CS50 PSET 9 Finance "sell handles valid sale: expected to find "56.00" in page, but it wasn't found"

Question

I already looked through every post I could find on this topic but nothing seemed to work for me yet. I have tried to recreate the error by: creating a new account, buying 4 shares of 'AAAA', then selling 2 of those shares and checking if the result is correct (TOTAL: $56.00, CASH: $9,944.00). This does seem to work so I am very confused and honestly a bit frustrated why check50 wont let me on :-( I also checked if the amount is displayed in the dollar format in index, that seems to be the case as well.

Here is my code for app.py:

import os
import time
from cs50 import SQL
from flask import Flask, flash, redirect, render_template, request, session
from flask_session import Session
from werkzeug.security import check_password_hash, generate_password_hash

from helpers import apology, login_required, lookup, usd

# Configure application
app = Flask(__name__)

# Custom filter
app.jinja_env.filters["usd"] = usd

# Configure session to use filesystem (instead of signed cookies)
app.config["SESSION_PERMANENT"] = False
app.config["SESSION_TYPE"] = "filesystem"
Session(app)

# Configure CS50 Library to use SQLite database
db = SQL("sqlite:///finance.db")


@app.after_request
def after_request(response):
    """Ensure responses aren't cached"""
    response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
    response.headers["Expires"] = 0
    response.headers["Pragma"] = "no-cache"
    return response


@app.route("/")
@login_required
def index():
    """Show portfolio of stocks"""
    # create table summarizing:
    # owned stocks, number of shares owned, current stock price, total value
    # current cash balance, grand total (stocks+cash value)
    user_id = session["user_id"]
    userdatabase = db.execute("SELECT cash as c FROM users WHERE id = ?", user_id)
    transactiondatabase = db.execute("SELECT stocksymbol, SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, 'buy')

    # TODO: the way the prices are calculated need to be changed:
    # 1. for each stock, calculate how many shares have been bought (ever) and how many shares have been sold (ever)
    # --> bought - sold = currently held shares of that stock

    # another database call for distinct stock symbol
    # 2. sum of value of each stock: currentlyhelshares * individualstockprice

    # Too direct those informations to the html file, they must be saved in four different dictionaries containing: symbol, sharesheld, individualprice, totalvalue
    # the dicts are actually lists because there are no keys to the values

    allinkldict = []
    totalvaluedict = []
    totalvalue = 0
    for stock in transactiondatabase:
        # fill each dictionary with the corresponding value for the actual stock
        stockprice = lookup(stock['stocksymbol'])

        # shares owned at the moment
        sharessold = db.execute("SELECT stocksymbol, SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND stocksymbol = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, stock['stocksymbol'], 'sell')
        if not sharessold:
            sharessold = [{"nsharesowned": 0}]
        if stock['nsharesowned']-sharessold[0]['nsharesowned'] != 0:
            if not sharessold:
                tempprice = stock['nsharesowned']
                dictnewelement = {"symbol": stock['stocksymbol'], "sharesheld": (
                    stock['nsharesowned']), "stockprice": stockprice['price'], "totalvalue": (stock['nsharesowned']) * stockprice['price']}
                totalvalue += (stock['nsharesowned']) * stockprice['price']

            else:
                tempprice = stock['nsharesowned']
                dictnewelement = {"symbol": stock['stocksymbol'], "sharesheld": (stock['nsharesowned'] - (
                    sharessold[0]['nsharesowned'])), "stockprice": stockprice['price'], "totalvalue": (stock['nsharesowned'] - sharessold[0]["nsharesowned"]) * stockprice['price']}
                totalvalue += ((stock['nsharesowned']-(sharessold[0]['nsharesowned'])) * stockprice['price'])

            totalvaluedict.append((stock['nsharesowned'] - tempprice) * stockprice['price'])
            allinkldict.append(dictnewelement)

    countcash = userdatabase[0]['c']

    counttotal = totalvalue + countcash
    return render_template("index.html", userdatabase=userdatabase, transactiondatabase=transactiondatabase, counttotal=counttotal, countcash=countcash, allinkldict=allinkldict)


