Read the REST Response Body in Chunks

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Demonstrates Rest.ReadRespChunkBd, which reads the response body one chunk at a time, appending each chunk to a BinData. A return value of 0 signals the body is complete, while -1 indicates a read failure.

#include <CkRest.h>
#include <CkStringBuilder.h>
#include <CkBinData.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkRest rest;
    bool bTls = true;
    bool bAutoReconnect = true;
    success = rest.Connect("example.com",443,bTls,bAutoReconnect);
    if (success == false) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    success = rest.SendReqNoBody("GET","/api/largefile");
    if (success == false) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    int statusCode = rest.ReadResponseHeader();
    if (statusCode < 0) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    //  Check for the expected success status code.  If the response is not 200, the body is likely
    //  error text formatted as JSON, XML, or HTML rather than the expected content.  In that case read
    //  the body as text, report it, and return.
    if (statusCode != 200) {
        CkStringBuilder sbError;
        success = rest.ReadRespSb(sbError);
        if (success == false) {
            std::cout << rest.lastErrorText() << "\r\n";
            return;
        }

        std::cout << "Request failed with status code " << statusCode << "\r\n";
        std::cout << sbError.getAsString() << "\r\n";
        return;
    }

    //  The status code is 200.  Read the response body in chunks, appending each chunk to the BinData.
    //  Each call waits until at least the requested number of bytes is available, unless the response
    //  ends first.  A return value of 0 means the final bytes were returned and the body is complete;
    //  -1 indicates a read failure.
    CkBinData bdBody;
    int chunkResult = rest.ReadRespChunkBd(8192,bdBody);
    while (chunkResult > 0) {
        chunkResult = rest.ReadRespChunkBd(8192,bdBody);
    }

    if (chunkResult < 0) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Received " << bdBody.get_NumBytes() << " bytes." << "\r\n";
    }