In this repository, I have layed out the barebones 'skeleton' for a docker-compose setup of Home Assistant on a Raspberry Pi 4 microcomputer. My Home Assistant installation is modelled after this very clear guide from Jere's website iotechonline.com.
This guide will get you all the way to the Home Assistant onboarding script.

• Make sure everything is up-to-date:

  sudo apt-get update && sudo apt-get upgrade

• Install Docker according to the docs.

  curl -fsSL https://get.docker.com -o get-docker.sh sudo sh get-docker.sh: execute the install script with root priviledges

  It is best practice to add your user to the Docker group so that containers can be run without requiring root priveleges.
  Verify that the regular user has permissions for docker with the command: groups ${USER}
  If not, then go ahead and add your user to the group Docker (and verify that it was successful):
  sudo usermod -aG docker pi && groups ${USER}
  (syntax: sudo usermod -aG docker [user_name], in Raspberry Pi OS, the default user is 'pi')

  *You must restart the user session (i.e., log out and back in) for this change to take effect.

• Docker compose:

  The latest versions of Docker Desktop actually have compose v2 built in to the command line interface (CLI). Docker Desktop for Linux is still in development, but we can add access to Compose v2 through the Linux Docker Engine CLI using the instructions & convenience script offered by the Docker team:
  Since this is being installed on a Raspberry Pi 4, we must substitute the url for the latest build on 64-bit ARM architecture in place of x86-64, and execute the following commands:
  mkdir -p ~/.docker/cli-plugins/
curl -SL https://github.com/docker/compose/releases/download/v2.2.3/docker-compose-linux-aarch64 -o ~/.docker/cli-plugins/docker-compose
chmod +x ~/.docker/cli-plugins/docker-compose: change the permissions on the binary to executable.
  docker compose version: Check that everything is installed.

  If you are running 32-bit Raspberry Pi OS (or other linux distribution), make sure to substitute the URL appropriately!

• Copy project folder
• modify .env.sample and secrets.yaml.sample
• execute docker-compose

To get started, navigate to where you want to locate your Home Assistant folder.
cd ~ (I prefer it to be in my user's home directory)

Then, bring this repo folder and it's contents to your computer:
git clone https://github.com/kklitzing/home-assistant
If you don't have git installed, fret not. On this page, simply click on the green box that says Code and select Download ZIP. Extract the ZIP archive into the desired directory.

• Copy project folder
• modify .env.sample and secrets.yaml.sample
• execute docker-compose

If this is your first time with HA, you have to edit (or replace) just two files: .env and secrets.yaml
If you are restoring your existing HA setup, then additionally make sure to combine the lines from this repo's configuration.yaml and secrets.yaml when restoring your own.

• The .env file holds variables that the docker-compose command will refer to when it builds the containers.
  First open the .env.sample file within the base directory with your choice of text editor: cd home-assistant nano .env.sample

  MYSQL_ROOT_PASSWORD=mariadbrootpassword
  HA_MYSQL_PASSWORD=ha_dbdatabasepassword
  PUID=1000
  PGID=1000
  

  The variables PUID and PGID are the User ID and Group ID under which Docker will run these Processes).
  The defaults should be suitable on a Raspberry Pi, but if not, check the UID/GID for your user with the command id
  Be sure to change the passwords to something unique:

  After editing, using Ctrl-O will give you the option to save with a different filename. Save without the suffix .sample and exit.

• The secrets.yaml file is where Home Assistant will look whenever it sees a !secret reference its configuration.yaml file. These secrets are are generally things like service/server passwords, but can also be non-sensitive things like ip addresses that you'd just prefer to leave out of the config file, but are still needed for setup/interaction with the other software containers.
  By doing this, we'll get a jump-start on following best practices and at the same time make it easy to safely share your config or troubleshoot your file with others without having to redact your passwords each time.

  Open secrets.yaml.sample with nano or other text editor: nano hass-config/secrets.yaml.sample

  hostip: "<hostip>" # substitute your pi's LAN IP address  e.g., hostip: 192.168.0.31 
  configurator_url: "http://<hostip>:3218/" 
  nodered_url: "http://<hostip>:1880/"
  
  ha_db_url: "mysql://homeassistant:<ha_dbdatabasepassword>@<hostip>/ha_db?charset=utf8"
  

  <hostip>: Is your hosts IP address on the network.
  <ha_dbdatabasepassword> is the the value from your .env file. Edit these lines and exit after saving without the .sample suffix.

  You will have to make sure to remove the suffix .sample from these filenames or otherwise provide a .env and secrets.yaml of your own.

