Xbase++

Azure Storage: Download Blob to File

See more Azure Cloud Storage Examples

Sample code to download an Azure blob to a file. Xbase++

LOCAL nSuccess
LOCAL oRest
LOCAL nBTls
LOCAL nPort
LOCAL nBAutoReconnect
LOCAL oAzAuth
LOCAL oFileStream
LOCAL nExpectedStatus
LOCAL cResponseStr

nSuccess := 0

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

oRest := CreateObject("Chilkat.Rest")

//  Connect to the Azure Storage Blob Service
nBTls := 1
nPort := 443
nBAutoReconnect := 1
//  In this example, the storage account name is "chilkat".
nSuccess := oRest:Connect("chilkat.blob.core.windows.net", nPort, nBTls, nBAutoReconnect)
IF (nSuccess != 1)
    ? oRest:LastErrorText
    oRest:destroy()
    RETURN
ENDIF

//  Provide Azure Cloud credentials for the REST call.
oAzAuth := CreateObject("Chilkat.AuthAzureStorage")
oAzAuth:AccessKey := "AZURE_ACCESS_KEY"
//  The account name used here should match the 1st part of the domain passed in the call to Connect (above).
oAzAuth:Account := "chilkat"
oAzAuth:Scheme := "SharedKey"
oAzAuth:Service := "Blob"
//  This causes the "x-ms-version: 2021-08-06" header to be automatically added.
oAzAuth:XMsVersion := "2021-08-06"
nSuccess := oRest:SetAuthAzureStorage(oAzAuth)

//  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.

//  Setup a file stream for the download
oFileStream := CreateObject("Chilkat.Stream")
oFileStream:SinkFile := "C:/temp/qa_output/starfish.jpg"

//  Indicate that the call to FullRequestNoBody should send the response body
//  to fileStream if the response status code is 200.
//  If a non-success response status code is received, then nothing
//  is streamed to the output file and the error response is returned by FullRequestNoBody.
nExpectedStatus := 200
oRest:SetResponseBodyStream(nExpectedStatus, 1, oFileStream)

//  The Azure blob container is "test", the file is "starfish.jpg"
cResponseStr := oRest:FullRequestNoBody("GET", "/test/starfish.jpg")
IF (oRest:LastMethodSuccess != 1)

    //  Examine the request/response to see what happened.
    ? "response status code = " + Str(oRest:ResponseStatusCode)
    ? "response status text = " + oRest:ResponseStatusText
    ? "response header: " + oRest:ResponseHeader
    ? "response body (if any): " + cResponseStr
    ? "---"
    ? "LastRequestStartLine: " + oRest:LastRequestStartLine
    ? "LastRequestHeader: " + oRest:LastRequestHeader
    oRest:destroy()
    oAzAuth:destroy()
    oFileStream:destroy()
    RETURN
ENDIF

? "Success."

oRest:destroy()
oAzAuth:destroy()
oFileStream:destroy()