(Objective-C) 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 Objective-C Library Downloads MAC OS X (Cocoa) Libs iOS Libs

#import <CkoXml.h>
#import <NSString.h>
#import <CkoRest.h>
#import <CkoAuthAws.h>

// 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.

CkoXml *xmlInit = [[CkoXml alloc] init];
BOOL success = [xmlInit LoadXmlFile: @"s3_multipart_uploads/initiate.xml"];
if (success != YES) {
    NSLog(@"%@",@"Did not find the initiate.xml XML file.");
    return;
}

NSString *uploadId = [xmlInit GetChildContent: @"UploadId"];
NSLog(@"%@%@",@"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.)
CkoXml *xmlPartsList = [[CkoXml alloc] init];
success = [xmlPartsList LoadXmlFile: @"s3_multipart_uploads/partsList.xml"];
if (success != YES) {
    NSLog(@"%@",@"Did not find the partsList.xml XML file.");
    return;
}

CkoRest *rest = [[CkoRest alloc] init];

// Connect to the Amazon AWS REST server.
BOOL bTls = YES;
int port = 443;
BOOL bAutoReconnect = YES;
success = [rest Connect: @"s3.amazonaws.com" port: [NSNumber numberWithInt: port] tls: bTls autoReconnect: 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.
CkoAuthAws *authAws = [[CkoAuthAws alloc] init];
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:
[rest AddQueryParam: @"uploadId" value: uploadId];

// Our ObjectName in this case is "somethingBig.zip".
NSString *responseXml = [rest FullRequestString: @"POST" uriPath: @"/somethingBig.zip" bodyText: [xmlPartsList GetXml]];
if (rest.LastMethodSuccess != YES) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

// When successful, the S3 Storage service will respond with a 200 response code,
// with an XML body.  
if ([rest.ResponseStatusCode intValue] != 200) {
    // Examine the request/response to see what happened.
    NSLog(@"%@%d",@"response status code = ",[rest.ResponseStatusCode intValue]);
    NSLog(@"%@%@",@"response status text = ",rest.ResponseStatusText);
    NSLog(@"%@%@",@"response header: ",rest.ResponseHeader);
    NSLog(@"%@%@",@"response body: ",responseXml);
    NSLog(@"%@",@"---");
    NSLog(@"%@%@",@"LastRequestStartLine: ",rest.LastRequestStartLine);
    NSLog(@"%@%@",@"LastRequestHeader: ",rest.LastRequestHeader);
}

// Load the XML response into Chilkat XMl and emit via GetXml to see the XML in a pretty-printed (indented) readable format.
CkoXml *xml = [[CkoXml alloc] init];
[xml LoadXml: responseXml];
NSLog(@"%@",[xml GetXml]);
NSLog(@"%@",@"----");

NSLog(@"%@",@"Multipart upload completed.");