(Unicode C) S3 Upload the Parts for a Multipart Upload

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.

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#include <C_CkXmlW.h>
#include <C_CkFileAccessW.h>
#include <C_CkRestW.h>
#include <C_CkAuthAwsW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkStreamW.h>

void ChilkatSample(void)
    {
    HCkXmlW xmlInit;
    BOOL success;
    const wchar_t *uploadId;
    const wchar_t *fileToUploadPath;
    int partSize;
    HCkFileAccessW fac;
    int numParts;
    const wchar_t *partsListFile;
    HCkXmlW partsListXml;
    HCkRestW rest;
    BOOL bTls;
    int port;
    BOOL bAutoReconnect;
    HCkAuthAwsW authAws;
    int partNumber;
    HCkStringBuilderW sbPartNumber;
    BOOL bPartAlreadyUploaded;
    int numUploadedParts;
    HCkXmlW xRec0;
    HCkXmlW foundRec;
    HCkStreamW fileStream;
    const wchar_t *responseStr;
    const wchar_t *etag;
    HCkXmlW xPart;

    // 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.

    xmlInit = CkXmlW_Create();
    success = CkXmlW_LoadXmlFile(xmlInit,L"s3_multipart_uploads/initiate.xml");
    if (success != TRUE) {
        wprintf(L"Did not find the initiate.xml XML file.\n");
        CkXmlW_Dispose(xmlInit);
        return;
    }

    uploadId = CkXmlW_getChildContent(xmlInit,L"UploadId");
    wprintf(L"UploadId = %s\n",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
    fileToUploadPath = L"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.
    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.
    fac = CkFileAccessW_Create();
    CkFileAccessW_OpenForRead(fac,fileToUploadPath);

    // How many parts will there be if each part is 5242880 bytes?
    numParts = CkFileAccessW_GetNumBlocks(fac,partSize);
    wprintf(L"numParts = %d\n",numParts);
    CkFileAccessW_FileClose(fac);

    // 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..
    partsListFile = L"s3_multipart_uploads/partsList.xml";
    partsListXml = CkXmlW_Create();
    if (CkFileAccessW_FileExists(fac,partsListFile) == TRUE) {
        CkXmlW_LoadXmlFile(partsListXml,partsListFile);
    }

    // Make sure the top-level tag is "CompleteMultipartUpload"
    CkXmlW_putTag(partsListXml,L"CompleteMultipartUpload");

    // --------------------------------------
    // Before entering the loop to upload parts,
    // setup the REST object with AWS authentication,
    // and make the initial connection.
    rest = CkRestW_Create();

    // Connect to the Amazon AWS REST server.
    bTls = TRUE;
    port = 443;
    bAutoReconnect = TRUE;
    success = CkRestW_Connect(rest,L"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.
    authAws = CkAuthAwsW_Create();
    CkAuthAwsW_putAccessKey(authAws,L"AWS_ACCESS_KEY");
    CkAuthAwsW_putSecretKey(authAws,L"AWS_SECRET_KEY");
    CkAuthAwsW_putServiceName(authAws,L"s3");
    success = CkRestW_SetAuthAws(rest,authAws);

    // Set the bucket name via the HOST header.
    // In this case, the bucket name is "chilkat100".
    CkRestW_putHost(rest,L"chilkat100.s3.amazonaws.com");
    // --------------------------------------

    partNumber = 1;
    sbPartNumber = CkStringBuilderW_Create();

    while ((partNumber <= numParts)) {
        wprintf(L"---- %d ----\n",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..
        CkStringBuilderW_Clear(sbPartNumber);
        CkStringBuilderW_AppendInt(sbPartNumber,partNumber);

        bPartAlreadyUploaded = FALSE;

        // If there are no children, then the XML is empty and no parts have yet been uploaded.
        numUploadedParts = CkXmlW_getNumChildren(partsListXml);
        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.
            xRec0 = CkXmlW_GetChild(partsListXml,0);
            foundRec = CkXmlW_FindNextRecord(xRec0,L"PartNumber",CkStringBuilderW_getAsString(sbPartNumber));
            if (CkXmlW_getLastMethodSuccess(xRec0) == TRUE) {
                bPartAlreadyUploaded = TRUE;
                wprintf(L"Part %d was previously uploaded.\n",partNumber);
                wprintf(L"%s\n",CkXmlW_getXml(foundRec));
                CkXmlW_Dispose(foundRec);
            }

            CkXmlW_Dispose(xRec0);
        }

        // 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 == FALSE) {
            wprintf(L"Uploading part %d ...\n",partNumber);

