How do I host a Dash app on an Apache Server?

Question

I’m new to hosting a Raspberry Pi Apache server and I have a simple Dash application I would like to host via a .wsgi file. Following Flask’s official documentation, this post’s answer, modwsgi’s documentation, and this guide for connecting Flask to Apache; I was able to get my files and structure to the state it is in below, but navigating to http://#.#.#.#/dash returns a 404, while http://#.#.#.# navigates to the default Apache page. I’m sure I am missing something and that it is relatively straight forward, I’m just not sure what. The apache error log has no errors or abnormalities.

dash.py

from datetime import date
import dash
import dash_table
import dash_core_components as dcc
import dash_html_components as html
import pandas as pd

import data_controller as dc

external_stylesheets = ['/style.css']

data = dc.Data()

app = dash.Dash(__name__, external_stylesheets=external_stylesheets, requests_pathname_prefix='/dash/')
server = app.server

def serve_layout():
    data = dc.Data()

    today = date.today()

    df = data.display_data()

    return dcc.Tabs([
        html.H1([children='Hello Apache!']),
        dash_table.DataTable(columns=[{'name':i,'id':i} for i in df.columns],data=df.loc[:].to_dict('records'))
    ])

app.layout = serve_layout

if __name__ == '__main__':
    app.run_server(debug=True, host='0.0.0.0')

/etc/apache2/sites-available/dash.conf

WSGIDaemonProcess dash user=pi group=pi home=/home/pi/Documents/programming/ threads=5
WSGIScriptAlias /dash /var/www/html/wsgi/dash.wsgi

WSGIProcessGroup dash
WSGIApplicationGroup %{GLOBAL}

/var/www/html/wsgi/dash.wsgi

#!/usr/bin/python
import sys
sys.path.insert(0,'/home/pi/Documents/programming/dashboard/')
from dash import server as application

Asked By: SourPatchAdult

||

Source

Answer 1

As suspected, the answer was very simple, just not obvious in the resources I used. This walkthrough reminded me that I need to establish a virtual path between a2ensite and my .config file using the command sudo /usr/sbin/a2ensite dash.conf

Answered By: SourPatchAdult

Answer 2

I am using Ubuntu 20.04 and have created a customized virtual enviroment.

First I ran:

sudo apt-get install libapache2-mod-wsgi-py3

While in the Folder

sudo chown -R www-data *
sudo chmod -R 775 *

For a multi page app, I tried to do as minimun as possible, i just copy and paste this code: https://dash.plotly.com/urls:

Then customize the files:

app.py

Located in a folder /var/www/html/Dash

from dash import Dash, html, dcc
import dash

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']

app = Dash(__name__, 
           external_stylesheets=external_stylesheets,
           use_pages=True,
           requests_pathname_prefix='/Dash/')

server = app.server
app.scripts.config.serve_locally = True
app.css.config.serve_locally = True

app.layout = html.Div([
    html.H1('Multi-page app with Dash Pages'),

    html.Div(
        [
            html.Div(
                dcc.Link(
                    f"{page['name']} - {page['path']}", href=page["relative_path"]
                )
            )
            for page in dash.page_registry.values()
        ]
    ),

    dash.page_container
])

if __name__ == '__main__':
    app.run_server(debug=True,  port='8050')

dash.conf

Located in a folder /etc/apache2/sites-available

<VirtualHost *:80>
    ServerName 10.0.10.10
    ServerAdmin user@localhost
    DocumentRoot /var/www/html/Dash

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

    WSGIDaemonProcess Dash threads=5 user=www-data group=www-data python-path=/home/user/env/pweb/lib/python3.8/site-packages python-home=/home/user/env/pweb

    WSGIScriptAlias /Dash /var/www/html/Dash/wsgi.py

    <Files wsgi.py>
        Require all granted
    </Files>

    <Directory /var/www/html/Dash>
            AddHandler wsgi-script .py
            WSGIProcessGroup Dash
            WSGIApplicationGroup %{GLOBAL}
            WSGIScriptReloading On
            Allow from all
            Options Indexes FollowSymLinks MultiViews ExecCGI
            Require all granted
    </Directory>

</VirtualHost>

Right after

a2ensite dash

wsgi.py
Located in a folder /var/www/html/Dash

import sys

sys.path.insert(0,"/var/www/html/Dash/")
sys.path.insert(0,"/home/user/env/pweb/lib/python3.8/site-packages")
sys.path.insert(0,"/home/user/env/pweb")

from app import server as application

To track problems while running I ran the commands:

tail -200 /var/log/apache2/error.log
systemctl status apache2.service

Answered By: e.jimenez

How do I host a Dash app on an Apache Server?

Question:

dash.py

/etc/apache2/sites-available/dash.conf

/var/www/html/wsgi/dash.wsgi

Answers: