(AutoIt) AWS S3 File Streaming Upload

Demonstrates how to do a streaming upload from a file to the AWS S3 storage service. The AWS authorization presents some difficulties when the REST request body is to be streamed from a file (or from some other source). The issue is that the SHA-256 hash of the file data must be calculated. There are only two possible ways to do this: (1) stream the file into memory in its entirety and calculate the SHA-256 hash prior to uploading, or (2) pre-calculate the SHA-256 in a streaming fashion, and then provide it to the AWS authentication object.

If the application does NOT pre-compute the SHA-256, then Chilkat (internally) is forced to stream into memory, calculate the SHA-256, and then upload from the in-memory copy of the file.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

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

; This first part is optional.  AWS authentication requires
; the SHA-256 hash of the request body (i.e. the contents of the file
; to be uploaded).  We can choose to pre-calculate the SHA-256 in a streaming fashion
; and then provide it to the authenticator object.  This way, if the file is
; extremely large, it never needs to completely reside in memory.
$oCrypt = ObjCreate("Chilkat.Crypt2")
$oCrypt.EncodingMode = "hex"
$oCrypt.HashAlgorithm = "sha-256"
Local $sFileToUploadPath = "qa_data/xml/hamlet.xml"
Local $sHashStr = $oCrypt.HashFileENC($sFileToUploadPath)

$oRest = ObjCreate("Chilkat.Rest")

; Connect to the Amazon AWS REST server.
Local $bTls = True
Local $iPort = 443
Local $bAutoReconnect = True
Local $bSuccess = $oRest.Connect("s3.amazonaws.com",$iPort,$bTls,$bAutoReconnect)

; ----------------------------------------------------------------------------
; Important: For buckets created in regions outside us-east-1,
; there are three important changes that need to be made.
; See Working with S3 Buckets in Non-us-east-1 Regions for the details.
; ----------------------------------------------------------------------------

; Provide AWS credentials for the REST call.
$oAuthAws = ObjCreate("Chilkat.AuthAws")
$oAuthAws.AccessKey = "AWS_ACCESS_KEY"
$oAuthAws.SecretKey = "AWS_SECRET_KEY"
$oAuthAws.ServiceName = "s3"
; Provide the pre-computed SHA-256 here:
$oAuthAws.PrecomputedSha256 = $sHashStr

$bSuccess = $oRest.SetAuthAws($oAuthAws)

; Set the bucket name via the HOST header.
; In this case, the bucket name is "chilkat100".
$oRest.Host = "chilkat100.s3.amazonaws.com"

$oFileStream = ObjCreate("Chilkat.Stream")
$oFileStream.SourceFile = $sFileToUploadPath

; Upload to the S3 Storage service.
; If the application provided the SHA-256 hash of the file contents (as shown above)
; then file is streamed and never has to completely reside in memory.
; If the application did NOT provide the SHA-256, then Chilkat will (internally) 
; load the entire file into memory, calculate the SHA-256, and then upload.
Local $sResponseStr = $oRest.FullRequestStream("PUT","/hamlet.xml",$oFileStream)
If ($oRest.LastMethodSuccess <> True) Then
    ConsoleWrite($oRest.LastErrorText & @CRLF)
    Exit
EndIf

; When successful, the S3 Storage service will respond with a 200 response code,
; with an XML body.  
If ($oRest.ResponseStatusCode = 200) Then
    ConsoleWrite($sResponseStr & @CRLF)
    ConsoleWrite("File uploaded." & @CRLF)
Else
    ; Examine the request/response to see what happened.
    ConsoleWrite("response status code = " & $oRest.ResponseStatusCode & @CRLF)
    ConsoleWrite("response status text = " & $oRest.ResponseStatusText & @CRLF)
    ConsoleWrite("response header: " & $oRest.ResponseHeader & @CRLF)
    ConsoleWrite("response body: " & $sResponseStr & @CRLF)
    ConsoleWrite("---" & @CRLF)
    ConsoleWrite("LastRequestStartLine: " & $oRest.LastRequestStartLine & @CRLF)
    ConsoleWrite("LastRequestHeader: " & $oRest.LastRequestHeader & @CRLF)
EndIf