(JavaScript) REST Receive Response in Chunks

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Note: This example requires Chilkat 10.1.0 or greater.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

var success = false;

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

var rest = new CkRest();

// Connect to the web server
var bTls = true;
var port = 443;
var bAutoReconnect = true;
success = rest.Connect("chilkatsoft.com",port,bTls,bAutoReconnect);
if (success == false) {
    console.log(rest.LastErrorText);
    return;
}

// Send the request.
// This can be *any* kind of request: POST, GET, PUT, etc. using *any* of the Chilkat REST methods that send requests.
// For this example, we'll just GET a simple XML document that is about 274K in size.

success = rest.SendReqNoBody("GET","/hamlet.xml");
if (success == false) {
    console.log(rest.LastErrorText);
    return;
}

// Get the response header.
var statusCode = rest.ReadResponseHeader();
if (statusCode < 0) {
    console.log(rest.LastErrorText);
    return;
}

console.log("response status code = " + statusCode);

var outputFile = "c:/temp/qa_output/hamlet.xml";

var fac = new CkFileAccess();
success = fac.OpenForWrite(outputFile);
if (statusCode < 0) {
    console.log(fac.LastErrorText);
    return;
}

// Get the response in chunks.
// (Note: There are more efficient ways to simply download a file from a web server, such as by calling Chilkat's Http.Download method.
// The purpose of this method is to show how to receive a response chunk-by-chunk.)
var bd = new CkBinData();
var status = 1;
while (status == 1) {
    // Read a minimum of 16000 bytes.
    // Note: Because of TLS message lengths, or the possibility of the response being either compressed (gzip/deflate) or in the HTTP chunked encoding,
    // the amount of data received in each call can be greater than the specified min size.
    // Chilkat will return from the call as soon as it has received an amount equal to or more than the specified size,
    // except for the very last chunk, which can be less that the min size or even 0 bytes.

    // The status will be one of three values:
    // -1 = error
    // 0 = received the last chunk of the response.
    // 1 = received a chunk, and more chunks are coming..

    // The received data is *appended* to the contents of the BinData object.
    status = rest.ReadRespChunkBd(16000,bd);
    if (status >= 0) {
        console.log("Received chunk: " + bd.NumBytes + " bytes");
        fac.FileWriteBd(bd,0,0);
        bd.Clear();
    }

}

fac.FileClose();

console.log("Success.");