Objective-C
Objective-C
S3 Upload the Parts for a Multipart Upload
See more Amazon S3 (new) Examples
This example uploads a large file in parts. The multipart upload needs to have been first initiated prior to uploading the parts.See http://docs.aws.amazon.com/AmazonS3/latest/API/mpUploadUploadPart.html for more information about uploading parts.
Chilkat Objective-C Downloads
#import <CkoXml.h>
#import <NSString.h>
#import <CkoFileAccess.h>
#import <CkoRest.h>
#import <CkoAuthAws.h>
#import <CkoStringBuilder.h>
#import <CkoStream.h>
BOOL success = NO;
// In the 1st step for uploading a large file, the multipart upload was initiated
// as shown here: Initiate Multipart Upload
// Other S3 Multipart Upload Examples:
// Complete Multipart Upload
// Abort Multipart Upload
// List Parts
// When we initiated the multipart upload, we saved the XML response to a file. This
// XML response contains the UploadId. We'll begin by loading that XML and getting
// the Upload ID.
CkoXml *xmlInit = [[CkoXml alloc] init];
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);
// When uploading parts, we need to keep an XML record of each part number
// and its corresponding ETag, which is received in the response for each part.
// There can be up to 10000 parts, numbered 1 to 10000.
// After all parts have been uploaded, the final step will be to complete
// the multipart upload (see Complete Multipart Upload)
// In this example, the large file we want to upload is somethingBig.zip
NSString *fileToUploadPath = @"s3_multipart_uploads/somethingBig.zip";
// The minimum allowed part size is 5MB (5242880 bytes). The last part can be smaller because
// it will contain the remainder of the file. (This minimum is enforced by the AWS service.)
// We'll use the minimum allowed part size for this example.
int partSize = 5242880;
// Let's use Chilkat's FileAccess API to examine the file to be uploaded. We'll get the size
// of the file and find out how many parts will be needed, including the final "partial" part.
CkoFileAccess *fac = [[CkoFileAccess alloc] init];
[fac OpenForRead: fileToUploadPath];
// How many parts will there be if each part is 5242880 bytes?
int numParts = [[fac GetNumBlocks: [NSNumber numberWithInt: partSize]] intValue];
NSLog(@"%@%d",@"numParts = ",numParts);
[fac FileClose];
// Imagine that we may be running this for the 1st time, or maybe we already
// attempted to upload parts, and something failed. Maybe there was a network problem
// the resulted in not all parts getting uploaded. We'll write this code so that if run again,
// it will upload whatever parts haven't yet been uploaded.
// We'll keep a partsList.xml file to record the parts that have already been successfully
// uploaded. If this file does not yet exist, we'll create it..
NSString *partsListFile = @"s3_multipart_uploads/partsList.xml";
CkoXml *partsListXml = [[CkoXml alloc] init];
if ([fac FileExists: partsListFile] == YES) {
[partsListXml LoadXmlFile: partsListFile];
}
// Make sure the top-level tag is "CompleteMultipartUpload"
partsListXml.Tag = @"CompleteMultipartUpload";
// --------------------------------------
// Before entering the loop to upload parts,
// setup the REST object with AWS authentication,
// and make the initial connection.
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";
// --------------------------------------
int partNumber = 1;
CkoStringBuilder *sbPartNumber = [[CkoStringBuilder alloc] init];
while ((partNumber <= numParts)) {
NSLog(@"%@%d%@",@"---- ",partNumber,@" ----");
// This cumbersome way of converting an integer to a string is because
// Chilkat examples are written in a script that is converted to many programming languages.
// At this time, the translator does not have integer-to-string code generation capability..
[sbPartNumber Clear];
[sbPartNumber AppendInt: [NSNumber numberWithInt: partNumber]];
BOOL bPartAlreadyUploaded = NO;
// If there are no children, then the XML is empty and no parts have yet been uploaded.
int numUploadedParts = [partsListXml.NumChildren intValue];
if (numUploadedParts > 0) {
// If some parts have been uploaded, check to see if this particular part was already upload.
