(Go) Sign JSON to Create CAdES P7S Bytes

Demonstrates how to sign JSON using a certificate + private key from a .p12/.pfx to create a CAdES P7S byte array.

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

    crypt := chilkat.NewCrypt2()

    cert := chilkat.NewCert()
    success := cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
    if success != true {
        fmt.Println(cert.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        return
    }

    // Tell the crypt component to use this cert.
    success = crypt.SetSigningCert(cert)
    if success != true {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        return
    }

    // The CadesEnabled property applies to all methods that create PKCS7 signatures. 
    // To create a CAdES-BES signature, set this property equal to true. 
    crypt.SetCadesEnabled(true)

    crypt.SetHashAlgorithm("sha256")

    jsonSigningAttrs := chilkat.NewJsonObject()
    jsonSigningAttrs.UpdateInt("contentType",1)
    jsonSigningAttrs.UpdateInt("signingTime",1)
    jsonSigningAttrs.UpdateInt("messageDigest",1)
    jsonSigningAttrs.UpdateInt("signingCertificateV2",1)
    crypt.SetSigningAttributes(jsonSigningAttrs.Emit())

    // By default, all the certs in the chain of authentication are included in the signature.
    // If desired, we can choose to only include the signing certificate:
    crypt.SetIncludeCertChain(false)

    // Create the CAdES-BES attached signature, which contains the original data.
    crypt.SetCharset("utf-8")

    cadesP7s = crypt.OpaqueSignString("{ \"abc\": 123}")
    if crypt.LastMethodSuccess() == false {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        jsonSigningAttrs.DisposeJsonObject()
        return
    }

    // Verify the signature and extract the original JSON:
    originalJson := crypt.OpaqueVerifyString(cadesP7s)
    if crypt.LastMethodSuccess() == false {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        jsonSigningAttrs.DisposeJsonObject()
        return
    }

    fmt.Println("Original JSON: ", *originalJson)

    fmt.Println("Success!")

    crypt.DisposeCrypt2()
    cert.DisposeCert()
    jsonSigningAttrs.DisposeJsonObject()