DataFlex

Adding x-ms-range header to Azure Blob Download

See more Azure Cloud Storage Examples

Demonstrates how to add an x-ms-range header to an Azure blob download. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoRest
    Boolean iBTls
    Integer iPort
    Boolean iBAutoReconnect
    Variant vAzAuth
    Handle hoAzAuth
    Variant vSb
    Handle hoSb
    String sTemp1
    Integer iTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatRest)) To hoRest
    If (Not(IsComObjectCreated(hoRest))) Begin
        Send CreateComObject of hoRest
    End

    // Connect to the Azure Storage Blob Service
    Move True To iBTls
    Move 443 To iPort
    Move True To iBAutoReconnect
    // In this example, the storage account name is "chilkat".
    Get ComConnect Of hoRest "chilkat.blob.core.windows.net" iPort iBTls iBAutoReconnect To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoRest To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Provide Azure Cloud credentials for the REST call.
    Get Create (RefClass(cComChilkatAuthAzureStorage)) To hoAzAuth
    If (Not(IsComObjectCreated(hoAzAuth))) Begin
        Send CreateComObject of hoAzAuth
    End
    Set ComAccessKey Of hoAzAuth To "AZURE_ACCESS_KEY"
    // The account name used here should match the 1st part of the domain passed in the call to Connect (above).
    Set ComAccount Of hoAzAuth To "chilkat"
    Set ComScheme Of hoAzAuth To "SharedKey"
    Set ComService Of hoAzAuth To "Blob"
    // This causes the "x-ms-version: 2021-08-06" header to be automatically added.
    Set ComXMsVersion Of hoAzAuth To "2021-08-06"
    Get pvComObject of hoAzAuth to vAzAuth
    Get ComSetAuthAzureStorage Of hoRest vAzAuth To iSuccess

    // 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.

    // Add the x-ms-range header.
    // See x-ms-range Header Format
    // The file we're downloading contains "Hello World!", so we'll download just the "World!" part..
    Get ComAddHeader Of hoRest "x-ms-range" "bytes=6-" To iSuccess

    // The Azure blob container is "test", the file is "helloWorld.txt"
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSb
    If (Not(IsComObjectCreated(hoSb))) Begin
        Send CreateComObject of hoSb
    End
    Get pvComObject of hoSb to vSb
    Get ComFullRequestNoBodySb Of hoRest "GET" "/test/helloWorld.txt" vSb To iSuccess
    If (iSuccess = False) Begin
        // Examine the request/response to see what happened.
        Get ComResponseStatusCode Of hoRest To iTemp1
        Showln "response status code = " iTemp1
        Get ComResponseStatusText Of hoRest To sTemp1
        Showln "response status text = " sTemp1
        Get ComResponseHeader Of hoRest To sTemp1
        Showln "response header: " sTemp1
        Showln "---"
        Get ComLastRequestStartLine Of hoRest To sTemp1
        Showln "LastRequestStartLine: " sTemp1
        Get ComLastRequestHeader Of hoRest To sTemp1
        Showln "LastRequestHeader: " sTemp1
        Procedure_Return
    End

    Get ComGetAsString Of hoSb To sTemp1
    Showln sTemp1

    Showln "Success."


End_Procedure