Xojo Plugin

REST Receive Response in Chunks

See more REST Examples

Demonstrates how to receive a REST HTTP response in chunks.

Note: This example requires Chilkat 10.1.0 or greater.

Xojo Plugin

Dim success As Boolean
success = False

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

Dim rest As New Chilkat.Rest

// Connect to the web server
Dim bTls As Boolean
bTls = True
Dim port As Int32
port = 443
Dim bAutoReconnect As Boolean
bAutoReconnect = True
success = rest.Connect("chilkatsoft.com",port,bTls,bAutoReconnect)
If (success = False) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

// 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) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

// Get the response header.
Dim statusCode As Int32
statusCode = rest.ReadResponseHeader()
If (statusCode < 0) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

System.DebugLog("response status code = " + Str(statusCode))

Dim outputFile As String
outputFile = "c:/temp/qa_output/hamlet.xml"

Dim fac As New Chilkat.FileAccess
success = fac.OpenForWrite(outputFile)
If (statusCode < 0) Then
    System.DebugLog(fac.LastErrorText)
    Return
End If

// 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.)
Dim bd As New Chilkat.BinData
Dim status As Int32
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) Then
        System.DebugLog("Received chunk: " + Str(bd.NumBytes) + " bytes")
        success = fac.FileWriteBd(bd,0,0)
        success = bd.Clear()
    End If

Wend

fac.FileClose 

System.DebugLog("Success.")