(Visual FoxPro) ABN AMRO Create Signed JSON Web Token

Demonstrates how to create a signed JWT to be used for authenticating requests to the ABN AMRO REST API's.

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL loRsa
LOCAL lnSuccess
LOCAL loPrivkey
LOCAL loPubkey
LOCAL loJwt
LOCAL loJsonHeader
LOCAL loJsonPayload
LOCAL lnCurDateTime
LOCAL lcJwtStr

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

* Create public/private key pair (RSA)
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Rsa')
loRsa = CreateObject('Chilkat.Rsa')

* Generate a 2048-bit key.
lnSuccess = loRsa.GenerateKey(2048)
IF (lnSuccess <> 1) THEN
    ? loRsa.LastErrorText
    RELEASE loRsa
    CANCEL
ENDIF

* Export the key to PEM files.
* Write one PEM file for the private key, and one for the public key.
loPrivkey = loRsa.ExportPrivateKeyObj()
lnSuccess = loPrivkey.SavePemFile("qa_data/pem/abnAmroPrivateKey.pem")

loPubkey = loRsa.ExportPublicKeyObj()
lnSuccess = loPubkey.SavePemFile(1,"qa_data/pem/abnAmroPublicKey.pem")
* 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.

* Create the JWT.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Jwt')
loJwt = CreateObject('Chilkat.Jwt')

* Create the header:
* {
*     "typ": "JWT",
*     "alg": "RS256"
* }
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJsonHeader = CreateObject('Chilkat.JsonObject')
loJsonHeader.UpdateString("typ","JWT")
loJsonHeader.UpdateString("alg","RS256")

* Create the payload:
* {
*     "nbf": 1499947668,
*     "exp": 1499948668,
*     "iss": "me",
*     "sub": "anApiKey",
*     "aud": "https://auth-sandbox.abnamro.com/oauth/token"
* }
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJsonPayload = CreateObject('Chilkat.JsonObject')

lnCurDateTime = loJwt.GenNumericDate(0)

* Set the "not process before" timestamp to now.
lnSuccess = loJsonPayload.AddIntAt(-1,"nbf",lnCurDateTime)

* Set the timestamp defining an expiration time (end time) for the token
* to be now + 1 hour (3600 seconds)
lnSuccess = loJsonPayload.AddIntAt(-1,"exp",lnCurDateTime + 3600)

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

* Produce the smallest possible JWT:
loJwt.AutoCompact = 1

lcJwtStr = loJwt.CreateJwtPk(loJsonHeader.Emit(),loJsonPayload.Emit(),loPrivkey)
IF (loJwt.LastMethodSuccess <> 1) THEN
    ? loJwt.LastErrorText
    RELEASE loRsa
    RELEASE loJwt
    RELEASE loJsonHeader
    RELEASE loJsonPayload
    CANCEL
ENDIF

RELEASE loPrivkey
RELEASE loPubkey

* Here is the JWT:
? lcJwtStr

RELEASE loRsa
RELEASE loJwt
RELEASE loJsonHeader
RELEASE loJsonPayload