Python encoded message with HMAC-SHA256

Question

I try to encoded message with HMAC-SHA256 in python according to instructions

import hmac
import hashlib

nonce = 1234
customer_id = 123232
api_key = 2342342348273482374343434
API_SECRET = 892374928347928347283473

message = nonce + customer_id + api_key
signature = hmac.new(
    API_SECRET,
    msg=message,
    digestmod=hashlib.sha256
).hexdigest().upper()

but I get this

Traceback (most recent call last): File “gen.py”, line 13, in

digestmod=hashlib.sha256 File “/usr/lib/python2.7/hmac.py”, line 136, in new
return HMAC(key, msg, digestmod) File “/usr/lib/python2.7/hmac.py”, line 71, in init
if len(key) > blocksize: TypeError: object of type ‘long’ has no len()

Does anyone have any idea why crashes?

Asked By: Oana Andone

||

Source

Answer 1

You’re using numbers where the api expects a string/bytes.

# python 2
import hmac
import hashlib

nonce = 1234
customer_id = 123232
api_key = 2342342348273482374343434
API_SECRET = 892374928347928347283473

message = '{} {} {}'.format(nonce, customer_id, api_key)
signature = hmac.new(
    str(API_SECRET),
    msg=message,
    digestmod=hashlib.sha256
).hexdigest().upper()

print signature

Answered By: Rz Mk

Answer 2

If you want to execute in python3 you should do the following:

#python 3
import hmac
import hashlib

nonce = 1
customer_id = 123456
API_SECRET = 'thekey'
api_key = 'thapikey'

message = '{} {} {}'.format(nonce, customer_id, api_key)

signature = hmac.new(bytes(API_SECRET , 'latin-1'), msg = bytes(message , 'latin-1'), digestmod = hashlib.sha256).hexdigest().upper()
print(signature)

Answered By: nunodsousa

Python encoded message with HMAC-SHA256

Question:

Answers: