(Visual FoxPro) Create JWT Using HS256, HS384, or HS512

Demonstrates how to create a JWT using HS256, HS384, or HS512. (HS256 is JWT's acronym for HMAC-SHA256.) When HMAC is used, the secret is a shared secret (i.e. password) that both client and server know beforehand.

This example also demonstrates how to include time constraints:

• nbf: Not Before Time
• exp: Expiration Time
• iat: Issue At Time

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

LOCAL loJwt
LOCAL loJose
LOCAL lnSuccess
LOCAL loClaims
LOCAL lnCurDateTime
LOCAL lcStrJwt

* Demonstrates how to create an HMAC JWT using a shared secret (password).

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

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

* Build the JOSE header
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJose = CreateObject('Chilkat.JsonObject')
* Use HS256.  Pass the string "HS384" or "HS512" to use a different algorithm.
lnSuccess = loJose.AppendString("alg","HS256")
lnSuccess = loJose.AppendString("typ","JWT")

* Now build the JWT claims (also known as the payload)
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loClaims = CreateObject('Chilkat.JsonObject')
lnSuccess = loClaims.AppendString("iss","http://example.org")
lnSuccess = loClaims.AppendString("sub","John")
lnSuccess = loClaims.AppendString("aud","http://example.com")

* Set the timestamp of when the JWT was created to now.
lnCurDateTime = loJwt.GenNumericDate(0)
lnSuccess = loClaims.AddIntAt(-1,"iat",lnCurDateTime)

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

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

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

lcStrJwt = loJwt.CreateJwt(loJose.Emit(),loClaims.Emit(),"secret")

? lcStrJwt

RELEASE loJwt
RELEASE loJose
RELEASE loClaims