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The article describes the process of setting up an application for release on a remote server. For such a not easy business in the world of Elixir, there are two good projects, the first is Distillery , which makes the application build and the second is Edeliver , which allows hot-swappable code. Below are the basic instructions for using these two libraries on the example of the simplest Elixir application. As well as the article will tell how to improve deploy through the use of docker containers.

Distillery

Distillery designed to automate the generation of releases of Elixir projects! He is an Exrm heir from the same author. Very easy to use.

The first thing you need to add distillery in the project. And then run mix deps.get .

 def application do [ mod: {Single, []}, applications: [:logger, :cowboy, :plug] ] end defp deps do [{:cowboy, "~> 1.1.2"}, {:plug, "~> 1.3.0"}, {:distillery, "~> 1.0"}] end 

To create a configuration file for a distillery , the following command should be executed in the project directory:

 mix release.init 

This command will create a rel directory with the config.exs file. Distillery has a large number of customizable parameters . The file generated automatically came right away.

In order to make a build application for deployment in "combat" mode, you must run the following command:

 MIX_ENV=prod mix release --env=prod 

This command will create a _build/prod/rel/<name>/releases/<version>/<name>.tar.gz with the compiled application. Further, this archive must be delivered to the prod. server where you need to unzip and run the application. This can be done using a simple shell script, but this is not the best option, since it will be downtime.

 #!/bin/sh REMOTE_USER="www" REMOTE_HOST="host" APP_NAME="single" APP_FOLDER="/home/$REMOTE_USER/$APP_NAME" SERVER=$REMOTE_USER@$REMOTE_HOST echo "Enter the version of the application" read VERSION if !(ssh $SERVER "[ -d $APP_FOLDER/tmp/ ]") then echo "Preparing directory structure" ssh $SERVER "mkdir -p $APP_FOLDER/tmp/" fi echo "Copying release to server in $APP_FOLDER" scp _build/prod/rel/$APP_NAME/releases/$VERSION/$APP_NAME.tar.gz $SERVER:$APP_FOLDER/tmp/ echo "Stopping the old version" ssh $SERVER "cd $APP_FOLDER && bin/$APP_NAME stop" echo "Extracting archive with release" ssh $SERVER "cd $APP_FOLDER/tmp/ && tar -xzf $APP_NAME.tar.gz -C $APP_FOLDER" echo "Running the new version" ssh $SERVER "cd $APP_FOLDER && PORT=80 bin/$APP_NAME start" 

It remains only to check the availability of the offer.

 curl -i http://host HTTP/1.1 200 OK server: Cowboy date: Thu, 09 Feb 2017 11:28:08 GMT content-length: 9 cache-control: max-age=0, private, must-revalidate content-type: text/plain; charset=utf-8 Single v1 

You can simplify the delivery of the application on the prod. server using Edeliver .

Edeliver

Edeliver is essentially an add-on written on Elixir over a set of bash scripts that can build and deploy Elixir and Erlang applications, as well as perform hot code updates.

The first step is to add edeliver to the project dependencies. And then run mix deps.get .

 def application do [ mod: {Single, []}, applications: [:logger, :cowboy, :plug, :edeliver] ] end defp deps do [{:cowboy, "~> 1.1.2"}, {:plug, "~> 1.3.0"}, {:distillery, "~> 1.0"}, {:edeliver, "~> 1.4.2"}] end 

All settings for Edeliver are stored in a .deliver/config file. In it, you can specify all sorts of environments. For example BUILD, STAGING and PRODUCTION.

 APP="single" BUILD_HOST="host" BUILD_USER="www" BUILD_AT="/home/www/single/tmp" PRODUCTION_HOSTS="host" PRODUCTION_USER="www" DELIVER_TO="/home/www/single" 

In order to make a build application for deployment in "combat" mode, you must run the following command:

 env MIX_ENV=prod mix edeliver build release 

Then, to deliver the build to the right environment (in this case, production), you need to do:

 mix edeliver deploy release to production --version=0.1.0 

This command will only download the collected release to a remote server, but will not launch the application itself.
To launch an application, use the following command:

 mix edeliver start production 

If you did a build in a non-production environment, you can get a non-working application. This is due to the fact that when assembling an application, NIFs (native implemented functions) are used, which on different machines may be ... different.

It remains only to check the availability of the offer.

 curl -i http://host HTTP/1.1 200 OK server: Cowboy date: Thu, 09 Feb 2017 11:28:08 GMT content-length: 9 cache-control: max-age=0, private, must-revalidate content-type: text/plain; charset=utf-8 Single v2 

A bit about Docker and Distillery

I have nothing to tell here, better read the excellent translation from Wunsh of this article http://teamon.eu/2017/deploying-phoenix-to-production-using-docker/

Heroku

Deploying Elixir applications on Heroku is very simple, all you need is to add a buildpack to an existing application.

 heroku buildpacks:set https://github.com/HashNuke/heroku-buildpack-elixir 

Or create a new application with this buildpack.

 heroku create --buildpack "https://github.com/HashNuke/heroku-buildpack-elixir.git" 

This buildpack can be configured using the example from the official repository .

Then, as you are used to, just do:

 git push heroku master 

Conclusion

If you are interested in the functional programming language Elixir or you are just sympathetic, then I advise you to join the Telegram channel https://telegram.me/proelixir about Elixir.

In the domestic Elixir community, a single platform begins to appear in the face of the Wunsh.ru project. Now the project has a thematic newsletter, in which there is nothing illegal, once a week will receive a letter with a collection of articles about Elixir in Russian.

Literature

http://bitwalker.org/posts/2016-07-21-distillery-vs-exrm-vs-relx/
https://shovik.com/blog/6-deploying-phoenix-apps-for-rails-developers
https://github.com/bitwalker/distillery
https://github.com/boldpoker/edeliver
https://github.com/HashNuke/heroku-buildpack-elixir
http://blog.plataformatec.com.br/2016/06/deploying-elixir-applications-with-edeliver/