app.py

# importing the required libraries
from cs50 import SQL
from flask import Flask, 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

# initialising the flask app
# Configure application
# Configure application
app = Flask(__name__)

# Ensure templates are auto-reloaded
app.config["TEMPLATES_AUTO_RELOAD"] = True

# 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:///files.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", 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("/logout")
def logout():
    """Log user out"""

    # Forget any user_id
    session.clear()

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

@app.route("/")
@login_required
def editor():
    return render_template("/editor.html")


@app.route("/register", methods=["GET", "POST"])
def register():
    """Register user"""
    if request.method == "GET":
        return render_template("/register.html")

    else:

        usedname = db.execute("SELECT username FROM users")
        wname = request.form.get("username")
        for i in usedname:
            if wname in i["username"] or not wname:
                return apology("Username error. Must be already taken or it not provided or no password provided.")

        if request.form.get("password") != request.form.get("confirmation") or not request.form.get("password"):
            return apology("Passwords don't match or no password provided")

        password = request.form.get("password")

        hpassword = generate_password_hash(
            password, method='pbkdf2:sha256', salt_length=8)

        db.execute("INSERT INTO USERS (username, hash) VALUES (?,?)",
                   wname, hpassword)

        return redirect("/")