// If so, then it can be skipped.
// Position ourselves at the 1st record.
CkoXml *xRec0 = [partsListXml GetChild: [NSNumber numberWithInt: 0]];
CkoXml *foundRec = [xRec0 FindNextRecord: @"PartNumber" contentPattern: [sbPartNumber GetAsString]];
if (xRec0.LastMethodSuccess == YES) {
bPartAlreadyUploaded = YES;
NSLog(@"%@%d%@",@"Part ",partNumber,@" was previously uploaded.");
NSLog(@"%@",[foundRec GetXml]);
}
}
// If this part was not already uploaded, we need to upload.
// Also update the partsListXml and save as each part is successfully uploaded.
if (bPartAlreadyUploaded == NO) {
NSLog(@"%@%d%@",@"Uploading part ",partNumber,@" ...");
// Setup the stream source for the large file to be uploaded..
CkoStream *fileStream = [[CkoStream alloc] init];
fileStream.SourceFile = fileToUploadPath;
// The Chilkat Stream API has features to make uploading a parts
// of a file easy. Indicate the part size by setting the SourceFilePartSize
// property.
fileStream.SourceFilePartSize = [NSNumber numberWithInt: partSize];
// Our HTTP start line to upload a part will look like this:
// PUT /ObjectName?partNumber=PartNumber&uploadId=UploadId HTTP/1.1
// Set the query params. We'll need partNumber and uploadId.
// Make sure the query params from previous iterations are clear.
[rest ClearAllQueryParams];
[rest AddQueryParam: @"partNumber" value: [sbPartNumber GetAsString]];
[rest AddQueryParam: @"uploadId" value: uploadId];
// Upload this particular file part.
// Tell the fileStream which part is being uploaded.
// Our partNumber is 1-based (the 1st part is at index 1), but the fileStream's SourceFilePart
// property is 0-based. Therefore we use partNumber-1.
fileStream.SourceFilePart = [NSNumber numberWithInt: (partNumber - 1)];
// Because the SourceFilePart and SourceFilePartSize properties are set, the stream will
// will provide just that part of the file.
NSString *responseStr = [rest FullRequestStream: @"PUT" uriPath: @"/somethingBig.zip" stream: fileStream];
if (rest.LastMethodSuccess != YES) {
NSLog(@"%@",rest.LastErrorText);
return;
}
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: ",responseStr);
NSLog(@"%@",@"---");
NSLog(@"%@%@",@"LastRequestStartLine: ",rest.LastRequestStartLine);
NSLog(@"%@%@",@"LastRequestHeader: ",rest.LastRequestHeader);
return;
}
// OK, this part was uploaded..
// The response will have a 0-length body. The only information we need is the
// ETag response header field.
NSString *etag = [rest ResponseHdrByName: @"ETag"];
// It should be present, but just in case there was no ETag header...
if (rest.LastMethodSuccess != YES) {
NSLog(@"%@",@"No ETag response header found!");
NSLog(@"%@%@",@"response header: ",rest.ResponseHeader);
return;
}
// We need to add record to the partsListXml.
// The record will look like this:
// <Part>
// <PartNumber>PartNumber</PartNumber>
// <ETag>ETag</ETag>
// </Part>
CkoXml *xPart = [partsListXml NewChild: @"Part" content: @""];
[xPart NewChildInt2: @"PartNumber" value: [NSNumber numberWithInt: partNumber]];
[xPart NewChild2: @"ETag" content: etag];
success = [partsListXml SaveXml: partsListFile];
if (success != YES) {
NSLog(@"%@",partsListXml.LastErrorText);
return;
}
NSLog(@"%@%d%@",@"-- Part ",partNumber,@" uploaded. ---------------------");
}
partNumber = partNumber + 1;
}
NSLog(@"%@",@"Finished. All parts uploaded.");