proxy-stopping.yaml

Overview

This file is an Ansible playbook snippet designed to stop and remove Docker containers and associated volumes related to a proxy service. It achieves this by executing a shell command that runs docker compose down -v within a specified directory. This operation is typically used to cleanly shut down containerized services and remove their volumes, ensuring no residual data or running containers remain.

Detailed Explanation

Playbook Task: Compose down

• name: Compose down

• ansible.builtin.shell: This Ansible module runs shell commands on the target host.

• Parameters:

  • chdir: Specifies the directory in which to run the shell command. It uses the variable PROXY_DIR to define the path where the Docker Compose project is located.

  • cmd: The shell command executed, docker compose down -v.

Purpose of the Command

• docker compose down: Stops and removes containers, networks, and default volumes created by docker compose up.

• -v: Additionally removes named volumes declared in the volumes section of the Compose file.

Usage Example

If the variable PROXY_DIR is set to /home/user/proxy, the task executes:

cd /home/user/proxy
docker compose down -v

This stops the proxy service containers defined in the docker-compose.yml located inside /home/user/proxy and removes the associated Docker volumes.

Variables

• PROXY_DIR: Must be defined elsewhere in the playbook or inventory. It points to the directory where the proxy Docker Compose project is stored.

Implementation Details

• The playbook uses the ansible.builtin.shell module instead of ansible.builtin.command because docker compose down -v is a shell command that may require shell features such as environment variable expansion or command chaining.

• By specifying chdir, the playbook ensures the command runs in the correct directory context, where the docker-compose.yml file resides.

• The removal of volumes (-v) is critical for ensuring a clean state, preventing leftover data from persisting between deployments or restarts.

Interaction with Other Parts of the System

• This file is typically part of a larger deployment or teardown process for proxy services.

• The variable PROXY_DIR is expected to be set externally, possibly by another playbook or inventory configuration managing the proxy service lifecycle.

• It interacts indirectly with Docker and the Docker Compose toolset installed on the host.

• It is likely invoked after the proxy service has been running or during a cleanup phase to stop and remove proxy containers and volumes.

• The stopped containers and removed volumes will impact any services depending on the proxy, which must be accounted for in orchestration or dependency management.

Visual Diagram

flowchart TD
A[Start Task: Compose down] --> B[Change directory to PROXY_DIR]
B --> C[Run shell command: docker compose down -v]
C --> D[Stop and remove containers]
C --> E[Remove volumes]
D --> F[Proxy containers stopped]
E --> G[Proxy volumes removed]