# File lib/oauth/rack/oauth_filter.rb, line 89
      def oauth2_token(request)
        request.params['bearer_token'] || request.params['access_token'] || (request.params["oauth_token"] && !request.params["oauth_signature"] ? request.params["oauth_token"] : nil )  ||
            request.env["HTTP_AUTHORIZATION"] &&
                !request.env["HTTP_AUTHORIZATION"][/(oauth_version="1.0")/] &&
                request.env["HTTP_AUTHORIZATION"][/^(Bearer|OAuth|Token) (token=)?([^\s]*)$/, 3]
      end