Get user's google profile by token in Kotlin

build.gradle.kts

implementation("com.google.auth:google-auth-library-oauth2-http:0.20.0")
implementation("com.google.http-client:google-http-client-gson:1.35.0")
implementation("com.google.apis:google-api-services-oauth2:v2-rev157-1.25.0")

GoogleController.kt

// <...>
// assuming:
// userToken: String - received token from client

private val googleNetHttpTransport = GoogleNetHttpTransport.newTrustedTransport()
private val googleJsonFactory = GsonFactory()

private val oauth2Api = Oauth2.Builder(
    googleNetHttpTransport,
    googleJsonFactory,
    HttpCredentialsAdapter(OAuth2Credentials.create(
        AccessToken(userToken, null)
    ))
  )
  .build()

private val userInfo = oauth2Api.Userinfo().v2().Me().get()
  .execute()

println(userInfo)
// check for class info here:
// https://developers.google.com/resources/api-libraries/documentation/oauth2/v2/csharp/latest/classGoogle_1_1Apis_1_1Oauth2_1_1v2_1_1Data_1_1Userinfo.html