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How do I store an object in a dictionary in Python?

In my password manager prroject, I am trying to code a login function.
In this functtion, if the user's username and password match an account stored in this dictionary, it allows access to their object which has the following attributes: username, password, password_coll.
(The password_coll is a dictionary/collection of the users passwords as values to the website of use as keys).
So as a little stem from my original question, how would I also reference my
This is my first time using OOP approach and it is really frying my brain hahaha.
So I thought of using usernames as keys and the object as the value. But how do I structure this in code?
Any examples would be greatly appreciated.
I did try checking existing questions but they didn't answer my question closely enough. So here we are haha:)
The code block at the bottom is my attempt at testing the output of those methods to see if they return the data in the object. But the result was this message:
"<bound method User.return_pass of <main.User object at 0x0000023419597940>>"
import random
import secrets
import string
class User:
def __init__(self, username, password, password_dict=None) -> None:
self.username = username
self.password = password
self.password_dict = {}
def return_pass(self, password):
return self.password
def __str__(self, password) -> str:
return self.password
def get_creds(self, username, password):
usern = input('Enter username: ')
pwd = input('Enter password: ')
self.username = usern
self.password = pwd
def passGen(self, password_dict): # random password generator
n = int(input('Define password length. Longer passwords are safer.'))
source = string.ascii_letters + string.digits
password = ''.join((secrets.choice(source)) for i in range(n))
print('Password has been generated!')
print('Would you like to save this password? Type y or n: ')
yon = input()
if yon == 'y':
site = input('Please enter the site password is to be used:')
self.password_dict[site] = password
return self.password_dict
u1 = User('dave', 'pass', {})
user_logins = {'dave': u1}
print(user_logins['dave'].return_pass)

User.return_pass is a function, it has to be called:
print(user_logins['dave'].return_pass("password")) where the text "password" is the arg required in the function.
Hope this helps

def login(username, password, user_logins):
if username in user_logins:
user = user_logins[username]
if user.password == password:
return user.password_dict
else:
return "Incorrect password"
else:
return "Username not found"
print(login('dave', 'pass', user_logins))
In your code, you're trying to print the output of a function, but you forgot to actually run the function by adding parentheses at the end. So instead of just printing the function, you need to run it by adding () at the end. Also, the str method in the User class should not take any input, and it should return the value of self.password instead of just 'password'
print(user_logins['dave'].return_pass())

Flask-html : Best way to validate form input

Hello I'm trying to create a web registration form with the flask module. What is the easiest way/module to check if a username contains a certain amount of characters, has numbers, and uppercase letters and how do I loop a form input until a valid username in this case is entered?
#app.route('/register', methods=['POST', 'GET'])
def register():
if request.method == "POST":
username = request.form["username"]
password = request.form["password"]
error = None
if not username:
error = "Username is required."
elif not password:
error = "Password is required."
flash(error)
if error is None:
with open('data.txt', 'a', encoding='utf8') as file:
encoded_password = password.encode()
hash_password = hashlib.sha256(encoded_password).hexdigest()
file.write(username + ' ' + hash_password + '\n')
return redirect(url_for("login"))
return render_template('register.html')

call another function like this (just an example only worrying about the username) and expand the logic as you see fit - determine if they should stay on the registration page based on whether process_registration is True
def verify_user_registration_credentials(username, password):
if not username:
flash_message = "Please enter a username"
process_registration = False
elif len(username) <= 5:
flash_message = "Please enter a username greater than 5 characters"
process_registration = False
else:
for character in username:
if character.isdigit() or character.isupper():
break
process_registration = True # assuming you want them to have either a number or an upper case letter in their username

How can I disable concatenation when using hashlib's update method?

