# File lib/googleauth/compute_engine.rb, line 63
        def on_gce? options = {}
          c = options[:connection] || Faraday.default_connection
          resp = c.get COMPUTE_CHECK_URI do |req|
            # Comment from: oauth2client/client.py
            #
            # Note: the explicit `timeout` below is a workaround. The underlying
            # issue is that resolving an unknown host on some networks will take
            # 20-30 seconds; making this timeout short fixes the issue, but
            # could lead to false negatives in the event that we are on GCE, but
            # the metadata resolution was particularly slow. The latter case is
            # "unlikely".
            req.options.timeout = 0.1
          end
          return false unless resp.status == 200
          return false unless resp.headers.key? "Metadata-Flavor"
          resp.headers["Metadata-Flavor"] == "Google"
        rescue Faraday::TimeoutError, Faraday::ConnectionFailed
          false
        end