This introduces our first official support for a Review Board Docker

image. This is carefully crafted to provide a full Review Board

environment with all necessary packages and with configuration options

that should meet the needs of our customers.
Our Docker image is based on Ubuntu 20.04 LTS, which offers 10 years of

security updates. It uses Gunicorn as the WSGI server, leveraging the

new reviewboard.wsgi module, and supports MySQL/MariaDB or Postgres

databases.
The image also comes pre-installed with Power Pack and Review Bot

extensions. Additional extensions can be installed by creating a new

Dockerfile that inherits from ours, installing any extensions or other

packages needed by the customer. This helps give consumers the control

they need without requiring that they fork ours.
Documentation has been added to the Admin Guide on using Docker for

installation. This covers basic usage via docker run, more

comprehensive architectures using docker-compose (which we include

sample files for), launch-time configuration options, and how to extend

the image to include other extensions.
Currently, this Dockerfile is geared toward Review Board 3.0.21 support.

Additional work will be done on the release-4.0.x branch to bring

compatibility with Review Board 4.0 RC1 and Python 3.

Built the Docker image and ran it. Hooked it up to Nginx and verified

I had a working setup.
Used both the MySQL and Postgres docker-compose.yaml files and deployed

a whole infrastructure. Logged in, verified I could add repositories and

post review requests.
Built the docs. Checked for build errors, bad links, and spelling errors.
Ran through the examples in the docs for building custom images with

custom extensions, ensuring they worked as expected.
Tested the options to the build.py for the Dockerfile, including

uploading a build to our repository on Docker Hub

(https://hub.docker.com/r/beanbag/reviewboard/)
This will likely need a lot more real-world testing in real-world

deployments.