@app.route("/buy", methods=["GET", "POST"])
@login_required
def buy():
    """Buy shares of stock"""
    # input 1: stock symbol <-- apology if blank/nonexistent
    # input 2: number of shares <-- apology if negative
    # direct input to buy
    # redirect to homepage
    # check if user has enough cashF
    # keep track of bought shares in a new table in finance

    if request.method == "POST":
        Sharesymbol = request.form.get("symbol")
        Sharesymbol = Sharesymbol.upper()

        numberofshares = request.form.get("shares")

        if not numberofshares.isnumeric():
            return apology("Please enter a number regarding how many stocks you want to sell.")
        if Sharesymbol is not None:
            shareinformation = lookup(Sharesymbol)
            if shareinformation is None:
                return apology("Please enter a valid stock symbol")
        if Sharesymbol is None or Sharesymbol == "":
            return apology("Please enter valid stock symbol.")

        if numberofshares is None or float(numberofshares) < 1 or float(numberofshares) % 1 != 0:
            return apology("Please enter the number of stocks you want to purchase. The number must be greater than zero.")

        usercurrentcash = db.execute("SELECT cash FROM users WHERE id = ?", session["user_id"])
        if usercurrentcash is not None and float(usercurrentcash[0]["cash"]) <= shareinformation['price'] * float(numberofshares):
            return apology("Not enough cash to execute transaction.")

        else:
            # add buy to transaction table
            user_id = session["user_id"]
            db.execute("INSERT INTO transactions (user_id, stocksymbol, stockprice, sharesbought, transactiontype) VALUES (?,?,?,?,?)",
                       user_id, Sharesymbol, shareinformation['price'], numberofshares, "buy")

            # reduce customer cash by cash used to buy shares
            newcash = usercurrentcash[0]["cash"] - shareinformation['price'] * float(numberofshares)
            db.execute("UPDATE users SET cash = ? WHERE id = ?", newcash, user_id)
            return redirect("/")
    else:
        return render_template("buy.html")


@app.route("/history")
@login_required
def history():
    """Show history of transactions"""
    user_id = session["user_id"]
    userdatabase = db.execute("SELECT cash as c FROM users WHERE id = ?", user_id)
    transactiondatabase = db.execute(
        "SELECT stocksymbol, sharesbought, transactiontype, stockprice, date as timestamp FROM transactions WHERE user_id = ?", user_id)
    return render_template("history.html", userdatabase=userdatabase, transactiondatabase=transactiondatabase)


@app.route("/login", methods=["GET", "POST"])
def login():
    """Log user in"""

    # Forget any user_id
    session.clear()

    # User reached route via POST (as by submitting a form via POST)
    if request.method == "POST":

        # Ensure username was submitted
        if not request.form.get("username"):
            return apology("must provide username", 403)

        # Ensure password was submitted
        elif not request.form.get("password"):
            return apology("must provide password", 403)

        # Query database for username
        rows = db.execute("SELECT * FROM users WHERE username = ?", request.form.get("username"))

        # Ensure username exists and password is correct
        if len(rows) != 1 or not check_password_hash(rows[0]["hash"], request.form.get("password")):
            return apology("invalid username and/or password", 403)

        # Remember which user has logged in
        session["user_id"] = rows[0]["id"]

        # Redirect user to home page
        return redirect("/")

    # User reached route via GET (as by clicking a link or via redirect)
    else:
        return render_template("login.html")


@app.route("/changepassword", methods=["GET", "POST"])
@login_required
def changepassword():
    user_id = session["user_id"]
    # User reached route via POST (as by submitting a form via POST)
    if request.method == "POST":

        # Ensure password was submitted
        if not request.form.get("oldpassword"):
            return apology("Must provide old password")
        if not request.form.get("newpassword"):
            return apology("Must provide new password")
        if not request.form.get("confirmnewpassword"):
            return apology("Must confirm new password")

        # Query database for username
        rows = db.execute("SELECT * FROM users WHERE id = ?", user_id)

        # Ensure password is correct
        if not check_password_hash(rows[0]["hash"], request.form.get("oldpassword")):
            return apology("Invalid old password")

