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.

    success := false

    rest := chilkat.NewRest()
    bTls := true
    bAutoReconnect := true
    success = rest.Connect("example.com",443,bTls,bAutoReconnect)
    if success == false {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    success = rest.SendReqNoBody("GET","/api/largefile")
    if success == false {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    statusCode := rest.ReadResponseHeader()
    if statusCode < 0 {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        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 {
        sbError := chilkat.NewStringBuilder()
        success = rest.ReadRespSb(sbError)
        if success == false {
            fmt.Println(rest.LastErrorText())
            rest.DisposeRest()
            sbError.DisposeStringBuilder()
            return
        }

        fmt.Println("Request failed with status code ", statusCode)
        fmt.Println(*sbError.GetAsString())
        rest.DisposeRest()
        sbError.DisposeStringBuilder()
        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.
    bdBody := chilkat.NewBinData()
    chunkResult := rest.ReadRespChunkBd(8192,bdBody)
    for chunkResult > 0 {
        chunkResult = rest.ReadRespChunkBd(8192,bdBody)
    }

    if chunkResult < 0 {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        sbError.DisposeStringBuilder()
        bdBody.DisposeBinData()
        return
    }

    fmt.Println("Received ", bdBody.NumBytes(), " bytes.")

    rest.DisposeRest()
    sbError.DisposeStringBuilder()
    bdBody.DisposeBinData()