(CkPython) Get Access Token using a Pre-Created JSON Web Token

Demonstrates how to get an access token using a pre-created JSON Web Token (JWT).

For more information, see https://developer.abnamro.com/get-started#headingFive

Chilkat Python Downloads install with pip pip3 install chilkat or download... Python Module for Windows, MacOS, Linux, Alpine Linux, Solaris

import sys
import chilkat

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# We're going to duplicate this CURL statement:
# curl -X POST https://api-sandbox.abnamro.com/v1/oauth/token \
# -H "Content-Type: application/x-www-form-urlencoded" \
# -H "API-Key: xxxxxx" \
# -d 'client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer&grant_type=client_credentials&client_assertion=eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ4eHh4eHgiLCJleHAiOiIxNDk5OTQ3NjY4IiwiaXNzIjoibWUiLCJhdWQiOiJodHRwczovL2F1dGgtc2FuZGJveC5hYm5hbXJvLmNvbS9vYXV0aC90b2tlbiJ9.jGwHKG_YjgKpR8NPpaLu6nJ97obeP2vcxg6fOWBKdJ0&scope=tikkie'

# Load our pre-creaed private key PEM file.
# Note: Please share your public key along with your app name and developer email id at api.support@nl.abnamro.com. 
# Token generation will not work unless public key is associated with your app.
privkey = chilkat.CkPrivateKey()

success = privkey.LoadPemFile("qa_data/pem/abnAmroPrivateKey.pem")
if (success == False):
    print(privkey.lastErrorText())
    sys.exit()

# Create the JWT.
jwt = chilkat.CkJwt()

# Create the header:
# {
#     "typ": "JWT",
#     "alg": "RS256"
# }
jsonHeader = chilkat.CkJsonObject()
jsonHeader.UpdateString("typ","JWT")
jsonHeader.UpdateString("alg","RS256")

# Create the payload:
# {
#     "nbf": 1499947668,
#     "exp": 1499948668,
#     "iss": "me",
#     "sub": "anApiKey",
#     "aud": "https://auth-sandbox.abnamro.com/oauth/token"
# }
jsonPayload = chilkat.CkJsonObject()

curDateTime = jwt.GenNumericDate(0)

# Set the "not process before" timestamp to now.
success = jsonPayload.AddIntAt(-1,"nbf",curDateTime)

# Set the timestamp defining an expiration time (end time) for the token
# to be now + 1 hour (3600 seconds)
success = jsonPayload.AddIntAt(-1,"exp",curDateTime + 3600)

jsonPayload.UpdateString("iss","me")
jsonPayload.UpdateString("sub","anApiKey")
jsonPayload.UpdateString("aud","https://auth-sandbox.abnamro.com/oauth/token")

# Produce the smallest possible JWT:
jwt.put_AutoCompact(True)

jwtStr = jwt.createJwtPk(jsonHeader.emit(),jsonPayload.emit(),privkey)
if (jwt.get_LastMethodSuccess() != True):
    print(jwt.lastErrorText())
    sys.exit()

http = chilkat.CkHttp()

req = chilkat.CkHttpRequest()
req.AddParam("client_assertion_type","urn:ietf:params:oauth:client-assertion-type:jwt-bearer")
req.AddParam("grant_type","client_credentials")
req.AddParam("client_assertion",jwtStr)
req.AddParam("scope","tikkie")

# resp is a CkHttpResponse
resp = http.PostUrlEncoded("https://api-sandbox.abnamro.com/v1/oauth/token",req)
if (http.get_LastMethodSuccess() == False):
    print(http.lastErrorText())
    sys.exit()

if (resp.get_StatusCode() != 200):
    print(resp.bodyStr())

    sys.exit()

# Get the JSON result:
# {
#     "access_token": "{your access token}",
#     "expires_in": "{duration of validity in seconds}",
#     "scope": "{scope(s) for which the access token is valid}",
#     "token_type": "{it is always Bearer}"
# }
json = chilkat.CkJsonObject()
json.Load(resp.bodyStr())
print("access_token: " + json.stringOf("access_token"))
print("token_type: " + json.stringOf("token_type"))
print("expires_in: " + json.stringOf("expires_in"))
print("scope: " + json.stringOf("scope"))