  If you happened to save and close the files without renaming, you can rename them with the command mv, i.e.:
  mv .env.sample .env and mv ~/ha-config/secrets.yaml.sample ~/ha-config/secrets.yaml.sample

• Copy project folder

• modify .env.sample and secrets.yaml.sample

• execute docker-compose

Now the easy part! Make sure you're in the correct directory (so that docker can find the docker-compose.yaml) cd ~/home-assistant/ docker compose up -d and attach yourself to the logs from any term whenever you'd like,`docker compose logs -f -t'

If you'd prefer to have the output (logs, errors, etc.) from the containers attached displayed in your terminal window, leave off the -d (detached) flag:
docker compose up

# Stop services only
docker compose stop

# Stop and remove containers, networks..
docker compose down

Depending on your Linux distribution, some of these applications may already be installed on the host system. To avoid conflicts, you will have to uninstall them first (e.g., sudo apt-get remove mosquitto)

• Copy project folder
• modify .env.sample and secrets.yaml.sample
• execute docker-compose

If you open a web browser on the pi (or other computer on the LAN) you should now (or shortly) be able to navigate into the Home Assistant webserver at 'http://:8123’ to start onboarding.

https://www.zigbee2mqtt.io/guide/usage/integrations/home_assistant.html#mqtt-discovery

Git is a command-line tool, used by programmers to share/submit their code changes to a version controlled repository, so that when a bug crops up, or a software team decides to tackle a problem via a different route, the 5 W's (who, what, when, where, and why) that surround the code base are readily observable, because each change has been documented. Github, as the name evokes, sprung up around that, and besides providing a easy, web-accessible UI, it aids collaborative development build by serving as ahas many tools and integrations useful for testing and building software. With all these various tools, it turns out that GitHub can be useful for than just code, it's a platform used for curated lists, demos of code snippets, sharing Animal Crossing: New Horizonds infographics, and even hosting websites.

You can! I created this repo for a few reasons:

• to make it easier for others to setup a Home Assistant, Nodered, MQTT, SQL server!
• so that replicating my setup in the future will be that much easier. The docker-compose setup scheme for Home Assistant from Jere's guide assumes that you have this skeleton created on your system. Rather than recreate it from scratch in the future, I instead created it within a GitHub repository.
• to learn (the best way for one to learn is to teach)

The beauty of setting up Home Assistant with Docker Compose is that it simplifies the installing, troubleshooting, and sharing of your setup because the bulk of the details are already baked in to docker-compose.yaml which builds the server environment. Rather than having to remember or document a slew of apt-get commands and multiple manual file changes, by using Compose, you store much of the installation procedures and configuration as code.

The reddit user luna87 put it well:

I would also recommend using docker-compose and git for version control... ...you can easily define your entire container stack as a single service and bring everything up / down / restart together with docker compose.

You can then use Git to version control all of it. If I ever needed to move my home assistant install, all I would need to do is install docker, docker compose and git. Git clone my Git repository and docker-compose start.

Particularly with a public repository, you must make sure that no secrets are uploaded when the backing up the Home Assistant configuration to GitHub. This would tantamount to posting one's passwords in a public forum. To prevent this, I've added a .gitignore file to ensure that the sensitive files used in production (.env and secrets.yaml) are not uploaded to a git repository. This means that you still need to find a safe place to backup your secrets file, even if in the future, like me, you decide to backup/share your Home Assistant configuration to GitHub.

• When you back up your setup, make sure to securely back up your secrets and passwords as well!

You will need to first stop and remove all docker containers and images

To stop all containers, you can execute the command:
docker stop $(docker ps -aq)
Before removing the containers in the next step, I would advise you to backup the folder containing your existing Home Assistant config, if you intend to use it again. After you've backed up any save stores and you're ready for a clean slate, simply type
docker rm $(docker ps -aq)

If your previous efforts with Docker are still plaguing you, there is a nuclear option: docker system prune --all --volumes
Make sure your /hass-config/ folder is backed up first, everything will be wiped from the docker volumes/directories.

Mark Watt has a great video, especially if one is installing these packages through Home Assistant OS, which has a built in manager for official add-ons.

Because git tracks content, not directories., I have included empty files named .keep to the leaf nodes of the (otherwise) empty directories, so that the structure is preserved within the git repository. Contrary to the name, they don't have to be kept, and can safely be either ignored or deleted.

Within a directory, type ls –l [file_name] (without the brackets)

I've modelled my backup script after that which user mwav3 posted to the Home Assistant community forum:

Many of these important files start with . and are often hidden by default in Windows, macOS, and Linux. When you backup the folders, make sure that you are viewing all files before selection and copying.

I make use of rsync, I first make sure the directories exist mkdir ~/backups/hassrsync -p
and make sure that my user:defaultgroup has full permissions to the hass-config folder (rsync had issues with hidden folders like .store, sync seemed to have permission issues without first recursively changing ownership of the directory and files within)
sudo chown -R pi: home/pi/<directory-being-backed-up>

The actual backup routine looks much like below:

sudo chown -R pi: ~/home-assistant
rsync -ab --backup-dir=old_`date +%F` --delete --exclude=old_* /home/pi/home-assistant /media/pi/thumbdrive-backup/hassrsync