带女服务员的 Python Dash 服务器

Question

我有一个用 Dash 框架编写的仪表板应用程序。它还具有一些使用 Flask 编写的 Restful API。我正在将 Flask 应用程序添加到 Dash 服务器，如下所示

import dash
import flask
import dash_bootstrap_components as dbc

flask_server = flask.Flask(__name__)
app = dash.Dash(__name__,server=flask_server, external_stylesheets=[dbc.themes.BOOTSTRAP])

并且正在运行服务器

from dashboard import app
from waitress import serve

if __name__ == "__main__":
    app.title = 'Litmus'
    app.run_server(debug=False)
    # serve(app,host="0.0.0.0",port=8050)

上面的代码在我使用时工作正常app.run_server(debug=False)，但当我使用 waitress 运行服务器时它会抛出异常。当我使用以下几行时

#app.run_server(debug=False)
serve(app,host="0.0.0.0",port=8050)

我收到以下错误

ERROR:waitress:Exception while serving /
Traceback (most recent call last):
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\channel.py", line 397, in service
    task.service()
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\task.py", line 168, in service
    self.execute()
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\task.py", line 434, in execute
    app_iter = self.channel.server.application(environ, start_response)
TypeError: 'Dash' object is not callable
ERROR:waitress:Exception while serving /favicon.ico
Traceback (most recent call last):
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\channel.py", line 397, in service
    task.service()
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\task.py", line 168, in service
    self.execute()
  File "C:\Users\litmus\AppData\Roaming\Python\Python38\site-packages\waitress\task.py", line 434, in execute
    app_iter = self.channel.server.application(environ, start_response)
TypeError: 'Dash' object is not callable

Answer 1

它不起作用，因为您将 Dash 应用程序而不是 Flask 应用程序传递给serve.

所以代替这个：

serve(app,host="0.0.0.0",port=8050)

像这样传递 Flask 应用程序实例：

serve(app.server, host="0.0.0.0", port=8050)