            // Setup the stream source for the large file to be uploaded..
            fileStream = CkStreamW_Create();
            CkStreamW_putSourceFile(fileStream,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.
            CkStreamW_putSourceFilePartSize(fileStream,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.
            CkRestW_ClearAllQueryParams(rest);
            CkRestW_AddQueryParam(rest,L"partNumber",CkStringBuilderW_getAsString(sbPartNumber));
            CkRestW_AddQueryParam(rest,L"uploadId",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.
            CkStreamW_putSourceFilePart(fileStream,partNumber - 1);

            // Because the SourceFilePart and SourceFilePartSize properties are set, the stream will 
            // will provide just that part of the file.  
            responseStr = CkRestW_fullRequestStream(rest,L"PUT",L"/somethingBig.zip",fileStream);
            if (CkRestW_getLastMethodSuccess(rest) != TRUE) {
                wprintf(L"%s\n",CkRestW_lastErrorText(rest));
                CkXmlW_Dispose(xmlInit);
                CkFileAccessW_Dispose(fac);
                CkXmlW_Dispose(partsListXml);
                CkRestW_Dispose(rest);
                CkAuthAwsW_Dispose(authAws);
                CkStringBuilderW_Dispose(sbPartNumber);
                CkStreamW_Dispose(fileStream);
                return;
            }

            if (CkRestW_getResponseStatusCode(rest) != 200) {
                // Examine the request/response to see what happened.
                wprintf(L"response status code = %d\n",CkRestW_getResponseStatusCode(rest));
                wprintf(L"response status text = %s\n",CkRestW_responseStatusText(rest));
                wprintf(L"response header: %s\n",CkRestW_responseHeader(rest));
                wprintf(L"response body: %s\n",responseStr);
                wprintf(L"---\n");
                wprintf(L"LastRequestStartLine: %s\n",CkRestW_lastRequestStartLine(rest));
                wprintf(L"LastRequestHeader: %s\n",CkRestW_lastRequestHeader(rest));
                CkXmlW_Dispose(xmlInit);
                CkFileAccessW_Dispose(fac);
                CkXmlW_Dispose(partsListXml);
                CkRestW_Dispose(rest);
                CkAuthAwsW_Dispose(authAws);
                CkStringBuilderW_Dispose(sbPartNumber);
                CkStreamW_Dispose(fileStream);
                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.
            etag = CkRestW_responseHdrByName(rest,L"ETag");
            // It should be present, but just in case there was no ETag header...
            if (CkRestW_getLastMethodSuccess(rest) != TRUE) {
                wprintf(L"No ETag response header found!\n");
                wprintf(L"response header: %s\n",CkRestW_responseHeader(rest));
                CkXmlW_Dispose(xmlInit);
                CkFileAccessW_Dispose(fac);
                CkXmlW_Dispose(partsListXml);
                CkRestW_Dispose(rest);
                CkAuthAwsW_Dispose(authAws);
                CkStringBuilderW_Dispose(sbPartNumber);
                CkStreamW_Dispose(fileStream);
                return;
            }

            // We need to add record to the partsListXml.
            // The record will look like this:
            // &lt;Part>
            //   &lt;PartNumber>PartNumber&lt;/PartNumber>
            //   &lt;ETag>ETag&lt;/ETag>
            // &lt;/Part>
            xPart = CkXmlW_NewChild(partsListXml,L"Part",L"");
            CkXmlW_NewChildInt2(xPart,L"PartNumber",partNumber);
            CkXmlW_NewChild2(xPart,L"ETag",etag);
            CkXmlW_Dispose(xPart);

            success = CkXmlW_SaveXml(partsListXml,partsListFile);
            if (success != TRUE) {
                wprintf(L"%s\n",CkXmlW_lastErrorText(partsListXml));
                CkXmlW_Dispose(xmlInit);
                CkFileAccessW_Dispose(fac);
                CkXmlW_Dispose(partsListXml);
                CkRestW_Dispose(rest);
                CkAuthAwsW_Dispose(authAws);
                CkStringBuilderW_Dispose(sbPartNumber);
                CkStreamW_Dispose(fileStream);
                return;
            }

            wprintf(L"-- Part %d uploaded. ---------------------\n",partNumber);
        }

        partNumber = partNumber + 1;
    }

    wprintf(L"Finished.  All parts uploaded.\n");


    CkXmlW_Dispose(xmlInit);
    CkFileAccessW_Dispose(fac);
    CkXmlW_Dispose(partsListXml);
    CkRestW_Dispose(rest);
    CkAuthAwsW_Dispose(authAws);
    CkStringBuilderW_Dispose(sbPartNumber);
    CkStreamW_Dispose(fileStream);

    }