karixsign.py

from hashlib import sha512
import base64
import hmac


def compute_signature(uri, params, token):
    token = token.encode("utf-8")
    s = uri
    if len(params) > 0:
        for k, v in sorted(params.items()):
            if v:
                s += k + str(v)

    mac = hmac.new(token, s.encode("utf-8"), sha512)
    computed = base64.b64encode(mac.digest())
    return computed.strip()