Deploying Dash Apps
By default, Dash apps run on localhost—you can only access them on your
own machine. To share a Dash app, you need to deploy it to a server.
Our recommend method for securely deploying Dash apps is
Dash Enterprise.
Dash Enterprise can be installed on the cloud services of AWS, Azure, or Google.
Dash Enterprise Deployment
Dash Enterprise
is Plotly’s commercial product for developing and deploying
Dash apps. In addition to proven, Git-based deployment, the Dash Enterprise platform provides a complete Analytical App Stack.
This includes:
- LDAP and SAML Authentication Middleware
- Data App Workspaces
- Job Queue Support
- Enterprise-Wide Dash App Portal
- Design Kit
- Reporting, Alerting, Saved Views, and PDF Reports
- Dashboard Toolkit
- Embedding Dash apps in Existing websites or Salesforce
- AI App Catalog
- Big Data Best Practices
Heroku for Sharing Public Dash Apps
Heroku is one of the most trusted platforms for deploying and managing public Flask
applications. The Git and buildpack-based deployment of Heroku and Dash Enterprise
are nearly identical, enabling a smooth transition to Dash Enterprise if you
are already using Heroku. View the official Heroku guide to Python.
Here is a simple example for deploying a Dash app to Heroku. This example requires a Heroku account,
git, and virtualenv.
Step 1. Create a new folder for your project:
$ mkdir dash_app_example
$ cd dash_app_example
Step 2. Initialize the folder with git and a virtualenv
$ git init # initializes an empty git repo
$ virtualenv venv # creates a virtualenv called "venv"
$ source venv/bin/activate # uses the virtualenv
virtualenv creates a fresh Python instance. You will need to reinstall your
app’s dependencies with this virtualenv:
$ pip install dash
$ pip install plotly
You will also need a new dependency, gunicorn, for deploying the app:
$ pip install gunicorn
Step 3. Initialize the folder with a sample app (app.py), a .gitignore file, requirements.txt, and a Procfile for deployment
Create the following files in your project folder:
app.py
from dash import Dash, dcc, html, Input, Output, callback
import os
external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']
app = Dash(__name__, external_stylesheets=external_stylesheets)
server = app.server
app.layout = html.Div([
html.H1('Hello World'),
dcc.Dropdown(['LA', 'NYC', 'MTL'],
'LA',
id='dropdown'
),
html.Div(id='display-value')
])
@callback(Output('display-value', 'children'), Input('dropdown', 'value'))
def display_value(value):
return f'You have selected {value}'
if __name__ == '__main__':
app.run(debug=True)
.gitignore
venv
*.pyc
.DS_Store
.env
Procfile
web: gunicorn app:server
(Note that app refers to the filename app.py.
server refers to the variable server inside that file).
requirements.txt
requirements.txt describes your Python dependencies.
You can fill this file in automatically with:
$ pip freeze > requirements.txt
Step 4. Initialize Heroku, add files to Git, and deploy
$ heroku create my-dash-app # change my-dash-app to a unique name
$ git add . # add all files to git
$ git commit -m 'Initial app boilerplate'
$ git push heroku master # deploy code to heroku
$ heroku ps:scale web=1 # run the app with a 1 heroku "dyno"
You should be able to view your app at https://my-dash-app.herokuapp.com
(changing my-dash-app to the name of your app).
Step 5. Update the code and redeploy
When you modify app.py with your own code, you will need to add the changes
to Git and push those changes to Heroku.
$ git status # view the changes
$ git add . # add all the changes
$ git commit -m 'a description of the changes'
$ git push heroku master
This workflow for deploying apps on Heroku is very similar to how deployment
works with Plotly’s Dash Enterprise.
Dash Enterprise 5.2.X further simplifies deployment by providing a CLI that handles these Git operations
with a single de deploy command.