Running a Dash app within a Flask app

Solution 1:

From the docs:

The underlying Flask app is available at app.server.

import dash
app = dash.Dash(__name__)
server = app.server

You can also pass your own Flask app instance into Dash:

import flask
server = flask.Flask(__name__)
app = dash.Dash(__name__, server=server)

Now that you have the Flask instance, you can add whatever routes and other functionality you need.

@server.route('/hello')
def hello():
    return 'Hello, World!'

To the more general question "how can I serve two Flask instances next to each other", assuming you don't end up using one instance as in the above Dash answer, you would use DispatcherMiddleware to mount both applications.

dash_app = Dash(__name__)
flask_app = Flask(__name__)

application = DispatcherMiddleware(flask_app, {'/dash': dash_app.server})

Solution 2:

Set url_base_pathname in your Dash instance.

app_flask = flask.Flask(__name__)

app_dash = dash.Dash(__name__, server=app_flask, url_base_pathname='/pathname')

Now you can redirect to your Plotly Dashboard app under any Flask routes you want.

@app_flask.route('/plotly_dashboard') 
def render_dashboard():
    return flask.redirect('/pathname')