OAuth 1a - Appendix A.5.1. Generating Signature Base String - Implementation in Python #python #oauth #sha1

oauth1_signature_python_example.py

"""
Github @realFranco

Testing OAuth1a
"""

def test_compose_oauth1a_signature() -> None:
    """
    Reference: https://oauth.net/core/1.0/#sig_base_example

    DISCLAIMER: Keys | data exposed coming from oauth.net/core/1.0

    This function will test oauth signature generation, through the next steps:
        - normalize request parameters
        - create sign key
        - ceate base string
        - generate key using sha1 be default or the required by the client (sha256 for example)
    """
    expected_base_string = 'GET&http%3A%2F%2Fphotos.example.net%2Fphotos&file%3Dvacation.jpg%26oauth_consumer_key%3Ddpf43f3p2l4k3l03%26oauth_nonce%3Dkllo9940pd9333jh%26oauth_signature_method%3DHMAC-SHA1%26oauth_timestamp%3D1191242096%26oauth_token%3Dnnch734d00sl2jdk%26oauth_version%3D1.0%26size%3Doriginal'
    expected_oauth_signture = 'tR3+Ty81lMeYAr/Fid0kMTYa/WM='

    http = 'GET'
    url = 'http://photos.example.net/photos'
    # Sort keys
    params = {
        'file': 'vacation.jpg',
        'oauth_consumer_key': 'dpf43f3p2l4k3l03',
        'oauth_nonce': 'kllo9940pd9333jh',
        'oauth_signature_method': 'HMAC-SHA1',
        'oauth_timestamp': '1191242096',
        'oauth_token': 'nnch734d00sl2jdk',
        'oauth_version': '1.0',
        'size': 'original'
    }
    params = urlencode(params)

    base_string = signature_base_string(
        http_method=http,
        base_str_uri=url,
        normalized_encoded_request_parameters=params
    )
    is_equal = base_string == expected_base_string
    print(f'base string ok: {is_equal}')

    consumer_secret = 'kd94hf93k423kf44'
    consumer_key = 'pfkkdhi9sl3r4s00'
    sign_key = f'{consumer_secret}&{consumer_key}'

    base_string = base_string.encode('utf-8')
    sign_key = sign_key.encode('utf-8')
    
    # temp = hmac.new(base_string, sign_key, hashlib.sha1).hexdigest()
    temp = hmac.new(sign_key, base_string, hashlib.sha1).hexdigest()
    oauth_signature = b64encode(binascii.unhexlify(temp))  # bytes
    is_equal = oauth_signature.decode() == expected_oauth_signture
    print(f'oauth signature ok: {is_equal}')

    print(oauth_signature)

test_compose_oauth1a_signature()

# Prints
base string ok: True
oauth signature ok: True
b'tR3+Ty81lMeYAr/Fid0kMTYa/WM='