Create a Mix archive with library dependencies

Hello,

I am currently building a Mix archive in Elixir. I have multiple library dependencies. here my mix.exs

defmodule Zenaton.Mixfile do
    use Mix.Project

    def version, do: "1.0.0"
    def project do
        [
            app: :zenaton,
            version: version(),
            elixir: "~> 1.4",
            build_embedded: Mix.env == :prod,
            start_permanent: Mix.env == :prod,
            name: "zenaton",
            aliases: aliases(),
            deps: deps()
        ]
    end

    # Configuration for the OTP application
    #
    # Type "mix help compile.app" for more information
    def application do
        # Specify extra applications you'll use from Erlang/Elixir
        [
            extra_applications: [:amqp, :porcelain, :logger, :cowboy, :plug, :httpoison, :dotenv],
            mod: {Zenaton.Application, []}
        ]
    end

    defp deps do
        [
            {:amqp, "~> 0.3.0"},
            {:cowboy, "~> 1.1"},
            {:dotenv, "~> 2.0.0"},
            {:httpoison, "~> 0.13.0"},
            {:plug, "~> 1.4"},
            {:poison, "~> 3.1"},
            {:porcelain, "~> 2.0"},
            {:uuid, "~> 1.1"}
        ]
    end

    defp aliases do
        [
            build: [ &build_releases/1]
        ]
    end

    defp build_releases(_) do
        Mix.Tasks.Compile.run([])
        Mix.Tasks.Archive.Build.run([])
        Mix.Tasks.Archive.Build.run(["--output=zenaton.ez"])

        archives = "./zenaton_archives"
        File.rename("zenaton.ez", "#{archives}/zenaton.ez")
        File.rename("zenaton-#{version()}.ez", "#{archives}/zenaton-#{version()}.ez")
    end
end

I can install very easily this archive by doing: mix archive.install zenaton.ez and when I’m launching my task command with mix zenaton.listen. I have this error:slight_smile:

** (FunctionClauseError) no function clause matching in Mix.raise/1
(mix) lib/mix.ex:275: Mix.raise({:error, {:amqp, {‘no such file or directory’, ‘amqp.app’}}})
(mix) lib/mix/task.ex:294: Mix.Task.run_task/3
(mix) lib/mix/cli.ex:58: Mix.CLI.run_task/2
(elixir) lib/code.ex:370: Code.require_file/2

It seems that the archive is not built with amqp dependencies.

In my run/1 function in mix task, I added Application.ensure_all_started(:zenaton) to load the dependencies. But it doesn’t help

The first question that comes to mind is why you want to have such an archive with dependencies. Archives should mostly be used for extending Mix with plugins and not much else.

Ok, I would like to build a global mix task that is quite similar to mix phoenix.server : it will launch a local HTTP server and a rabbitMQ connection, that’s why I’m using AMQP. Do you think it’s a problem ?

Why would that need to be global? Couldn’t it be added by a dependency in the consuming project? phx.server is not a global, it is defined in phoenix. The only global is phx.new.

1 Like

Ok So I am going to sum up what I would like to do and you may have an idea to solve my problem:

I would like to create a global CLI that can be installed on every machine that has Elixir installed. This CLI will have a command that will start a local HTTP server and a rabbitMQ connection.

How will you proceed?

I’d build an escript, so you’d only need erlang on the machine executing the cli.

3 Likes

Is this meant to be a tool used for development on other elixir projects? Then I would do what @jeremyjh said and put it in it’s own standalone project as a Mix.Task with its own set of dependencies as needed. Then in the other projects you want to use it on you would just add it to your mix dependencies and deps.get. As mentioned, this is how phx.server and ecto.create and stuff work: they come from the phoenix and ecto dependencies included in the project.

If it’s meant to be a standalone tool that is used outside of the context of an existing Elixir project then I would do like @LostKobrakai and create an escript. Then you can put this escript into the $PATH on the different machines and run it just like any other command line tool.

If it’s meant to a full on application (as in not really just a tool) then you may want to consider using Distillery and creating a full release. That way it will come packaged with the erlang runtime and you’d deploy it like a production application.

3 Likes

Archives do not include dependencies because archives are loaded into the same VM as Mix and the users application when they run their application through Mix. If archives were to include dependencies they would conflict with the user’s dependencies since you can only have one instance of an application loaded. So for example if the user depended on poison your archive would break them since you load poison yourself.

Archives should only be used when you need to interact with or extend Mix. If you just want to start an HTTP server it doesn’t sound like it would interact Mix so it should probably be an archive instead.

2 Likes

Should this end “it should probably be an escript instead”?

Yes, thanks for the catch.