(Unicode C++) Upload File in Blocks (with Content-MD5 header) and Commit the Block List

Demonstrates how to upload a file in blocks and then commit the block list. This example includes a Content-MD5 header for each block.

Chilkat C/C++ Library Downloads
MS Visual C/C++ Linux/CentOS C/C++ Alpine Linux C/C++ MAC OS X C/C++	armhf/aarch64 C/C++ C++ Builder iOS C/C++ Android C/C++	Solaris C/C++ MinGW C/C++

#include <CkRestW.h>
#include <CkAuthAzureStorageW.h>
#include <CkXmlW.h>
#include <CkFileAccessW.h>
#include <CkCrypt2W.h>
#include <CkStringBuilderW.h>
#include <CkBinDataW.h>

void ChilkatSample(void)
    {
    // Azure Blob Service Example: Upload a file in blocks, and then commit the block list.
    // See also: https://msdn.microsoft.com/en-us/library/azure/dd135726.aspx

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkRestW rest;

    // Connect to the Azure Storage Blob Service
    bool bTls = true;
    int port = 443;
    bool bAutoReconnect = true;
    // In this example, the storage account name is "chilkat".
    bool success = rest.Connect(L"chilkat.blob.core.windows.net",port,bTls,bAutoReconnect);
    if (success != true) {
        wprintf(L"%s\n",rest.lastErrorText());
        return;
    }

    // Provide Azure Cloud credentials for the REST call.
    CkAuthAzureStorageW azAuth;
    azAuth.put_AccessKey(L"AZURE_ACCESS_KEY");
    // The account name used here should match the 1st part of the domain passed in the call to Connect (above).
    azAuth.put_Account(L"chilkat");
    azAuth.put_Scheme(L"SharedKey");
    azAuth.put_Service(L"Blob");
    // This causes the "x-ms-version: 2020-08-04" header to be automatically added.
    azAuth.put_XMsVersion(L"2020-08-04");
    success = rest.SetAuthAzureStorage(azAuth);

    // Note: The application does not need to explicitly set the following
    // headers: Content-Length, x-ms-date, Authorization.  These headers
    // are automatically set by Chilkat.

    // As the blocks are uploaded, we'll keep an XML block list for the subsequent commit..
    CkXmlW xml;
    xml.put_Tag(L"BlockList");

    // Any type of file can be uploaded in this way.  It can a text file, binary file, anything...
    // This example will upload an XML file that is approximately 275K in size.  It can be downloaded
    // at http://www.chilkatsoft.com/hamlet.xml
    CkFileAccessW fac;
    success = fac.OpenForRead(L"qa_data/xml/hamlet.xml");
    // Assuming success for the example..

    // We'll upload in 16K blocks (normally a program would upload in larger block sizes than this,
    // but this is just an example...)
    int blockSize = 16384;

    // How many 16K blocks?  (Including 1 for the last partial block)
    int numBlocks = fac.GetNumBlocks(blockSize);

    CkCrypt2W crypt;
    crypt.put_HashAlgorithm(L"md5");

    CkStringBuilderW sbResponseBody;
    CkStringBuilderW uriPath;
    const wchar_t *blockId = 0;
    CkBinDataW dataBlock;
    const wchar_t *contentMd5 = 0;
    int i = 0;
    while (i < numBlocks) {

        dataBlock.Clear();
        success = fac.ReadBlockBd(i,blockSize,dataBlock);
        if (success == false) {
            wprintf(L"%s\n",fac.lastErrorText());
            return;
        }

        // Generate a base64 block ID.  
        // (Chilkat provides a helper method named GenBlockId to make this easy)
        // A pre-base64 encoded block ID length of 4 is sufficient in this case because
        // this file certainly won't have more than 99,999 blocks..
        blockId = fac.genBlockId(i,4,L"base64");

        // Add this blockId to the list of blocks to be committed.
        xml.NewChild2(L"Latest",blockId);

