Update dind-jenkins example (#2)

Author: kangasta

examples/jenkins/dind-jenkins/README.md

@@ -2,16 +2,28 @@
 
 Note that by default each of the example docker compose configurations will create their own volumes for the data. This might not be what you want. In order to use the same volumes for every docker compose configuration, run docker compose with `-p` (or `--project-name`) option. This can also be done by setting `COMPOSE_PROJECT_NAME` environment variable:
 
-```bash
+```sh
 export COMPOSE_PROJECT_NAME=jenkins
 ```
 
 ## Jenkins image with Docker-in-Docker support
 
-In order to run Jenkins container with Docker-in-Docker support, `cd` into [dind-jenkins](./dind-jenkins/) directory and run `docker compose up`. See Dockerfile and docker compose.yml for the configuration details.
+To be able run Docker commands from inside the Jenkins container, we will need to install the Docker client. This can be done with a suitable Dockerfile:
 
-```bash
-cd dind-jenkins/
+```Dockerfile title="Dockerfile"
+--8<-- "examples/jenkins/dind-jenkins/Dockerfile"
+```
+
+When running this container, we will want to define ports and volumes. To do this, we will use a `docker-compose.yml` configuration:
+
+```yaml title="docker-compose.yml"
+--8<-- "examples/jenkins/dind-jenkins/docker-compose.yml"
+```
+
+These files are available in the repository that provides this website. In order to run Jenkins container with Docker-in-Docker support, `cd` into `examples/jenkins/dind-jenkins` directory and run `docker compose up`.
+
+```sh
+cd examples/jenkins/dind-jenkins
 
 # If you want to see logs in the current terminal
 docker compose up --build
@@ -22,8 +34,8 @@ docker compose up --build --detach
 
 The initial admin password can be easily printed with `docker compose exec`:
 
-```bash
+```sh
 docker compose exec jenkins cat /var/jenkins_home/secrets/initialAdminPassword
 ```
 
-In order to get started the suggested plugins are often good a starting point. If you are planning to create pipeline projects with stages running in on-demand Docker containers, you will also need [Docker Pipeline](https://plugins.jenkins.io/docker-workflow/) plugin. This can be installed through the [Manage Jenkins > Manage plugins](http://localhost:8080/pluginManager/available) menu.
+In order to get started with Jenkins, the suggested plugins are often good a starting point. If you are planning to create pipeline projects with stages running in on-demand Docker containers, you will also need [Docker Pipeline](https://plugins.jenkins.io/docker-workflow/) plugin. This can be installed through the [Manage Jenkins > Manage plugins](http://localhost:8080/pluginManager/available) menu.

examples/jenkins/dind-jenkins/docker-compose.yml

@@ -2,15 +2,15 @@ services:
   jenkins:
     build: .
     ports:
-    # Web user interface
-    - 8080:8080
-    # Java agents
-    - 50000:50000
+      # Web user interface
+      - 8080:8080
+      # Java agents
+      - 50000:50000
     volumes:
-    # Persistent volume for the Jenkins data
-    - "jenkins.data:/var/jenkins_home"
-    # Host systems docker socket
-    - "/var/run/docker.sock:/var/run/docker.sock"
+      # Persistent volume for the Jenkins data
+      - "jenkins.data:/var/jenkins_home"
+      # Host systems docker socket
+      - "/var/run/docker.sock:/var/run/docker.sock"
 
 volumes:
   jenkins.data: