call

# File actionpack/lib/action_dispatch/middleware/request_id.rb, line 20
    def call(env)
      env["action_dispatch.request_id"] = external_request_id(env) || internal_request_id
      status, headers, body = @app.call(env)

      headers["X-Request-Id"] = env["action_dispatch.request_id"]
      [ status, headers, body ]
    end