Docker deployment workflow with git

Question

What is the best way to deploy a docker container to a production environment?

• Add a Dockerfile to the git repository and run docker build on the production system
• Commit changes to a container with docker commit and push it to a private Docker repository and then pull it with docker pull to the production system.

Should I run docker commit even if I don't change the infrastructure but just the app code?

I hope my questions are clear.

Answer 1

I would say that in a production environment you just want to pull and run the last image(s) of your container(s).

So the idea of having a private registry is good, and your delivery pipeline would be :

1. Commit changes to your app or your Dockerfile(s)
2. CI takes changes, compile your app, build your new image(s), and push it to the registry
3. Pull new image(s) on the production
4. Run it !

On my side, I don't use docker commit, i prefer tags with docker build ... -t .... I only use commit when i debug a container with an interactive shell.

Answer 2

Ideally you would have some sort of registry server and your docker containers would be up there, your production environment would pull these in and use them. You shouldn't have to update the docker container when your app code changes, ADD /project in your Dockerfile and share it with --volumes-from to other containers. You app should independent from the containers altogether.

There are tools out there now like fig, which let you start up a development environment with docker containers. You would then take this further and deploy your app containers in a CoreOS cluster.

Here is what I have for my productAPI, this just ADDs the project code into the container.

You shouldn't have to change the Dockerfile all that much unless your system dependencies change for the project.

Dockerfile

FROM phusion/baseimage
MAINTAINER Alex Goretoy <[email protected]>

ENV DEBIAN_FRONTEND noninteractive

ENV PRODUCT_API_PATH /opt/product_api

RUN mkdir -p $PRODUCT_API_PATH/

ADD . $PRODUCT_API_PATH/

RUN $PRODUCT_API_PATH/setup.sh

EXPOSE 8080

CMD python $PRODUCT_API_PATH/manage.py runserver

setup.sh

#!/bin/bash

apt-get update

apt-get install -y git \
    wget \
    openssl \
    libssl-dev \
    libffi-dev \
    python-pip \
    python2.7-dev \
    postgresql-9.3 \
    libpq-dev

apt-get update

apt-get install -y libcurl4-openssl-dev

apt-get update

wget https://bootstrap.pypa.io/ez_setup.py -O - | python

pip install -r $PRODUCT_API_PATH/requirements.txt

# Clean up APT when done.
apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*