<!--[metadata]>
+++
title = "Dockerizing a Riak service"
description = "Build a Docker image with Riak pre-installed"
keywords = ["docker, example, package installation, networking,  riak"]
[menu.main]
parent = "smn_apps_servs"
+++
<![end-metadata]-->

# Dockerizing a Riak service

The goal of this example is to show you how to build a Docker image with
Riak pre-installed.

## Creating a Dockerfile

Create an empty file called `Dockerfile`:

    $ touch Dockerfile

Next, define the parent image you want to use to build your image on top
of. We'll use [Ubuntu](https://registry.hub.docker.com/_/ubuntu/) (tag:
`trusty`), which is available on [Docker Hub](https://hub.docker.com):

    # Riak
    #
    # VERSION       0.1.1
    
    # Use the Ubuntu base image provided by dotCloud
    FROM ubuntu:trusty
    MAINTAINER Hector Castro hector@basho.com

After that, we install the curl which is used to download the repository setup
script and we download the setup script and run it.

    # Install Riak repository before we do apt-get update, so that update happens
    # in a single step
    RUN apt-get install -q -y curl && \
        curl -sSL https://packagecloud.io/install/repositories/basho/riak/script.deb | sudo bash

Then we install and setup a few dependencies:

 - `supervisor` is used manage the Riak processes
 - `riak=2.0.5-1` is the Riak package coded to version 2.0.5

<!-- -->

    # Install and setup project dependencies
    RUN apt-get update && \
        apt-get install -y supervisor riak=2.0.5-1

    RUN mkdir -p /var/log/supervisor
    
    RUN locale-gen en_US en_US.UTF-8
    
    COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf

After that, we modify Riak's configuration:

    # Configure Riak to accept connections from any host
    RUN sed -i "s|listener.http.internal = 127.0.0.1:8098|listener.http.internal = 0.0.0.0:8098|" /etc/riak/riak.conf
    RUN sed -i "s|listener.protobuf.internal = 127.0.0.1:8087|listener.protobuf.internal = 0.0.0.0:8087|" /etc/riak/riak.conf

Then, we expose the Riak Protocol Buffers and HTTP interfaces:

    # Expose Riak Protocol Buffers and HTTP interfaces
    EXPOSE 8087 8098

Finally, run `supervisord` so that Riak is started:

    CMD ["/usr/bin/supervisord"]

## Create a supervisord configuration file

Create an empty file called `supervisord.conf`. Make
sure it's at the same directory level as your `Dockerfile`:

    touch supervisord.conf

Populate it with the following program definitions:

    [supervisord]
    nodaemon=true
    
    [program:riak]
    command=bash -c "/usr/sbin/riak console"
    numprocs=1
    autostart=true
    autorestart=true
    user=riak
    environment=HOME="/var/lib/riak"
    stdout_logfile=/var/log/supervisor/%(program_name)s.log
    stderr_logfile=/var/log/supervisor/%(program_name)s.log

## Build the Docker image for Riak

Now you should be able to build a Docker image for Riak:

    $ docker build -t "<yourname>/riak" .

## Next steps

Riak is a distributed database. Many production deployments consist of
[at least five nodes](
http://basho.com/why-your-riak-cluster-should-have-at-least-five-nodes/).
See the [docker-riak](https://github.com/hectcastro/docker-riak) project
details on how to deploy a Riak cluster using Docker and Pipework.