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How To Generate and Verify OTP Codes Using Python and pyotp

#python #security #webdev #api

Hi πŸ™‚πŸ–

In this post, I will share with you How To Generate and Verify OTP Codes Using Python and pyotp.

PyOTP is a Python library for generating and verifying one-time passwords. It can be used to implement two-factor (2FA) or multi-factor (MFA) authentication methods in web applications and in other systems that require users to log in.

Step 1

Install pyotp

pip install pyotp
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Step 2

Generate secret key

import pyotp print(pyotp.random_base32())
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Result 

KDLZXFSPUQQPFG2HUFZNRHBTWJNZUATJ
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Step 3

Use this secret key to generate OTP codes

otp = pyotp.TOTP(s='KDLZXFSPUQQPFG2HUFZNRHBTWJNZUATJ') print(otp.now())
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Result 

088644
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Step 4

verify OTP Codes

otp.verify(otp.now())
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Result 

True
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print(otp.now()) # 294950 time.sleep(30) print(otp.verify('294950'))
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verify code after 30s this will return False because this code expired

Generate QRCode to use it in Google Authenticator, Authy, or another compatible app. Users can set up auth tokens in their apps easily by using their phone camera to scan otpauth:// QR codes provided by PyOTP.

You can use any browser extinction like:
https://chromewebstore.google.com/detail/%D9%85%D8%B5%D8%A7%D8%AF%D9%82%D8%A9/bhghoamapcdpbohphigoooaddinpkbai

Install pyqrcode

pip install pyqrcode
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import pyqrcode secret_key = 'KDLZXFSPUQQPFG2HUFZNRHBTWJNZUATJ' auth_data = pyotp.TOTP(s = secret_key).provisioning_uri( name = 'user123@test.com', issuer_name = 'Secure APP', ) qr = pyqrcode.create(auth_data) qr.png('qr.png')
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Result

Image description

I used Google Authenticator

 otp = pyotp.TOTP(s='KDLZXFSPUQQPFG2HUFZNRHBTWJNZUATJ') otp_code = '087035' # from Google Authenticator  print(otp.verify(otp_code))
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Result 

True
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Note

"After 30 seconds, this code will expire."

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