I've written a method for hashing passwords by using hashlib.
I allow the user to send a password through a POST method, which is received by Flask and the password is subsequently hashed so that the hash can be checked against a stored var to see if it's the same.
It works great both when a correct or an incorrect password is sent for the first time.
But if the user sends a wrong password on the first POST and then tries again with the correct password, it fails. (One could also think of it as failing if the first try was a success and the user keeps on trying, but I don't care about that for now.)
I was able to narrow the problem down to hashlibs update function
hash.update(arg)
Update the hash object with the string arg. Repeated calls are equivalent to a single call with the concatenation of all the arguments: m.update(a); m.update(b) is equivalent to m.update(a+b).
I wanted to know how can I disable the concatenation upon repeated calls.
It doesn't matter if it's a hacky workaround.
Here's my code in case it's useful:
h = hashlib.sha256()
VALID_USERNAME = 'admin'
VALID_PASSW_HASH = "210ce034be6d826a451a4261d70494148c5d7101627335ccacf8e00a711bcc5d"
#app.route('/api/queue/auth', methods=['POST'])
def auth():
username = request.json.get('username')
password = request.json.get('password')
if bool(username) is False or bool(password) is False:
return "\nPlease fill in both fields.\n", 400
passwordBytes = password.encode(encoding='UTF-8',errors='strict')
h.update(passwordBytes)
if h.hexdigest() != VALID_PASSW_HASH or username != VALID_USERNAME:
return "\nPlease check your username and password, and try again.\n", 401
r.set('auth', 'true')
return "Access Granted.\n", 200
Additional notes:
the "r.set" line (above the last one) is just because it later does something with Redis.
i've checked that passwordBytes always returns the same encoding when the same password is provided (it's deterministic)
i've also checked that h.hexdigest() is returning something different if the same password is provided on the first try or on another try. So taking into account these two points, we can be sure that the problem lies in h.update(), probably because of the concatenation feature.

Just move the first line out of the global scope into the auth() function:
VALID_USERNAME = 'admin'
VALID_PASSW_HASH = "210ce034be6d826a451a4261d70494148c5d7101627335ccacf8e00a711bcc5d"
#app.route('/api/queue/auth', methods=['POST'])
def auth():
username = request.json.get('username')
password = request.json.get('password')
if bool(username) is False or bool(password) is False:
return "\nPlease fill in both fields.\n", 400
passwordBytes = password.encode(encoding='UTF-8',errors='strict')
h = hashlib.sha256()
h.update(passwordBytes)
if h.hexdigest() != VALID_PASSW_HASH or username != VALID_USERNAME:
return "\nPlease check your username and password, and try again.\n", 401
r.set('auth', 'true')
return "Access Granted.\n", 200
or even better, refactor the hashing of the password to a different function:
VALID_USERNAME = 'admin'
VALID_PASSW_HASH = "210ce034be6d826a451a4261d70494148c5d7101627335ccacf8e00a711bcc5d"
def hash_password(password):
passwordBytes = password.encode(encoding='UTF-8',errors='strict')
h = hashlib.sha256()
h.update(passwordBytes)
return h.hexdigest()
#app.route('/api/queue/auth', methods=['POST'])
def auth():
username = request.json.get('username')
password = request.json.get('password')
if bool(username) is False or bool(password) is False:
return "\nPlease fill in both fields.\n", 400
if hash_password(password) != VALID_PASSW_HASH or username != VALID_USERNAME:
return "\nPlease check your username and password, and try again.\n", 401
r.set('auth', 'true')
return "Access Granted.\n", 200

Can't import a class from another python file

I searched on internet but I still don't understand why my code doesn't work. I have a Python file called Era.py, in this file I have this class:
class input:
def __init__(self, username):
self.username = username
close = ["X", "x"]
print("So, let's start, sweetheart, press X when you want to stop. \n")
user_input = input("")
user_input = user_input.upper()
while user_input not in close:
user_in = Subject(username, user_input)
user_input = input("")
print("Good bye, sweetheart!")
And in another Python file, read_from_database.py I have this:
class oldUser:
def __init__(self, login, password):
self.login = login
self.password = password
results = "SELECT * FROM users WHERE username = '" + login + "'" + " AND password = " + "'" + password + "'"
mycursor.execute(results)
results = mycursor.fetchall()
if not results:
print("User don't exist or wrong login details! \n")
print(add_to_database)
else:
print("Login successfully!")
from Era import input
execute = input(login)
But when I try to import from Era, input, I have this error:
ImportError: cannot import name 'input' from 'Era'
All files are in the same folder and theoretically it should work, 1 week ago it worked

