Reproducible Riak Core Lite Tutorial with Nix

Introduction

Over the years I've created and recreated guides, posts and tutorials on how to setup an environment to create riak_core based applications.

Most of the repetitive work and troubleshooting is around the moving target that is a current Erlang/Elixir/Rebar3/Mix setup.

With this attempt I hope people will be able to setup and follow the guides with a reproducible environment that always reflects the one I had when I wrote the guide.

For that I will use Nix, to follow it you just need git and nix.

Follow instructions here to Install Nix if you haven't done that already.

Riak Core Lite with Erlang

Clone the Riak Core Lite Rebar3 Template

mkdir -p ~/.config/rebar3/templates
git clone https://github.com/riak-core-lite/rebar3_template_riak_core_lite.git ~/.config/rebar3/templates/rebar3_template_riak_core_lite

Enter a nix-shell with the needed tools:

nix-shell ~/.config/rebar3/templates/rebar3_template_riak_core_lite/shell.nix

Now your shell should have Erlang and rebar3 available, try it:

erlc -h
rebar3 help

Now let's create a new Riak Core Lite application, go to the folder where you want to store your new project and then:

Create the project:

rebar3 new rebar3_riak_core_lite name=ricor

Build it:

cd ricor
rebar3 release

Try it:

./_build/default/rel/ricor/bin/ricor console

(ricor@127.0.0.1)1> ricor:ping().

The output should look something like, the number will probably be different:

{pong,'ricor@127.0.0.1', 1324485858831130769622089379649131486563188867072}

With this environment you should be able to follow previous tutorials and guides like the Riak Core Tutorial and maybe the Little Riak Core Book.

Riak Core Lite with Elixir

I recommend you to follow Rkv: Step by Step Riak Core Lite Key Value Store Project

Clone the project:

git clone https://github.com/riak-core-lite/rkv.git

Enter a nix-shell with the needed tools:

cd rkv
nix-shell shell.nix

Now your shell should have Erlang, Elixir, rebar3 and mix available, try it:

erlc -h
rebar3 help
elixirc -h
mix --help

Fetch deps, compile test and run:

mix deps.get
mix compile
mix test
iex --name dev@127.0.0.1 -S mix run

Play with the API:

Rkv.get(:k1)

# {:error, :not_found}

Rkv.delete(:k1)

# :ok

Rkv.put(:k2, :v2)

# :ok

Rkv.get(:k2)

# {:ok, :v2}

Rkv.delete(:k2)

# :ok

Rkv.get(:k2)

# {:error, :not_found}

Rkv.put(:k2, :v2)

Rkv.get(:k2)

# {:ok, :v2}

You can follow the guide by switching to each tag in order: https://github.com/riak-core-lite/rkv/tags

I will try to keep the shell.nix files on both languages up to date from time to time to keep with major Erlang/Elixir versions, you can try to update the nix hash yourself and see if it still builds by following the instructions here: Nix Possible URL values

Have fun!