It's a REST service to obtain an OAuth 2.0 authorization token.
$ServerURL/oauth/gam/access_token
Client_id: Client ID of the application.
Grant_type: Grant_type of the flow.
Scope: Scope of the user account you wish to access.
Username: Username of the account you wish to access.
Password: Password of the account you wish to access.
&addstring = "client_id=be47d883307446b4b93fea47f9264f88&grant_type=password&scope=FullControl&username=test&password=test"
&getstring = &urlbase + "/oauth/access_token"
&httpclient.AddHeader("Content-Type", "application/x-www-form-urlencoded")
&httpclient.AddString(&addstring)
&httpclient.Execute("POST", &getstring)
&httpstatus = &httpclient.StatusCode
&result = &httpclient.ToString()
{
"access token" : "c9919e10e118",
"scope" : "FullControl"
}