Authentificate and authorize to Google APIs

GoogleApi.kt

    // Access scopes
    private val accessScope = listOf("https://www.googleapis.com/auth/cloud-platform.read-only")
    private var token = "Empty"

    // Receive Google OAuth 2 token for API access
    private fun authenticateAndAuthorize() {
        doAsync {
            val googleCredential = GoogleCredential
                .fromStream(ctx.assets.open("service-account.json"))
                .createScoped(accessScope)
            googleCredential.refreshToken()
            this@BigQueryAPI.token = googleCredential.accessToken
        }
    }