Rails guide upgrade (part 2) (#22114)

## Description

This PR has two goals. First of all it continues work that has been done
in #21559. Besides this, and this is more significant, I tried to
improve the structure of the documentation that is currently used for
different language-specific guides like
[PHP](https://docs.docker.com/guides/php/configure-ci-cd/),
[Go](https://docs.docker.com/guides/golang/),
[Python](https://docs.docker.com/guides/python/) and others, including,
of course, Ruby itself.

Each of these guides currently has a [Configure
CI/CD](https://docs.docker.com/guides/python/configure-ci-cd/) section.
Inside this section there is a GitHub Actions workflow example that has
nothing in common with a CI/CD pipeline. It's just an example of how to
build and push an image to a Docker Hub registry. We should be clear in
our documentation and not mislead our users. This was the main reason
why I renamed this section to "Automate your builds with GitHub
Actions". I also updated the content of this section to reflect the new
name and to make it more clear what the user can expect from this guide.
I suggest the same be done for all other language-specific guides.

Besides this, I changed the order of the sections in the Ruby guide. The
"Develop your app" section has been moved down to the bottom of the
guide. This makes more sense to me because of two reasons:

1. It is more important to start using Docker Hub right after you added
the Dockerfile to your project (section number one in all
language-specific guides).

2. I can hardly imagine anybody using Docker to run the app locally for
development purposes (at least for Ruby). What is really essential and
useful is to know how to run services, that are required by your app,
like a database, a cache server, or a local LLM. This is why the
"Develop your app" section should be rewritten to explain how to run the
infrastructure services that are required by the app and not the app
itself.

Below there are screenshots reflecting the changes that have been made
in this PR.

**Before**
<img width="1512" alt="Screenshot 2025-02-27 at 11 26 39"
src="https://github.com/user-attachments/assets/1ca06aea-ffeb-4efb-a14d-27254d2a2110"
/>

**After** 
<img width="1512" alt="Screenshot 2025-02-27 at 11 26 01"
src="https://github.com/user-attachments/assets/7abbe8b7-d1b3-480f-8105-49f967b51e47"
/>

## Related issues or tickets

#21559

## Reviews

- [x] Technical review
- [x] Editorial review
- [ ] Product review

Author: igor-alexandrov

content/guides/ruby/_index.md

@@ -12,15 +12,16 @@ aliases:
   - /language/ruby/
   - /guides/language/ruby/
 languages: [ruby]
+tags: [frameworks]
 params:
   time: 20 minutes
 ---
 
 The Ruby language-specific guide teaches you how to containerize a Ruby on Rails application using Docker. In this guide, you’ll learn how to:
 
 - Containerize and run a Ruby on Rails application
+- Configure a GitHub Actions workflow to build and push a Docker image to Docker Hub
 - Set up a local environment to develop a Ruby on Rails application using containers
-- Configure a CI/CD pipeline for a containerized Ruby on Rails application using GitHub Actions
 - Deploy your containerized Ruby on Rails application locally to Kubernetes to test and debug your deployment
 
 Start by containerizing an existing Ruby on Rails application.

content/guides/ruby/configure-ci-cd.md

@@ -0,0 +1,111 @@
+---
+title: Automate your builds with GitHub Actions
+linkTitle: Automate your builds with GitHub Actions
+weight: 20
+keywords: ci/cd, github actions, ruby, flask
+description: Learn how to configure CI/CD using GitHub Actions for your Ruby on Rails application.
+aliases:
+  - /language/ruby/configure-ci-cd/
+  - /guides/language/ruby/configure-ci-cd/
+  - /guides/ruby/configure-ci-cd/
+---
+
+## Prerequisites
+
+Complete all the previous sections of this guide, starting with [Containerize a Ruby on Rails application](containerize.md). You must have a [GitHub](https://github.com/signup) account and a [Docker](https://hub.docker.com/signup) account to complete this section.
+
+If you didn't create a [GitHub repository](https://github.com/new) for your project yet, it is time to do it. After creating the repository, don't forget to [add a remote](https://docs.github.com/en/get-started/getting-started-with-git/managing-remote-repositories) and ensure you can commit and [push your code](https://docs.github.com/en/get-started/using-git/pushing-commits-to-a-remote-repository#about-git-push) to GitHub.
+
+1. In your project's GitHub repository, open **Settings**, and go to **Secrets and variables** > **Actions**.
+
+2. Under the **Variables** tab, create a new **Repository variable** named `DOCKER_USERNAME` and your Docker ID as a value.
+
+3. Create a new [Personal Access Token (PAT)](/manuals/security/for-developers/access-tokens.md#create-an-access-token) for Docker Hub. You can name this token `docker-tutorial`. Make sure access permissions include Read and Write.
+
+4. Add the PAT as a **Repository secret** in your GitHub repository, with the name
+   `DOCKERHUB_TOKEN`.
+
+## Overview
+
+GitHub Actions is a CI/CD (Continuous Integration and Continuous Deployment) automation tool built into GitHub. It allows you to define custom workflows for building, testing, and deploying your code when specific events occur (e.g., pushing code, creating a pull request, etc.). A workflow is a YAML-based automation script that defines a sequence of steps to be executed when triggered. Workflows are stored in the `.github/workflows/` directory of a repository.
+
+In this section, you'll learn how to set up and use GitHub Actions to build your Docker image as well as push it to Docker Hub. You will complete the following steps:
+
+1. Define the GitHub Actions workflow.
+2. Run the workflow.
+
+## 1. Define the GitHub Actions workflow
+
+You can create a GitHub Actions workflow by creating a YAML file in the `.github/workflows/` directory of your repository. To do this use your favorite text editor or the GitHub web interface. The following steps show you how to create a workflow file using the GitHub web interface.
+
+If you prefer to use the GitHub web interface, follow these steps:
+
+1. Go to your repository on GitHub and then select the **Actions** tab.
+
+2. Select **set up a workflow yourself**.
+
+   This takes you to a page for creating a new GitHub Actions workflow file in
+   your repository. By default, the file is created under `.github/workflows/main.yml`, let's change it name to `build.yml`.
+
+If you prefer to use your text editor, create a new file named `build.yml` in the `.github/workflows/` directory of your repository.
+
+Add the following content to the file:
+
+```yaml
+name: Build and push Docker image
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build_and_push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ vars.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          push: true
+          tags: ${{ vars.DOCKER_USERNAME }}/${{ github.event.repository.name }}:latest
+```
+
+Each GitHub Actions workflow includes one or several jobs. Each job consists of steps. Each step can either run a set of commands or use already [existing actions](https://github.com/marketplace?type=actions). The action above has three steps:
+
+1. [**Login to Docker Hub**](https://github.com/docker/login-action): Action logs in to Docker Hub using the Docker ID and Personal Access Token (PAT) you created earlier.
+
+2. [**Set up Docker Buildx**](https://github.com/docker/setup-buildx-action): Action sets up Docker [Buildx](https://github.com/docker/buildx), a CLI plugin that extends the capabilities of the Docker CLI.
+
+3. [**Build and push**](https://github.com/docker/build-push-action): Action builds and pushes the Docker image to Docker Hub. The `tags` parameter specifies the image name and tag. The `latest` tag is used in this example.
+
+## 2. Run the workflow
+
+Let's commit the changes, push them to the `main` branch. In the workflow above, the trigger is set to `push` events on the `main` branch. This means that the workflow will run every time you push changes to the `main` branch. You can find more information about the workflow triggers [here](https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows).
+
+Go to the **Actions** tab of you GitHub repository. It displays the workflow. Selecting the workflow shows you the breakdown of all the steps.
+
+When the workflow is complete, go to your [repositories on Docker Hub](https://hub.docker.com/repositories). If you see the new repository in that list, it means the GitHub Actions workflow successfully pushed the image to Docker Hub.
+
+## Summary
+
+In this section, you learned how to set up a GitHub Actions workflow for your Ruby on Rails application.
+
+Related information:
+
+- [Introduction to GitHub Actions](/guides/gha.md)
+- [Docker Build GitHub Actions](/manuals/build/ci/github-actions/_index.md)
+- [Workflow syntax for GitHub Actions](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions)
+
+## Next steps
+
+In the next section, you'll learn how you can develop your application using containers.
+

