(DataFlex) 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

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoRsa
    Boolean iSuccess
    Variant vPrivkey
    Handle hoPrivkey
    Variant vPubkey
    Handle hoPubkey
    Handle hoJwt
    Handle hoJsonHeader
    Handle hoJsonPayload
    Integer iCurDateTime
    String sJwtStr
    String sTemp1
    String sTemp2
    Boolean bTemp1

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

    // Create public/private key pair (RSA)
    Get Create (RefClass(cComChilkatRsa)) To hoRsa
    If (Not(IsComObjectCreated(hoRsa))) Begin
        Send CreateComObject of hoRsa
    End

    // Generate a 2048-bit key.
    Get ComGenerateKey Of hoRsa 2048 To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Export the key to PEM files.
    // Write one PEM file for the private key, and one for the public key.
    Get ComExportPrivateKeyObj Of hoRsa To vPrivkey
    If (IsComObject(vPrivkey)) Begin
        Get Create (RefClass(cComChilkatPrivateKey)) To hoPrivkey
        Set pvComObject Of hoPrivkey To vPrivkey
    End
    Get ComSavePemFile Of hoPrivkey "qa_data/pem/abnAmroPrivateKey.pem" To iSuccess

    Get ComExportPublicKeyObj Of hoRsa To vPubkey
    If (IsComObject(vPubkey)) Begin
        Get Create (RefClass(cComChilkatPublicKey)) To hoPubkey
        Set pvComObject Of hoPubkey To vPubkey
    End
    Get ComSavePemFile Of hoPubkey True "qa_data/pem/abnAmroPublicKey.pem" To iSuccess
    // 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.
    Get Create (RefClass(cComChilkatJwt)) To hoJwt
    If (Not(IsComObjectCreated(hoJwt))) Begin
        Send CreateComObject of hoJwt
    End

    // Create the header:
    // {
    //     "typ": "JWT",
    //     "alg": "RS256"
    // }
    Get Create (RefClass(cComChilkatJsonObject)) To hoJsonHeader
    If (Not(IsComObjectCreated(hoJsonHeader))) Begin
        Send CreateComObject of hoJsonHeader
    End
    Get ComUpdateString Of hoJsonHeader "typ" "JWT" To iSuccess
    Get ComUpdateString Of hoJsonHeader "alg" "RS256" To iSuccess

    // Create the payload:
    // {
    //     "nbf": 1499947668,
    //     "exp": 1499948668,
    //     "iss": "me",
    //     "sub": "anApiKey",
    //     "aud": "https://auth-sandbox.abnamro.com/oauth/token"
    // }
    Get Create (RefClass(cComChilkatJsonObject)) To hoJsonPayload
    If (Not(IsComObjectCreated(hoJsonPayload))) Begin
        Send CreateComObject of hoJsonPayload
    End

    Get ComGenNumericDate Of hoJwt 0 To iCurDateTime

    // Set the "not process before" timestamp to now.
    Get ComAddIntAt Of hoJsonPayload -1 "nbf" iCurDateTime To iSuccess

    // Set the timestamp defining an expiration time (end time) for the token
    // to be now + 1 hour (3600 seconds)
    Get ComAddIntAt Of hoJsonPayload -1 "exp" (iCurDateTime + 3600) To iSuccess

    Get ComUpdateString Of hoJsonPayload "iss" "me" To iSuccess
    Get ComUpdateString Of hoJsonPayload "sub" "anApiKey" To iSuccess
    Get ComUpdateString Of hoJsonPayload "aud" "https://auth-sandbox.abnamro.com/oauth/token" To iSuccess

    // Produce the smallest possible JWT:
    Set ComAutoCompact Of hoJwt To True

    Get ComEmit Of hoJsonHeader To sTemp1
    Get ComEmit Of hoJsonPayload To sTemp2
    Get ComCreateJwtPk Of hoJwt sTemp1 sTemp2 vPrivkey To sJwtStr
    Get ComLastMethodSuccess Of hoJwt To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoJwt To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Send Destroy of hoPrivkey
    Send Destroy of hoPubkey

    // Here is the JWT:
    Showln sJwtStr


End_Procedure