Skip to content

Container Development

Purpose: This document will outline the general workflow of using Visual Studio Code to author and update custom containers and push them to a container registry hosted in Gitea. This will be referencing the git-repo-updater project throughout.

Assumptions

This document assumes you are authoring the containers in Microsoft Windows, and does not include the fine-tuning necessary to work in Linux or MacOS environments. You are on your own if you want to author containers in Linux.

Install Visual Studio Code

The management of the Gitea repositories, Dockerfile building, and pushing container images to the Gitea container registry will all involve using just Visual Studio Code. You can download Visual Studio Code from this direct download link.

Configure Required Docker Extensions

You will need to locate and install the Dev Containers, Docker, and WSL extensions in Visual Studio Code to move forward. This may request that you install Docker Desktop onto your computer as part of the installation process. Proceed to do so, then when the Docker "Engine" is running, you can proceed to the next step.

Warning

You need to have Docker Desktop "Engine" running whenever working with containers, as it is necessary to build the images. VSCode will complain if it is not running.

Add Gitea Container Registry

At this point, we need to add a registry to Visual Studio Code so it can proceed with pulling down the repository data.

  • Click the Docker icon on the left-hand toolbar
  • Under "Registries", click "Connect Registry..."
  • In the dropdown menu that appears, click "Generic Registry V2"
  • Enter https://git.bunny-lab.io/container-registry
  • Registry Username: nicole.rappe
  • Registry Password or Personal Access Token: Personal Access API Token You Generated in Gitea
  • You will now see a sub-listing named "Generic Registry V2"
  • If you click the dropdown, you will see "https://git.bunny-lab.io/container-registry"
  • Under this section, you will see any containers in the registry that you have access to, in this case, you will see container-registry/git-repo-updater

Add Source Control Repository

Now it is time to pull down the repository where the container's core elements are stored on Gitea.

  • Click the "Source Control" button on the left-hand menu then click the "Clone Repository" button
  • Enter https://git.bunny-lab.io/container-registry/git-repo-updater.git
  • Click the dropdown menu option "Clone from URL" then choose a location to locally store the repository on your computer
  • When prompted with "Would you like to open the cloned repository", click the "Open" button

Making Changes

You will be presented with four files in this specific repository. .env, docker-compose.yml, Dockerfile, and repo_watcher.sh

  • .env is the environment variables passed to the container to tell it which ntfy server to talk to, which credentials to use with Gitea, and which repositories to download and push into production servers
  • docker-compose.yml is an example docker-compose file that can be used in Portainer to deploy the server along with the contents of the .env file
  • Dockerfile is the base of the container, telling docker what operating system to use and how to start the script in the container
  • repo_watcher.sh is the script called by the Dockerfile which loops checking for updates in Gitea repositories that were configured in the .env file

Push to Repository

When you make any changes, you will need to first commit them to the repository

  • Save all of the edited files
  • Click the "Source Control" button in the toolbar
  • Write a message about what you changed in the commit description field
  • Click the "Commit" button
  • Click the "Sync Changes" button that appears
  • You may be presented with various dialogs, just click the equivalant of "Yes/OK" to each of them

Build the Dockerfile

At this point, we need to build the dockerfile, which takes all of the changes and packages it into a container image

  • Navigate back to the file explorer inside of Visual Studio Code
  • Right-click the Dockerfile, then click "Build Image..."
  • In the "Tag Image As..." window, type in git.bunny-lab.io/container-registry/git-repo-updater:latest
  • When you navigate back to the Docker menu, you will see a new image appear under the "Images" section
  • You should see something similar to "Latest - X Seconds Ago` indicating this is the image you just built
  • Delete the older image(s) by right-clicking on them and selecting "Remove..."
  • Push the image to the container registry in Gitea by right-clicking the latest image, and selecting "Push..."
  • In the dropdown menu that appears, enter git.bunny-lab.io/container-registry/git-repo-updater:latest
    • You can confirm if it was successful by navigating to the Gitea Container Webpage and seeing if it says "Published Now" or "Published 1 Minute Ago"

CRLF End of Line Sequences

When you are editing files in the container's repository, you need to ensure that Visual Studio Code is editing that file in "LF" mode and not "CRLF". You can find this toggle at the bottom-right of the VSCode window. Simply clicking on the letters "CRLF" will let you toggle the file to "LF". If you do not make this change, the container will misunderstand the dockerfile and/or scripts inside of the container and have runtime errors.

Deploy the Container

You can now use the .env file along with the docker-compose.yml file inside of Portainer to deploy a stack using the container you just built / updated.