        # substitute old password in database
        newpassword = request.form.get("newpassword")
        confirmnewpassword = request.form.get("confirmnewpassword")
        if newpassword != confirmnewpassword:
            return apology("Please fill in a matching Password in both boxes.")

        else:
            # add user to the database
            db.execute("UPDATE users SET hash=? WHERE id=?", generate_password_hash(newpassword), user_id)

            # Redirect user to home page
        return redirect("/")

    else:
        return render_template("changepassword.html")


@app.route("/logout")
def logout():
    """Log user out"""

    # Forget any user_id
    session.clear()

    # Redirect user to login form
    return redirect("/")


@app.route("/quote", methods=["GET", "POST"])
@login_required
def quote():
    """Get stock quote."""
    # input: stock symbol
    # if called by OPEN open quoted
    if request.method == "POST":
        Sharesymbol = request.form.get("symbol")
        if Sharesymbol is not None:
            shareinformation = lookup(Sharesymbol)
            if shareinformation is None:
                return apology("Please enter a valid stock symbol")
        if Sharesymbol is None or Sharesymbol == "":
            return apology("Please enter valid stock symbol.")
        else:
            stockinformation = lookup(Sharesymbol)
            return render_template("quoted.html", stockinformation=stockinformation)

    # if called by GET open quote
    else:
        return render_template("quote.html")


"""Register user"""


@app.route("/register", methods=["GET", "POST"])
def register():
    # check wether username is valid
    if request.method == "POST":
        name = request.form.get("username")
        password = request.form.get("password")
        confirmation = request.form.get("confirmation")
        if not request.form.get("username"):
            return apology("Username cannot be blank.")
        usertaken = db.execute("SELECT * FROM users WHERE username = ?", request.form.get("username"))
        if len(usertaken) > 0:
            return apology("Username is already taken")
    # check if passwort and confirmation of password is valid
        if not password or not confirmation or password != confirmation:
            return apology("Please fill in a matching Password in both boxes.")
        else:
            # add user to the database
            db.execute("INSERT INTO users (username, hash) VALUES (?,?)", name, generate_password_hash(password))
            # login the newly registered user
            session["user_id"] = db.execute("SELECT * FROM users WHERE username = ?", name)[0]["id"]

            # Redirect user to home page
        return redirect("/")
    else:
        return render_template("register.html")


@app.route("/sell", methods=["GET", "POST"])
@login_required
def sell():
    """Sell shares of stock"""
    # input 1: stock symbol, form: select menu (name=symbol)
    # -> apology if: no stock selected, no shares of that stock owned
    # input 2: number of shares, form: text field with name being shares
    # -> apology if: input not positive integer, user does not own that many shares of stock
    # submit input with post to sell
    # subtract sold shares from number of shares currently held by user
    # redirect user to homepage

    user_id = session["user_id"]
    if request.method == "POST":
        numbershares = request.form.get("shares")
        stockselected = request.form.get("symbol")
        if not numbershares:
            return apology("Enter the number of shares you want to sell.")
        if not stockselected:
            return apology("Enter a valid stock symbol.")
        stocksymbolpre = ""
        stocksymbolpost = ""
        # extract the stock from stockselected
        for symbol in stockselected:
            if symbol == "'" or symbol == "{" or symbol == "}" or symbol == ":":
                continue
            else:
                stocksymbolpre += symbol
        isspace = False
        for symbol in stocksymbolpre:
            if isspace:
                stocksymbolpost += symbol
            if symbol == " ":
                isspace = True

        sharestotal = db.execute(
            "SELECT DISTINCT(stocksymbol), SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND stocksymbol = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, stocksymbolpost, 'buy')
        sharessold = db.execute(
            "SELECT DISTINCT(stocksymbol), SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND stocksymbol = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, stocksymbolpost, 'sell')
        if not sharestotal:
            return apology("Internal error.")
        if not sharessold:
            sharescurrentlyheld = sharestotal[0]["nsharesowned"]
        else:
            sharescurrentlyheld = sharestotal[0]["nsharesowned"] - sharessold[0]["nsharesowned"]

        # check if user has selected stock to sell
        if not numbershares:
            return apology("Please enter the amount of shares you want to sell")
        # check if user has enough shares to sell
        if int(numbershares) > sharescurrentlyheld:
            return apology("The number of shares you want to sell must be lower or equal to the shares you possess at the moment.")
        # check if the number of shares is positive
        if int(numbershares) < 1:
            return apology("The number of shares you want to sell must be higher or equal to 1.")

