Ansible for Docker Deployment
Downloading Docker Images
See docker_image Module.
---
- hosts: test
tasks:
- name: Pull Docker Image
docker_image:
name: hello-world
source: pull
state: present
Running the playbook results in an error message that the docker python library is missing:
ansible-playbook docker.yml
PLAY [test] ********************************************************************************************************
TASK [Gathering Facts] ********************************************************************************************************************
ok: [192.168.2.111]
TASK [Pull Docker Image] ********************************************************************************************************************
fatal: [192.168.2.111]: FAILED! => {"changed": false, "msg": "Failed to import the required Python library (Docker SDK for Python: docker (Python >= 2.7) or docker-py (Python 2.6)) on minion's Python /usr/bin/python3. Please read module documentation and install in the appropriate location. If the required library is installed, but Ansible is using the wrong Python interpreter, please consult the documentation on ansible_python_interpreter, for example via `pip install docker` or `pip install docker-py` (Python 2.6). The error was: No module named 'docker'"}
PLAY RECAP *********************************************************************************************************
192.168.2.111 : ok=1 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
I will try to solve this by running pip install docker on my host system. If this works, this step has to be included in the docker playbook.
During handling of the above exception, another exception occurred: Read timed out. Increasing the timeout with
pip --default-timeout=1000 install docker
Running Docker Container
See docker_container Module.
This plugin is part of the community.general collection (version 1.3.0). To install it use:
ansible-galaxy collection install community.general
Example I
To use it in a playbook, specify: community.general.docker_container:
Ansible
---
- hosts: test
tasks:
- name: Setup a Nginx Docker Container
community.general.docker_container:
name: ingress
image: nginx:stable-alpine
networks:
- name: gateway
state: started
restart_policy: unless-stopped
ports:
- "80:80"
- "443:443"
volumes:
- /opt/docker-ingress/configuration/conf.d:/etc/nginx/conf.d
- /opt/docker-ingress/configuration/nginx.conf:/etc/nginx/nginx.conf
- /opt/test-static/public:/opt/test-static/public
- /opt/downloads:/opt/downloads
This is the Ansible version of the Docker-Compose NGINX Example - which is really interesting... you can actually migrate from docker-compose to Ansible. Did not think of that before:
Docker-Compose
version: "3.8"
services:
ingress:
image: nginx:stable-alpine
container_name: ingress
networks:
- gateway
ports:
- "80:80"
- "443:443"
restart: unless-stopped
volumes:
- /opt/docker-ingress/configuration/conf.d:/etc/nginx/conf.d
- /opt/docker-ingress/configuration/nginx.conf:/etc/nginx/nginx.conf
- /opt/test-static/public:/opt/test-static/public
- /opt/downloads:/opt/downloads
networks:
gateway: {}
Example II
I now want to rebuild the web app template with Docker that I build before by installing NGINX directly on the host system:
---
- hosts: test
tasks:
- name: Setup a Nginx Docker Container
docker_container:
name: ingress
image: nginx:stable-alpine
state: started
restart_policy: unless-stopped
ports:
- "80:80"
- "443:443"
volumes:
- /opt/test-static/nginx/nginx.conf:/etc/nginx/nginx.conf
- /opt/test-static/nginx/conf.d/:/etc/nginx/conf.d
- /opt/test-static/nginx/ssl/:/etc/nginx/ssl
- /opt/test-static/public/:/opt/test-static/public