Xojo Plugin

S3 Complete a Multipart Upload

See more Amazon S3 (new) Examples

This operation completes a multipart upload by assembling previously uploaded parts.

Processing of a Complete Multipart Upload request could take several minutes to complete. After Amazon S3 begins processing the request, it sends an HTTP response header that specifies a 200 OK response. While processing is in progress, Amazon S3 periodically sends whitespace characters to keep the connection from timing out. Because a request could fail after the initial 200 OK response has been sent, it is important that you check the response body to determine whether the request succeeded.

This example sends a POST request to complete a multipart upload, which looks like this:

POST /ObjectName?uploadId=UploadId HTTP/1.1
Host: BucketName.s3.amazonaws.com
Date: Date
Content-Length: Size
Authorization: authorization string

<CompleteMultipartUpload>
  <Part>
    <PartNumber>PartNumber</PartNumber>
    <ETag>ETag</ETag>
  </Part>
  ...
</CompleteMultipartUpload>

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.

// The 1st step in an S3 multipart upload is to initiate it,
// as shown here: Initiate S3 Multipart Upload

// The 2nd step is to upload the parts
// as shown here: S3 Upload Parts

// The 3rd and final step (this example) is to complete the multipart upload.

// Other S3 Multipart Upload Examples:
// Abort Multipart Upload
// List Parts

// When the multipart upload was initiated, an UploadId was provided in the XML response, and it 
// was saved to a file.  Steps 2 and 3 begin by loading the XML and getting
// the Upload ID.

Dim xmlInit As New Chilkat.Xml
success = xmlInit.LoadXmlFile("s3_multipart_uploads/initiate.xml")
If (success <> True) Then
    System.DebugLog("Did not find the initiate.xml XML file.")
    Return
End If

Dim uploadId As String
uploadId = xmlInit.GetChildContent("UploadId")
System.DebugLog("UploadId = " + uploadId)

// We'll also need the XML file that contains a record of the parts
// with part numbers and ETags.  (This file was produced when parts were being uploaded.)
Dim xmlPartsList As New Chilkat.Xml
success = xmlPartsList.LoadXmlFile("s3_multipart_uploads/partsList.xml")
If (success <> True) Then
    System.DebugLog("Did not find the partsList.xml XML file.")
    Return
End If

Dim rest As New Chilkat.Rest

// Connect to the Amazon AWS REST server.
Dim bTls As Boolean
bTls = True
Dim port As Int32
port = 443
Dim bAutoReconnect As Boolean
bAutoReconnect = True
success = rest.Connect("s3.amazonaws.com",port,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.
Dim authAws As New Chilkat.AuthAws
authAws.AccessKey = "AWS_ACCESS_KEY"
authAws.SecretKey = "AWS_SECRET_KEY"
authAws.ServiceName = "s3"

success = rest.SetAuthAws(authAws)

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

// The "uploadId=UploadId" must be added as a query parameter.  This allows it to be 
// incorporated into the AWS signature calculation, which is a requirement.
// Therefore, we use AddQueryParam:
success = rest.AddQueryParam("uploadId",uploadId)

// Our ObjectName in this case is "somethingBig.zip".
Dim responseXml As String
responseXml = rest.FullRequestString("POST","/somethingBig.zip",xmlPartsList.GetXml())
If (rest.LastMethodSuccess <> True) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

// When successful, the S3 Storage service will respond with a 200 response code,
// with an XML body.  
If (rest.ResponseStatusCode <> 200) Then
    // Examine the request/response to see what happened.
    System.DebugLog("response status code = " + Str(rest.ResponseStatusCode))
    System.DebugLog("response status text = " + rest.ResponseStatusText)
    System.DebugLog("response header: " + rest.ResponseHeader)
    System.DebugLog("response body: " + responseXml)
    System.DebugLog("---")
    System.DebugLog("LastRequestStartLine: " + rest.LastRequestStartLine)
    System.DebugLog("LastRequestHeader: " + rest.LastRequestHeader)
End If

// Load the XML response into Chilkat XMl and emit via GetXml to see the XML in a pretty-printed (indented) readable format.
Dim xml As New Chilkat.Xml
success = xml.LoadXml(responseXml)
System.DebugLog(xml.GetXml())
System.DebugLog("----")

System.DebugLog("Multipart upload completed.")