        // Build the URI path
        uriPath.Clear();
        success = uriPath.Append(L"/mycontainer/hamlet.xml?comp=block&blockId=");
        success = uriPath.Append(blockId);

        contentMd5 = crypt.hashBdENC(dataBlock);
        rest.AddHeader(L"Content-MD5",contentMd5);

        // Upload this block..
        sbResponseBody.Clear();
        success = rest.FullRequestBd(L"PUT",uriPath.getAsString(),dataBlock,sbResponseBody);
        if (success == false) {
            wprintf(L"%s\n",rest.lastErrorText());
            return;
        }

        // Verify that we received a 201 status code.
        if (rest.get_ResponseStatusCode() != 201) {
            // Examine the request/response to see what happened.
            wprintf(L"response status code = %d\n",rest.get_ResponseStatusCode());
            wprintf(L"response status text = %s\n",rest.responseStatusText());
            wprintf(L"response header: %s\n",rest.responseHeader());
            wprintf(L"response body (if any): %s\n",sbResponseBody.getAsString());
            wprintf(L"---\n");
            wprintf(L"LastRequestStartLine: %s\n",rest.lastRequestStartLine());
            wprintf(L"LastRequestHeader: %s\n",rest.lastRequestHeader());
            return;
        }

        i = i + 1;
    }

    fac.FileClose();

    // Now commit the blocks.
    // Let's have a look at the XML that will commit the blocks:
    const wchar_t *xmlStr = xml.getXml();
    wprintf(L"%s\n",xmlStr);

    // The XML will look like this:

    // <?xml version="1.0" encoding="utf-8" ?>
    // <BlockList>
    //     <Latest>MDAwMA==</Latest>
    //     <Latest>MDAwMQ==</Latest>
    //     <Latest>MDAwMg==</Latest>
    //     <Latest>MDAwMw==</Latest>
    //     <Latest>MDAwNA==</Latest>
    //     <Latest>MDAwNQ==</Latest>
    //     <Latest>MDAwNg==</Latest>
    //     <Latest>MDAwNw==</Latest>
    //     <Latest>MDAwOA==</Latest>
    //     <Latest>MDAwOQ==</Latest>
    //     <Latest>MDAxMA==</Latest>
    //     <Latest>MDAxMQ==</Latest>
    //     <Latest>MDAxMg==</Latest>
    //     <Latest>MDAxMw==</Latest>
    //     <Latest>MDAxNA==</Latest>
    //     <Latest>MDAxNQ==</Latest>
    //     <Latest>MDAxNg==</Latest>
    //     <Latest>MDAxNw==</Latest>
    // </BlockList>

    // --------------------------------------------------------------------------
    // IMPORTANT: Remove the Content-MD5 header previously set in the loop above.
    // --------------------------------------------------------------------------
    rest.RemoveHeader(L"Content-MD5");

    // Send the PUT Block List...
    const wchar_t *responseStr = rest.fullRequestString(L"PUT",L"/mycontainer/hamlet.xml?comp=blocklist",xmlStr);
    if (rest.get_LastMethodSuccess() != true) {
        wprintf(L"%s\n",rest.lastErrorText());
        return;
    }

    // When successful, the Azure Storage service will respond with a 201 response status code,
    // with no response body.

    if (rest.get_ResponseStatusCode() != 201) {
        // Examine the request/response to see what happened.
        wprintf(L"response status code = %d\n",rest.get_ResponseStatusCode());
        wprintf(L"response status text = %s\n",rest.responseStatusText());
        wprintf(L"response header: %s\n",rest.responseHeader());
        wprintf(L"response body (if any): %s\n",responseStr);
        wprintf(L"---\n");
        wprintf(L"LastRequestStartLine: %s\n",rest.lastRequestStartLine());
        wprintf(L"LastRequestHeader: %s\n",rest.lastRequestHeader());
        return;
    }

    wprintf(L"Success.\n");
    }