(C++) Streaming Decrypt HTTP Response

If the an encrypted file was previously uploaded, this example demonstrates how to download and decrypt in a streaming way.

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#include <CkRest.h>
#include <CkCrypt2.h>
#include <CkStream.h>
#include <CkTask.h>

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

    CkRest rest;

    bool bTls = true;
    int port = 443;
    bool bAutoReconnect = true;
    bool success = rest.Connect("chilkatdownload.com",port,bTls,bAutoReconnect);

    // Send the request to download a file.
    success = rest.SendReqNoBody("GET","/9.5.0.83/chilkat-9.5.0-python-3.8-x64.zip");
    if (success != true) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    // Read the response header.
    int responseStatusCode = rest.ReadResponseHeader();
    if (responseStatusCode < 0) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Response status code = " << responseStatusCode << "\r\n";

    // We expect a 200 response status if the JPG data is coming.
    // Otherwise, we'll get a string response body with an error message(or no response body).
    if (responseStatusCode != 200) {
        const char *errResponse = rest.readRespBodyString();
        if (rest.get_LastMethodSuccess() != true) {
            std::cout << rest.lastErrorText() << "\r\n";
        }
        else {
            std::cout << errResponse << "\r\n";
        }

        return;
    }

    // Create an object for decrypting.
    // This example will use "none" for the encryption algorithm, which means it's just a pass-through.
    // Typically you would set the decrypt properties, such as secret key, IV, key length, padding scheme, cipher mode..
    CkCrypt2 crypt;
    crypt.put_CryptAlgorithm("none");

    // The following settings are ignored in this test because our CryptAlgorithm is "none".
    // However, if you were truly decrypting, you might set CryptAlgorithm = "aes".
    crypt.put_CipherMode("cbc");
    crypt.put_KeyLength(128);
    crypt.SetEncodedKey("000102030405060708090A0B0C0D0E0F","hex");
    crypt.SetEncodedIV("000102030405060708090A0B0C0D0E0F","hex");

    CkStream receiveStream;
    // The decryptStream's source will be the receiveStream.
    CkStream decryptStream;

    // The decrypt stream's sink will be a file.
    decryptStream.put_SinkFile("qa_output/chilkat-9.5.0-python-3.8-x64.zip");
    decryptStream.SetSourceStream(receiveStream);

    // Create and run a background async task to decrypt incoming data and write to a file.
    CkTask *decryptStreamTask = crypt.DecryptStreamAsync(decryptStream);
    success = decryptStreamTask->Run();

    success = rest.ReadRespBodyStream(receiveStream,true);
    if (success != true) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Successfully received the .zip file." << "\r\n";
    }