[
    {
      "user/{userId}/signup": {
        "parameters": {
          "userId": {
            "description": "Id of the user.",
            "schema": {
              "type": "string"
            }
          }
        },
        "subscribe": {
          "message": {
            "$ref": "#/components/messages/userSignedUp"
          }
        }
      }
    }
]