The problem here is that you are overriding the built-in input function of Python, while still trying to use it.
You can see this in the input class of your Era.py file.
This class attempts to use the built-in input function for collecting user_input.
Because of this, attempting to from Era import input will occasionally fail, as Python gets confused about what to do.
Bottom line here is that you should never override any built-in functions (especially if you need them as well) unless you know what you are doing.
To add to this, it is common in Python that class names start with a capital letter and use no underscores, while functions and modules (like Era here) have only lowercase letters and underscores.
So, change your code to the following:
# era.py
class Input:
def __init__(self, username):
self.username = username
close = ["X", "x"]
print("So, let's start, sweetheart, press X when you want to stop. \n")
user_input = input("")
user_input = user_input.upper()
while user_input not in close:
user_in = Subject(username, user_input)
user_input = input("")
print("Good bye, sweetheart!")
# read_from_database.py
from era import Input
class OldUser:
def __init__(self, login, password):
self.login = login
self.password = password
results = "SELECT * FROM users WHERE username = '" + login + "'" + " AND password = " + "'" + password + "'"
mycursor.execute(results)
results = mycursor.fetchall()
if not results:
print("User don't exist or wrong login details! \n")
print(add_to_database)
else:
print("Login successfully!")
execute = Input(login)
You also may want to have a look at your Input class, as it can be simplified in several ways.

Python: Json File Referencing from user Inputs

I'm currently using JSON to make a username/password program but I have a problem with duplicate accounts. I tried to code a way to prevent users from creating usernames that the JSON database already contains, but it doesn't quite work.
Problems:
Asks for the username, doesn't ask for the password even when the file tried is empty
Sometimes says the username already exists, but creates the account duplicate anyway.
What I want the program to do:
Ask for the new username/password
If the username is unique, place the new account in the file
If the username is already owned, don't add the new account and go to the start of the function.
How would I do this efficiently?
This is the code I've tried, but the problems I mentioned make it invalid
def createUser():
global accounts
nUsername = input("Create Username » ")
for item in accounts:
if item[0] == nUsername:
return "Already Exsists!"
else:
nPassword = input("Create Password » ")
entry = [nUsername, nPassword]
accounts.append(entry)
accounts = accounts[:500000]
autoSave()
For anyone wondering, this is what the autosave() function is:
def autoSave():
with open("Accounts.json", "w") as outfile:
json.dump(accounts, outfile)
And this is what the inside of the JSON file looks like:
[["ExampleUsername", "BadPasswrdo14130"]]

There is many mistakes so I will use comment to explain changes:
# you file containt utf8 chars, you need to specify encoding
# coding=utf-8
import os
import json
# I use a dict structure instead of a list for easier retrieval
# you can easily see if an account exist and get its password
# also global keyword is to avoid, so prefer declaring in the global context instead of pushing to the global context
accounts = {}
# if we have a file, deserialize content
if os.path.exists("/tmp/Accounts.json"):
try:
with open("/tmp/Accounts.json") as f:
accounts = dict(json.loads(f.read()))
except:
pass
def createUser():
# input is equivalent to eval(raw_input(... which is not the goal here
nUsername = raw_input("Create Username » ")
# with a dict, no need to iterate through, simply use `in`
if nUsername in accounts.keys():
return createUser()
nPassword = raw_input("Create Password » ")
# this is how you assign the new account
accounts[nUsername] = nPassword
autoSave()
def autoSave():
with open("/tmp/Accounts.json", "w") as outfile:
# we convert here the dict to your list structure
json.dump(list(accounts.iteritems()), outfile)
def existingUser():
eUsername = raw_input("Your Username » ")
ePassword = raw_input("Your Password » ")
for item in accounts:
if eUsername in accounts and accounts[eUsername] == ePassword:
return 'Processing Sucessfully logged into your account!'
else:
return "Login failed"
createUser()

I would do it this way:
# This function will help us to check if the user already exists
def alreadyExist(nUsername):
global accounts
for account in accounts:
if account[0] == nUsername
return True
return False
def createUser():
global accounts
# We declarate nUsername first as None
nUsername = None
# While the username exists, we have to ask the user for the username
while not nUsername or alreadyExist(nUsername):
nUsername = input("Create Username » ")
# We are out of the bucle. The username doesn't exist, we can ask for the password
nPassword = input("Create Password » ")
entry = [nUsername, nPassword]
accounts.append(entry)
accounts = accounts[:500000]
autoSave()

Fixed one issue of my code, but made another. This section was working fine before the chances from #CyrBill
def existingUser():
eUsername = input("Your Username » ")
ePassword = input("Your Password » ")
for item in accounts: #no need for braces
if item[0] == eUsername and item[1] == ePassword:
return 'Processing Sucessfully logged into your account!'
else:
return "Login failed"