(DataFlex) Create JWT Using RSA (RS256, RS384, or RS512)

Demonstrates how to create a JWT using an RSA private key. This is for JOSE headers with an "alg" of RS256, RS384, or RS512. When RSA is used, the private key signs (creates) the JWT, and the public key is for verification.

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

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Variant vPrivKey
    Handle hoPrivKey
    Boolean iSuccess
    Handle hoJwt
    Handle hoJose
    Handle hoClaims
    Integer iCurDateTime
    String sToken
    String sTemp1
    String sTemp2

    // Demonstrates how to create a JWT using an RSA private key.

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

    Get Create (RefClass(cComChilkatPrivateKey)) To hoPrivKey
    If (Not(IsComObjectCreated(hoPrivKey))) Begin
        Send CreateComObject of hoPrivKey
    End

    // Load an RSA private key from a PEM file.
    Get ComLoadEncryptedPemFile Of hoPrivKey "qa_data/pem/rsa_passwd.pem" "passwd" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoPrivKey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatJwt)) To hoJwt
    If (Not(IsComObjectCreated(hoJwt))) Begin
        Send CreateComObject of hoJwt
    End

    // Build the JOSE header
    Get Create (RefClass(cComChilkatJsonObject)) To hoJose
    If (Not(IsComObjectCreated(hoJose))) Begin
        Send CreateComObject of hoJose
    End
    // Use RS256.  Pass the string "RS384" or "RS512" to use RSA with SHA-384 or SHA-512.
    Get ComAppendString Of hoJose "alg" "RS256" To iSuccess
    Get ComAppendString Of hoJose "typ" "JWT" To iSuccess

    // Now build the JWT claims (also known as the payload)
    Get Create (RefClass(cComChilkatJsonObject)) To hoClaims
    If (Not(IsComObjectCreated(hoClaims))) Begin
        Send CreateComObject of hoClaims
    End
    Get ComAppendString Of hoClaims "iss" "http://example.org" To iSuccess
    Get ComAppendString Of hoClaims "sub" "John" To iSuccess
    Get ComAppendString Of hoClaims "aud" "http://example.com" To iSuccess

    // Set the timestamp of when the JWT was created to now.
    Get ComGenNumericDate Of hoJwt 0 To iCurDateTime
    Get ComAddIntAt Of hoClaims -1 "iat" iCurDateTime To iSuccess

    // Set the "not process before" timestamp to now.
    Get ComAddIntAt Of hoClaims -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 hoClaims -1 "exp" (iCurDateTime + 3600) To iSuccess

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

    // Create the JWT token.  This is where the RSA signature is created.
    Get ComEmit Of hoJose To sTemp1
    Get ComEmit Of hoClaims To sTemp2
    Get pvComObject of hoPrivKey to vPrivKey
    Get ComCreateJwtPk Of hoJwt sTemp1 sTemp2 vPrivKey To sToken

    Showln sToken


End_Procedure