(VB.NET) Get a Google Drive Access Token using a JSON Private Key

Demonstrates how to get a Google Drive API access token using a JSON service account private key.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

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

' First load the JSON key into a string.
Dim fac As New Chilkat.FileAccess
Dim jsonKey As String = fac.ReadEntireTextFile("qa_data/googleApi/chilkatcloud-b8826e030499.json","utf-8")
If (fac.LastMethodSuccess <> True) Then
    Debug.WriteLine(fac.LastErrorText)
    Exit Sub
End If


Dim gAuth As New Chilkat.AuthGoogle
gAuth.JsonKey = jsonKey

' Choose a scope.
gAuth.Scope = "https://www.googleapis.com/auth/drive"

' Request an access token that is valid for this many seconds.
gAuth.ExpireNumSeconds = 3600

' If the application is requesting delegated access:
' The email address of the user for which the application is requesting delegated access,
' then set the email address here. (Otherwise leave it empty.)
gAuth.SubEmailAddress = ""

' Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
' The Chilkat socket object is used so that the connection can be established
' through proxies or an SSH tunnel if desired.
Dim tlsSock As New Chilkat.Socket
Dim success As Boolean = tlsSock.Connect("www.googleapis.com",443,True,5000)
If (success <> True) Then
    Debug.WriteLine(tlsSock.LastErrorText)
    Exit Sub
End If


' Send the request to obtain the access token.
success = gAuth.ObtainAccessToken(tlsSock)
If (success <> True) Then
    Debug.WriteLine(gAuth.LastErrorText)
    Exit Sub
End If


' Examine the access token:
Debug.WriteLine("Access Token: " & gAuth.AccessToken)