
         except JSONDecodeError:
             self.log.error(f"Error parsing transactions response: {r.content}")
-            return False
+            return (False, False)
         if "results" in parsed:
             return parsed["results"]
         else:
-            return False
+            return (False, False)
+
+    def get_balance(self, bank, account_id):
+        """
+        Get the balance of an account.
+        :param bank: the bank to check
+        :param account_id: the account ID
+        :return: tuple of (currency, amount)
+        :rtype: tuple
+        """
+        token = self.get_key(bank)
+        headers = {"Authorization": f"Bearer {token}"}
+        path = f"{settings.TrueLayer.DataBase}/accounts/{account_id}/balance"
+        r = requests.get(path, headers=headers)
+        try:
+            obj = AccountBalancesRoot.from_json(r.content)
+        except ValidationError as err:
+            self.log.error(f"Validation error: {err}")
+            return
+        parsed = obj.to_dict()["results"]
+        total = 0
+        currency = None
+        for entry in parsed:
+            if currency:
+                if not currency == entry["currency"]:
+                    self.log.error("Different currencies in balance query.")
+                    return
+            total += entry["available"]
+            currency = entry["currency"]
+        return (currency, total)
+
+    def get_total_map(self):
+        """
+        Return a dictionary keyed by currencies with the amounts as values.
+        :return: dict keyed by currency, values are amounts
+        :rtype: dict
+        """
+        totals = {}
+        for bank in self.banks:
+            for account_id in self.banks[bank]:
+                currency, amount = self.get_balance(bank, account_id)
+                if not amount:
+                    continue
+                if currency in totals:
+                    totals[currency] += amount
+                else:
+                    totals[currency] = amount
+        return totals