(Go) 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.

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    // 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.

    rest := chilkat.NewRest()

    // Connect to the Azure Storage Blob Service
    bTls := true
    port := 443
    bAutoReconnect := true
    // In this example, the storage account name is "chilkat".
    success := rest.Connect("chilkat.blob.core.windows.net",port,bTls,bAutoReconnect)
    if success != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    // Provide Azure Cloud credentials for the REST call.
    azAuth := chilkat.NewAuthAzureStorage()
    azAuth.SetAccessKey("AZURE_ACCESS_KEY")
    // The account name used here should match the 1st part of the domain passed in the call to Connect (above).
    azAuth.SetAccount("chilkat")
    azAuth.SetScheme("SharedKey")
    azAuth.SetService("Blob")
    // This causes the "x-ms-version: 2021-08-06" header to be automatically added.
    azAuth.SetXMsVersion("2021-08-06")
    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..
    xml := chilkat.NewXml()
    xml.SetTag("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
    fac := chilkat.NewFileAccess()
    success = fac.OpenForRead("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...)
    blockSize := 16384

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

    crypt := chilkat.NewCrypt2()
    crypt.SetHashAlgorithm("md5")

    sbResponseBody := chilkat.NewStringBuilder()
    uriPath := chilkat.NewStringBuilder()
    var blockId *string = new(string)
    dataBlock := chilkat.NewBinData()
    var contentMd5 *string = new(string)
    i := 0
    for i < numBlocks {

        dataBlock.Clear()
        success = fac.ReadBlockBd(i,blockSize,dataBlock)
        if success == false {
            fmt.Println(fac.LastErrorText())
            rest.DisposeRest()
            azAuth.DisposeAuthAzureStorage()
            xml.DisposeXml()
            fac.DisposeFileAccess()
            crypt.DisposeCrypt2()
            sbResponseBody.DisposeStringBuilder()
            uriPath.DisposeStringBuilder()
            dataBlock.DisposeBinData()
            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,"base64")

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

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

        contentMd5 = *crypt.HashBdENC(dataBlock)
        rest.AddHeader("Content-MD5",*contentMd5)

        // Upload this block..
        sbResponseBody.Clear()
        success = rest.FullRequestBd("PUT",*uriPath.GetAsString(),dataBlock,sbResponseBody)
        if success == false {
            fmt.Println(rest.LastErrorText())
            rest.DisposeRest()
            azAuth.DisposeAuthAzureStorage()
            xml.DisposeXml()
            fac.DisposeFileAccess()
            crypt.DisposeCrypt2()
            sbResponseBody.DisposeStringBuilder()
            uriPath.DisposeStringBuilder()
            dataBlock.DisposeBinData()
            return
        }

        // Verify that we received a 201 status code.
        if rest.ResponseStatusCode() != 201 {
            // Examine the request/response to see what happened.
            fmt.Println("response status code = ", rest.ResponseStatusCode())
            fmt.Println("response status text = ", rest.ResponseStatusText())
            fmt.Println("response header: ", rest.ResponseHeader())
            fmt.Println("response body (if any): ", *sbResponseBody.GetAsString())
            fmt.Println("---")
            fmt.Println("LastRequestStartLine: ", rest.LastRequestStartLine())
            fmt.Println("LastRequestHeader: ", rest.LastRequestHeader())
            rest.DisposeRest()
            azAuth.DisposeAuthAzureStorage()
            xml.DisposeXml()
            fac.DisposeFileAccess()
            crypt.DisposeCrypt2()
            sbResponseBody.DisposeStringBuilder()
            uriPath.DisposeStringBuilder()
            dataBlock.DisposeBinData()
            return
        }

        i = i + 1
    }

    fac.FileClose()

    // Now commit the blocks.
    // Let's have a look at the XML that will commit the blocks:
    xmlStr := xml.GetXml()
    fmt.Println(*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("Content-MD5")

    // Send the PUT Block List...
    responseStr := rest.FullRequestString("PUT","/mycontainer/hamlet.xml?comp=blocklist",*xmlStr)
    if rest.LastMethodSuccess() != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        azAuth.DisposeAuthAzureStorage()
        xml.DisposeXml()
        fac.DisposeFileAccess()
        crypt.DisposeCrypt2()
        sbResponseBody.DisposeStringBuilder()
        uriPath.DisposeStringBuilder()
        dataBlock.DisposeBinData()
        return
    }

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

    if rest.ResponseStatusCode() != 201 {
        // Examine the request/response to see what happened.
        fmt.Println("response status code = ", rest.ResponseStatusCode())
        fmt.Println("response status text = ", rest.ResponseStatusText())
        fmt.Println("response header: ", rest.ResponseHeader())
        fmt.Println("response body (if any): ", *responseStr)
        fmt.Println("---")
        fmt.Println("LastRequestStartLine: ", rest.LastRequestStartLine())
        fmt.Println("LastRequestHeader: ", rest.LastRequestHeader())
        rest.DisposeRest()
        azAuth.DisposeAuthAzureStorage()
        xml.DisposeXml()
        fac.DisposeFileAccess()
        crypt.DisposeCrypt2()
        sbResponseBody.DisposeStringBuilder()
        uriPath.DisposeStringBuilder()
        dataBlock.DisposeBinData()
        return
    }

    fmt.Println("Success.")

    rest.DisposeRest()
    azAuth.DisposeAuthAzureStorage()
    xml.DisposeXml()
    fac.DisposeFileAccess()
    crypt.DisposeCrypt2()
    sbResponseBody.DisposeStringBuilder()
    uriPath.DisposeStringBuilder()
    dataBlock.DisposeBinData()