我基本上是在尝试将CherryPy教程中的示例部署到Heroku（https://docs.cherrypy.org/en/latest/tutorials.html#tutorial-8-make-it-smoother-with-ajax）。当我在本地运行代码时，一切正常。部署到Heroku后，我收到一些错误消息：
2020-04-16T17:42:19.422074+00:00 app[web.1]: Traceback (most recent call last):
2020-04-16T17:42:19.422076+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/cherrypy/_cprequest.py", line 670, in respond
2020-04-16T17:42:19.422076+00:00 app[web.1]: response.body = self.handler()
2020-04-16T17:42:19.422076+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/cherrypy/lib/encoding.py", line 217, in __call__
2020-04-16T17:42:19.422077+00:00 app[web.1]: self.body = self.oldhandler(*args, **kwargs)
2020-04-16T17:42:19.422077+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/cherrypy/_cpdispatch.py", line 61, in __call__
2020-04-16T17:42:19.422078+00:00 app[web.1]: return self.callable(*self.args, **self.kwargs)
2020-04-16T17:42:19.422078+00:00 app[web.1]: File "app.py", line 19, in GET
2020-04-16T17:42:19.422078+00:00 app[web.1]: return cherrypy.session['mystring']
2020-04-16T17:42:19.422079+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/cherrypy/__init__.py", line 246, in __getitem__
2020-04-16T17:42:19.422079+00:00 app[web.1]: return child[key]
2020-04-16T17:42:19.422079+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/cherrypy/lib/sessions.py", line 309, in __getitem__
2020-04-16T17:42:19.422080+00:00 app[web.1]: return self._data[key]
2020-04-16T17:42:19.422080+00:00 app[web.1]: KeyError: 'mystring'
2020-04-17T09:24:31.597650+00:00 app[web.1]: File "app.py", line 45, in <module>
2020-04-17T09:24:31.597765+00:00 app[web.1]: webapp.generator = StringGeneratorWebService()
2020-04-17T09:24:31.597768+00:00 app[web.1]: TypeError: expose_() missing 1 required positional argument: 'func'
2020-04-17T09:24:32.000000+00:00 app[api]: Build succeeded
我的Procfile仅包含
web: python app.py
我的猜测是，问题与css-trick有关，该css-trick避免刷新页面以显示请求结果。但是，正如您所看到的，我对部署完全陌生，这也是我对stackoverflow的第一个问题-因此，如果我在这里遗漏了一些明显的内容，请事先道歉。任何帮助深表感谢！