How to remove \r character from the getpass prompt

Question

I have written a code which actually matches the patter RegEx in Python. I have used getpass library to prompt the user to enter the password.But if the user enters the wrong password[say 'HH'-which is invalid password].Once the user hits enter after typing the password,the get pass is taking "HH" and "enter as \r" [two different inputs]. Now I need a way to find out how to seperate '\r' from being passed as an input.

I have tried using strip function to remove '\r' but was unsuccessful

import getpass
import re
loopVar=True

while loopVar:

    password = getpass.getpass("Enter your password: ")
    password.rstrip('\r')
    pattern=re.match(r'(?=.{5,32}$)(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9])(?=.*[^A-Za-z0-9])',password)

    if pattern:
        print ("The password mateches as per standards")
        loopVar=False
    else:
        print ("The password "+ password +" is not as per rules ")

Enter your password:
The password hh is not as per rules
Enter your password:(this is taking \r as input character and I dont need this)
The password  is not as per rules

Enter your password:[Prompting user to input]

Perhaps add another negative lookahead to assert that there can not be a whitespace char `(?!.*\s)` — The fourth bird, Apr 05 '19 at 06:08
If u meant to add negative lookahead in the reg ex patter ,I tried but did not work .Thanks for the suggestion — Akash, Apr 05 '19 at 08:59

Mahmoud Elshahat · Answer 1 · 2019-04-05T06:56:08.627

1

You are too close :)

modify your code from:

password.rstrip('\r')

to

password = password.rstrip('\r')

Explanation: from python docs,

str.rstrip([chars]): Return a copy of the string with trailing characters removed.

because string is immutable in python so you need to assign this copy to your variable again

Edit: responding to the issue of getting double entries when user write password and hit enter, one entry has a password string and second is bare enter code '\r', you can add if statement to filter out second input example:

password = getpass.getpass("Enter your password: ")

if password != '\r':  # filter out echo input
    password.rstrip('\r')
    pattern=re.match(r'(?=.{5,32}$)(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9])(?=.*[^A-Za-z0-9])',password)

    if pattern:
        print ("The password mateches as per standards")
        loopVar=False
    else:
        print ("The password "+ password +" is not as per rules ")

edited Apr 05 '19 at 06:56

answered Apr 05 '19 at 06:10

Mahmoud Elshahat

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Thanks mate!!! But still I am facing the same issue .Its still taking enter as a new input – Akash Apr 05 '19 at 06:22
do you mean you want to neglect enter only input i.e. if user hit Enter with a blank password? – Mahmoud Elshahat Apr 05 '19 at 06:36
@Akash i edited the answer see if it solves your problem of getting an extra enter as a new input – Mahmoud Elshahat Apr 05 '19 at 06:57
I am still seeing \r being taken as input... I am not sure ,why this extra command ['\r' in this case ] is being taken automatically. Enter your password: The password dd is not as per rules Enter your password: The password is not as per rules Enter your password:[prompting agian to enter valid input] This is what I am seeing... – Akash Apr 05 '19 at 08:53

How to remove \r character from the getpass prompt

1 Answers1