B4X

Azure Storage: Upload Empty File to Block Blob

See more Azure Cloud Storage Examples

Demonstrates how to create an empty block blob in Azure Storage. B4X

Dim success As Boolean = False

'  Azure Blob Service Example: Demonstrates how to create an empty block blob.
'  See also: https://msdn.microsoft.com/en-us/library/azure/dd179451.aspx

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

Dim rest As ChilkatRest
rest.Initialize("rest")

'  Connect to the Azure Storage Blob Service
Dim bTls As Boolean = True
Dim port As Int = 443
Dim bAutoReconnect As Boolean = True
'  In this example, the storage account name is "chilkat".
success = rest.Connect("chilkat.blob.core.windows.net", port, bTls, bAutoReconnect)
If success <> True Then
    Log(rest.LastErrorText)
    Return
End If


'  Provide Azure Cloud credentials for the REST call.
Dim azAuth As ChilkatAuthAzureStorage
azAuth.Initialize
azAuth.AccessKey = "AZURE_ACCESS_KEY"
'  The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.Account = "chilkat"
azAuth.Scheme = "SharedKey"
azAuth.Service = "Blob"
'  This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.XMsVersion = "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.

'  IMPORTANT: Make sure to set the x-ms-blob-type header:
success = rest.AddHeader("x-ms-blob-type", "BlockBlob")

'  To create an empty blob, upload a zero-length string.
Dim responseStr As String = rest.FullRequestString("PUT", "/mycontainer/empty.txt", "")
If rest.LastMethodSuccess <> True Then
    Log(rest.LastErrorText)
    Return
End If


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

If rest.ResponseStatusCode <> 201 Then
    '  Examine the request/response to see what happened.
    Log("response status code = " & rest.ResponseStatusCode)
    Log("response status text = " & rest.ResponseStatusText)
    Log("response header: " & rest.ResponseHeader)
    Log("response body (if any): " & responseStr)
    Log("---")
    Log("LastRequestStartLine: " & rest.LastRequestStartLine)
    Log("LastRequestHeader: " & rest.LastRequestHeader)
    Return
End If


Log("Success.")