(Xojo Plugin) Download Object from Google Cloud Storage

Demonstrates how to download an object from Google Cloud Storage to a file.

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

//  This example uses a previously obtained access token having permission for the
//  scope "https://www.googleapis.com/auth/cloud-platform"

//  In this example, Get Google Cloud Storage OAuth2 Access Token,
//  the service account access token was saved to a text file.  This example fetches the access token from the file..
Dim sbToken As New Chilkat.StringBuilder
success = sbToken.LoadFile("qa_data/tokens/googleCloudStorageAccessToken.txt","utf-8")

//  Send a GET equivalent to this curl command.

//  curl -X GET \
//      -H "Authorization: Bearer [OAUTH2_TOKEN]" \
//      -o "[SAVE_TO_LOCATION]" \
//      "https://www.googleapis.com/storage/v1/b/[BUCKET_NAME]/o/[OBJECT_NAME]?alt=media"

Dim http As New Chilkat.Http

http.AuthToken = sbToken.GetAsString()

//  Construct a URL to download an object named "starfish.jpg" from the "chilkat-ocean" bucket.
success = http.SetUrlVar("bucket_name","chilkat-ocean")
success = http.SetUrlVar("object_name","starfish.jpg")
Dim url As String
url = "https://www.googleapis.com/storage/v1/b/{$bucket_name}/o/{$object_name}?alt=media"

//  If there is an error response, then we didn't actually download the file data,
//  but instead we downloaded an error response..
Dim fileData As New Chilkat.BinData
Dim success As Boolean
success = http.DownloadBd(url,fileData)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

Dim sbErrorResponse As New Chilkat.StringBuilder
Dim responseCode As Int32
responseCode = http.LastStatus
If (responseCode = 401) Then
    System.DebugLog("If invalid credentials, then it is likely the access token expired.")
    System.DebugLog("Your app should automatically fetch a new access token and re-try.")
End If

If (responseCode <> 200) Then
    //  Get the error response
    success = sbErrorResponse.AppendBd(fileData,"utf-8",0,0)
    System.DebugLog("Error response code = " + Str(responseCode))
    System.DebugLog("Error:")
    System.DebugLog(sbErrorResponse.GetAsString())
    Return
End If

System.DebugLog("Success.")

//  Save the downloaded data to a file.
success = fileData.WriteFile("qa_output/starfish.jpg")