Sign a JWS with a Private Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPrivateKey, which sets the private key used to create a signature. The example uses RS256 (RSASSA-PKCS1-v1_5 with SHA-256).

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

IncludeFile "CkJws.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkPrivateKey.pb"

Procedure ChilkatExample()

    success.i = 0

    jws.i = CkJws::ckCreate()
    If jws.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  Protected header specifying RSASSA-PKCS1-v1_5 with SHA-256 (RS256).
    header.i = CkJsonObject::ckCreate()
    If header.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckUpdateString(header,"alg","RS256")
    success = CkJws::ckSetProtectedHeader(jws,0,header)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        ProcedureReturn
    EndIf

    bIncludeBom.i = 0
    success = CkJws::ckSetPayload(jws,"This is the content to sign.","utf-8",bIncludeBom)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        ProcedureReturn
    EndIf

    ;  The file path is relative to the application's current working directory.  An absolute path
    ;  may also be used.  Supply the path appropriate to your own environment.
    ;  Load the signer's private key and set it for signature 0.
    privKey.i = CkPrivateKey::ckCreate()
    If privKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPrivateKey::ckLoadPemFile(privKey,"qa_data/signer_privkey.pem")
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    success = CkJws::ckSetPrivateKey(jws,0,privKey)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    jwsCompact.s = CkJws::ckCreateJws(jws)
    If CkJws::ckLastMethodSuccess(jws) = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    Debug jwsCompact


    CkJws::ckDispose(jws)
    CkJsonObject::ckDispose(header)
    CkPrivateKey::ckDispose(privKey)


    ProcedureReturn
EndProcedure