        # subtract sold shares from number of shares currently held by user
            # --> create new table and keep track there of how many stocks a user holds
            # new column in transactions named transactiontype of type String, it can be 'buy' when a share is bought and 'sell' when a share is sold

        # keep hold of transaction in database
        # -> extract the share name
        shareinformation = lookup(stocksymbolpost)
        db.execute("INSERT INTO transactions (user_id, stocksymbol, stockprice, sharesbought, transactiontype) VALUES (?,?,?,?,?)",
                   user_id, stocksymbolpost, shareinformation['price'], numbershares, 'sell')

        # increase customer cash by cash gotten by selling shares
        shareinformation = lookup(stocksymbolpost)
        usercurrentcash = db.execute("SELECT cash FROM users WHERE id = ?", session["user_id"])
        newcash = usercurrentcash[0]["cash"] + shareinformation['price'] * float(numbershares)
        db.execute("UPDATE users SET cash = ? WHERE id = ?", newcash, user_id)
        # redirect user to homepage
        return redirect("/")

    else:
        # only show shares that user currently possesses
        transactiondatabase = db.execute("SELECT stocksymbol, SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, 'buy')
        shareshelddict = []
        for stock in transactiondatabase:
            sharessold = db.execute("SELECT stocksymbol, SUM(sharesbought) as nsharesowned FROM transactions WHERE user_id = ? AND stocksymbol = ? AND transactiontype = ? GROUP BY stocksymbol", user_id, stock['stocksymbol'], 'sell')
            if not sharessold:
                sharessold = [{"nsharesowned": 0}]
            if stock['nsharesowned']-sharessold[0]['nsharesowned'] != 0:
                dictnewelement = {"symbol": stock['stocksymbol']}
                shareshelddict.append(dictnewelement)


        return render_template("sell.html", shareshelddict=shareshelddict)

And my code for index.html:

{% block title %}
    Home
{% endblock %}

    {% block main %}
    <h2>Your current portfolio:</h2>
    <head>
        <style>
        table {
          font-family: arial, sans-serif;
          border-collapse: collapse;
          width: 100%;
        }

        td, th {
          border: 1px solid #dddddd;
          text-align: left;
          padding: 8px;
        }

        tr:nth-child(even) {
          background-color: #dddddd;
        }
        </style>
        </head>
                    <table>
                        <thead>
                            <tr>
                                <td>Symbol</td>
                                <th>Shares</th>
                                <th>Price</th>
                                <th>TOTAL</th>
                            </tr>
                        </thead>
                        <tbody>
                        <!-- loop through database and show result-->
                        <ul>
                            <!-- stocks -->
                            {% for symbol in allinkldict %}
                            <tr>
                                <th>{{symbol['symbol']}}</th>
                                <th>{{symbol['sharesheld']}}</th>
                                <th>{{symbol['stockprice'] | usd}}</th>
                                <th>{{symbol['totalvalue'] | usd}}</th>
                            {% endfor %}

                            </tr>

                        </ul>
        <table>
            <tr>
                <th>
                </th>
            </tr>
                                        <!-- Cash -->
                                        <tr>
                                            <th>Cash </th>
                                            <td>{{countcash | usd}}</td>
                                        </tr>
                                        <!-- Total, calculate in python and print out here  -->
                                        <tr>
                                            <th>TOTAL</th>
                                            <td>{{counttotal | usd}}</td>
                                        </tr>
        </table>
                        </tbody>
                    </table>
{% endblock %}

I would really appreciate your help on this to be able to continue with the final project. Many thanks in advance!

Answer 1

I had an error in sell.html where I was returning values in the format "'symbol': 'stocksymbol'" instead of just the actual symbol, which I then tried to correct in my python code to only show the symbol, which technically worked but check50 did not like. I fixed my sell.html code to return only the stocksymbol to POST and deleted the parts of the code where I formatted the POST return in a special way and the program now passes all check50 tests.