DataFlex

Azure Storage: CORS Preflight Blob Request

See more Azure Cloud Storage Examples

Azure Storage Blob Service REST API: Sample code to send a CORS pre-flight blob request. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoRest
    Boolean iBTls
    Integer iPort
    Boolean iBAutoReconnect
    Variant vAzAuth
    Handle hoAzAuth
    String sResponseStr
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    Move False To iSuccess

    // Azure Blob Service Example: CORS Preflight Blob Request
    // See also: https://msdn.microsoft.com/en-us/library/azure/dn535599.aspx

    // 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: x-ms-date, Authorization.  These headers
    // are automatically set by Chilkat.

    // The preflight blob request requires the following two HTTP headers.
    // The Origin is the domain from which the actual request will be issued.
    Get ComAddHeader Of hoRest "Origin" "www.contoso.com" To iSuccess
    // The Access-Control-Request-Method is the HTTP method (such as GET, POST, PUT, etc.) of the actual request.
    Get ComAddHeader Of hoRest "Access-Control-Request-Method" "PUT" To iSuccess

    // The expected response is a 202 response status code with no response body.
    // The name of the container or blob resource in this example is "test". (Replace "test" with your container name.)
    Get ComFullRequestNoBody Of hoRest "OPTIONS" "/test" To sResponseStr
    Get ComLastMethodSuccess Of hoRest To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoRest To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // When successful, the Azure Storage service will respond with a 200 response code,
    // with no response body.

    // If CORS is not enabled or no matching rule is found for the request, 
    // then a 403 status code is returned, with the following status text:
    // "CORS not enabled or no matching rule found for this request."
    Get ComResponseStatusCode Of hoRest To iTemp1
    If (iTemp1 <> 200) 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 "response body (if any): " sResponseStr
        Showln "---"
        Get ComLastRequestStartLine Of hoRest To sTemp1
        Showln "LastRequestStartLine: " sTemp1
        Get ComLastRequestHeader Of hoRest To sTemp1
        Showln "LastRequestHeader: " sTemp1
        Procedure_Return
    End

    Showln "Success: Preflight Blob Request is accepted."


End_Procedure