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Visual Basic 6.0

Get XOAUTH2 Access Token from Google OAuth 2.0 Authorization Server

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Obtains an OAUTH2 access token from the Google OAuth 2.0 Authorization Server. This is for Server to server applications using Google API's that need an access token. See https://developers.google.com/accounts/docs/OAuth2ServiceAccount

Chilkat Visual Basic 6.0 Downloads

Visual Basic 6.0
Dim success As Long
success = 0

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

Dim http As New ChilkatHttp

' --------------------------------------------------------------------------------
' For a step-by-step guide for setting up your Google Workspace service account,
' see Setup Google Workspace Account for Sending SMTP GMail from a Service Account
' --------------------------------------------------------------------------------
' Begin by loading your Google service account key (.p12)
Dim cert As New ChilkatCert
success = cert.LoadPfxFile("c:/someDirectory/keys/chilkat25-cbd7b42afbd8.p12","notasecret")
If (success <> 1) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

' The ISS is your service account email address ending in gserviceaccount.com.
Dim iss As String
iss = "chilkatsvc@chilkat25.iam.gserviceaccount.com"

' The scope is always the following string:
Dim scope As String
scope = "https://mail.google.com/"

' The sub is your company email address
Dim oauth_sub As String
oauth_sub = "bob@yourcompany.com"

' The access token is valid for this number of seconds.
Dim numSec As Long
numSec = 3600

Dim accessToken As String
accessToken = http.G_SvcOauthAccessToken(iss,scope,oauth_sub,numSec,cert)
If (http.LastMethodSuccess <> 1) Then
    Debug.Print http.LastErrorText
    Exit Sub
Else
    Debug.Print "access token: " & accessToken
End If

' The access token allows us to send unlimited emails while it's valid. Once it expires, we must obtain and use a new one.