PowerBuilder

Verify JWT Using HS256, HS384, or HS512

See more JSON Web Token (JWT) Examples

Demonstrates how to verify a JWT that was signed using HS256, HS384, or HS512. (HS256 is JWT's acronym for HMAC-SHA256.)

This example verifies the signature. It also does the following:

• Checks to see if the time constraints ("nbf" and "exp") are valid.
• Recovers the original JOSE header.
• Recovers the original claims JSON.

PowerBuilder

integer li_rc
long li_Success
oleobject loo_Jwt
string ls_Token
long li_SigVerified
long li_Leeway
long li_BTimeValid
string ls_Payload
oleobject loo_Json
string ls_JoseHeader

li_Success = 0

//  Demonstrates how to verify 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.

loo_Jwt = create oleobject
li_rc = loo_Jwt.ConnectToNewObject("Chilkat.Jwt")
if li_rc < 0 then
    destroy loo_Jwt
    MessageBox("Error","Connecting to COM object failed")
    return
end if

ls_Token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJodHRwOi8vZXhhbXBsZS5vcmciLCJzdWIiOiJKb2huIiwiYXVkIjoiaHR0cDovL2V4YW1wbGUuY29tIiwiaWF0IjoxNDYzNDMxODEyLCJuYmYiOjE0NjM0MzE4MTIsImV4cCI6MTQ2MzQzNTQxMn0.SHnMJ11qJH5pbp22YchT_9fL2HIx0koHiUHLG67_foU"

//  First verify the signature.
//  The password used to create this JWT was "secret".
li_SigVerified = loo_Jwt.VerifyJwt(ls_Token,"secret")
Write-Debug "with correct password: " + string(li_SigVerified)

//  Now try with a different password:
li_SigVerified = loo_Jwt.VerifyJwt(ls_Token,"secret2")
Write-Debug "with incorrect password " + string(li_SigVerified)

//  Let's see if the time constraints, if any, are valid.
//  The above JWT was created on the afternoon of 16-May-2016, with an expiration of 1 hour.
//  If the current system time is before the "nbf" time, or after the "exp" time,
//  then IsTimeValid will return false/0.
//  Also, we'll allow a leeway of 60 seconds to account for any clock skew.
//  Note: If the token has no "nbf" or "exp" claim fields, then IsTimeValid is always true.
li_Leeway = 60
li_BTimeValid = loo_Jwt.IsTimeValid(ls_Token,li_Leeway)
Write-Debug "time constraints valid: " + string(li_BTimeValid)

//  Now let's recover the original claims JSON (the payload).
ls_Payload = loo_Jwt.GetPayload(ls_Token)
//  The payload will likely be in compact form:
Write-Debug ls_Payload

//  We can format for human viewing by loading it into Chilkat's JSON object
//  and emit.
loo_Json = create oleobject
li_rc = loo_Json.ConnectToNewObject("Chilkat.JsonObject")

li_Success = loo_Json.Load(ls_Payload)
loo_Json.EmitCompact = 0
Write-Debug loo_Json.Emit()

//  We can recover the original JOSE header in the same way:
ls_JoseHeader = loo_Jwt.GetHeader(ls_Token)
//  The payload will likely be in compact form:
Write-Debug ls_JoseHeader

//  We can format for human viewing by loading it into Chilkat's JSON object
//  and emit.
li_Success = loo_Json.Load(ls_JoseHeader)
loo_Json.EmitCompact = 0
Write-Debug loo_Json.Emit()


destroy loo_Jwt
destroy loo_Json