MongoDB driver can now handle portfolio functions

- No watchlist functionality yet

mongo.py

@@ -0,0 +1,56 @@
+from mongoengine import *
+from config import config
+from bson import Decimal128
+from decimal import Decimal
+import yfi
+
+connect(config["database"])
+
+
+class Portfolio(Document):
+    user = StringField(required=True)
+    stocks = DictField(default={})
+
+
+class Watchlist(Document):
+    user = StringField(max_length=200, required=True)
+    stocks = DictField(required=True, default={})
+
+
+def user_check(user):
+    # Will create empty portfolio for new users
+    if not Portfolio.objects(user=user):
+        portfolio = Portfolio(user=user)
+        portfolio.save()
+
+
+
+# Portfolio Stuff
+def get_stocks(user):
+    user_check(user)
+    return Portfolio.objects.get(user=user).stocks
+
+def add_stock(user, stock, amount):
+    user_check(user)
+    amount = Decimal(amount)
+    portfolio = Portfolio.objects.get(user=user)
+
+    if not ( se := yfi.stock_exists(stock)):
+        # Stock ticker does not exist on yahoo finance
+        return False
+
+    if stock in portfolio.stocks.keys():
+        portfolio.stocks[stock] = Decimal128(
+            amount + portfolio.stocks[stock].to_decimal()
+        )
+    else:
+        portfolio.stocks[stock] = Decimal128(amount)
+    portfolio.save()
+    return True
+
+def delete_stock(user, stock):
+    user_check(user)
+    portfolio = Portfolio.objects.get(user=user)
+    if stock in portfolio.stocks.keys():
+        del portfolio.stocks[stock]
+        portfolio.save()