Fast code deployments with Docker in Digital ocean

deployment.md

Deployment Steps:

1. Commit and push to GitHub.
2. Ansible connects to our servers, pulls latest master from GitHub.
3. Ansible touches the app’s uwsgi.ini file to trigger UWSGI to reload.

Supervisor configuration:

We are using Supervisor inside the Docker container to start the processes run by the container. Our supervisord.conf looks like the following:

[supervisord]
nodaemon=true

[program:uwsgi]
command = /usr/local/bin/uwsgi --touch-reload=/path/to/code/in/container/uwsgi.ini --ini /path/to/code/in/container/uwsgi.ini

For a quick code deploy,

We run a playbook that contains these tasks and takes only a few seconds to run:

- set_fact: host_volume="/path/to/code/on/host"
- name: Git pull the latest code
  git: repo=git@github.com:{{ org }}/{{ container }}.git
       dest={{ host_volume }}
       accept_hostkey=yes
       force=yes

- name: Gracefully reload uwsgi
  file: path={{ touch_file }} state=touch

For a full deploy

If we need to restart the entire container or update system packages, we can do a container deploy, which takes a few minutes, with these tasks:

- name: Add app dir if it doesn't yet exist
  file: path={{ host_volume }} owner=nobody group=docker recurse=yes state=directory
  sudo: yes
- name: Pull Docker image
  command: "{{ item }}"
  ignore_errors: yes
  with_items:
    - docker pull {{ org }}/{{ container }}
    - docker stop {{ container }}
    - docker rm {{ container }}
- name: Run Docker image with app volumes
  command:  docker run -d -P -v {{ host_volume }}:{{ container_volume }} --name={{ container }} {{ extra_params }} {{ org }}/{{ container }}