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.

Dim success As Long
success = 0

Dim rest As New ChilkatRest
Dim bTls As Long
bTls = 1
Dim bAutoReconnect As Long
bAutoReconnect = 1
success = rest.Connect("example.com",443,bTls,bAutoReconnect)
If (success = 0) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

success = rest.SendReqNoBody("GET","/api/largefile")
If (success = 0) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

Dim statusCode As Long
statusCode = rest.ReadResponseHeader()
If (statusCode < 0) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

'  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) Then
    Dim sbError As New ChilkatStringBuilder
    success = rest.ReadRespSb(sbError)
    If (success = 0) Then
        Debug.Print rest.LastErrorText
        Exit Sub
    End If

    Debug.Print "Request failed with status code " & statusCode
    Debug.Print sbError.GetAsString()
    Exit Sub
End If

'  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.
Dim bdBody As New ChilkatBinData
Dim chunkResult As Long
chunkResult = rest.ReadRespChunkBd(8192,bdBody)
Do While chunkResult > 0
    chunkResult = rest.ReadRespChunkBd(8192,bdBody)
Loop
If (chunkResult < 0) Then
    Debug.Print rest.LastErrorText
    Exit Sub
End If

Debug.Print "Received " & bdBody.NumBytes & " bytes."