content/guides/ruby/configure-github-actions.md

@@ -24,7 +24,7 @@ Starting from Rails 7.1 [Docker is supported out of the box](https://guides.ruby
 
 If you have an existing Rails application, you will need to create the Docker assets manually. Unfortunately `docker init` command does not yet support Rails. This means that if you are working with Rails, you'll need to copy Dockerfile and other related configurations manually from the examples below.
 
-## Initialize Docker assets
+## 1. Initialize Docker assets
 
 Rails 7.1 generates multistage Dockerfile out of the box, below is an example of such file generated from a Rails template.
 
@@ -232,7 +232,7 @@ To learn more about the files, see the following:
 - [compose.yaml](/reference/compose-file/_index.md)
 - [docker-entrypoint](/reference/dockerfile/#entrypoint)
 
-## Run the application
+## 2. Run the application
 
 To run the application, run the following command in a terminal inside the application's directory.
 
@@ -244,7 +244,7 @@ Open a browser and view the application at [http://localhost:3000](http://localh
 
 In the terminal, press `ctrl`+`c` to stop the application.
 
-### Run the application in the background
+## 3. Run the application in the background
 
 You can run the application detached from the terminal by adding the `-d`
 option. Inside the `docker-ruby-on-rails` directory, run the following command
@@ -278,5 +278,4 @@ Related information:
 
 ## Next steps
 
-In the next section, you'll learn how you can develop your application using
-containers.
+In the next section, you'll take a look at how to set up a CI/CD pipeline using GitHub Actions.

content/guides/ruby/containerize.md

@@ -24,7 +24,7 @@ In your `docker-ruby-on-rails` directory, create a file named
 `docker-ruby-on-rails-kubernetes.yaml`. Open the file in an IDE or text editor and add
 the following contents. Replace `DOCKER_USERNAME/REPO_NAME` with your Docker
 username and the name of the repository that you created in [Configure CI/CD for
-your Ruby on Rails application](configure-ci-cd.md).
+your Ruby on Rails application](configure-github-actions.md).
 
 ```yaml
 apiVersion: apps/v1
@@ -68,7 +68,7 @@ In this Kubernetes YAML file, there are two objects, separated by the `---`:
   you'll get just one replica, or copy of your pod. That pod, which is
   described under `template`, has just one container in it. The
   container is created from the image built by GitHub Actions in [Configure CI/CD for
-  your Ruby on Rails application](configure-ci-cd.md).
+  your Ruby on Rails application](configure-github-actions.md).
 - A NodePort service, which will route traffic from port 30001 on your host to
   port 8001 inside the pods it routes to, allowing you to reach your app
   from the network.

content/guides/ruby/deploy.md

@@ -1,7 +1,7 @@
 ---
 title: Use containers for Ruby on Rails development
 linkTitle: Develop your app
-weight: 20
+weight: 40
 keywords: ruby, local, development
 description: Learn how to develop your Ruby on Rails application locally.
 aliases:
@@ -200,4 +200,4 @@ Related information:
 
 ## Next steps
 
-In the next section, you'll take a look at how to set up a CI/CD pipeline using GitHub Actions.
+In the next section, you'll learn how you can locally test and debug your workloads on Kubernetes before deploying.