(Lianja) S3 Complete a Multipart Upload

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>

Chilkat Lianja Extension Download Chilkat Lianja Extension

// 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.

loXmlInit = createobject("CkXml")
llSuccess = loXmlInit.LoadXmlFile("s3_multipart_uploads/initiate.xml")
if (llSuccess <> .T.) then
    ? "Did not find the initiate.xml XML file."
    release loXmlInit
    return
endif

lcUploadId = loXmlInit.GetChildContent("UploadId")
? "UploadId = " + lcUploadId

// 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.)
loXmlPartsList = createobject("CkXml")
llSuccess = loXmlPartsList.LoadXmlFile("s3_multipart_uploads/partsList.xml")
if (llSuccess <> .T.) then
    ? "Did not find the partsList.xml XML file."
    release loXmlInit
    release loXmlPartsList
    return
endif

loRest = createobject("CkRest")

// Connect to the Amazon AWS REST server.
llBTls = .T.
lnPort = 443
llBAutoReconnect = .T.
llSuccess = loRest.Connect("s3.amazonaws.com",lnPort,llBTls,llBAutoReconnect)

// ----------------------------------------------------------------------------
// 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.
loAuthAws = createobject("CkAuthAws")
loAuthAws.AccessKey = "AWS_ACCESS_KEY"
loAuthAws.SecretKey = "AWS_SECRET_KEY"
loAuthAws.ServiceName = "s3"

llSuccess = loRest.SetAuthAws(loAuthAws)

// Set the bucket name via the HOST header.
// In this case, the bucket name is "chilkat100".
loRest.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:
loRest.AddQueryParam("uploadId",lcUploadId)

// Our ObjectName in this case is "somethingBig.zip".
lcResponseXml = loRest.FullRequestString("POST","/somethingBig.zip",loXmlPartsList.GetXml())
if (loRest.LastMethodSuccess <> .T.) then
    ? loRest.LastErrorText
    release loXmlInit
    release loXmlPartsList
    release loRest
    release loAuthAws
    return
endif

// When successful, the S3 Storage service will respond with a 200 response code,
// with an XML body.  
if (loRest.ResponseStatusCode <> 200) then
    // Examine the request/response to see what happened.
    ? "response status code = " + str(loRest.ResponseStatusCode)
    ? "response status text = " + loRest.ResponseStatusText
    ? "response header: " + loRest.ResponseHeader
    ? "response body: " + lcResponseXml
    ? "---"
    ? "LastRequestStartLine: " + loRest.LastRequestStartLine
    ? "LastRequestHeader: " + loRest.LastRequestHeader
endif

// Load the XML response into Chilkat XMl and emit via GetXml to see the XML in a pretty-printed (indented) readable format.
loXml = createobject("CkXml")
loXml.LoadXml(lcResponseXml)
? loXml.GetXml()
? "----"

? "Multipart upload completed."


release loXmlInit
release loXmlPartsList
release loRest
release loAuthAws
release loXml