Hello,
I’m trying for my first time to make a flake on one of my personnal project which is an Elixir discord bot.
The goal is to have a flake at the root of my project to be able to:
- Have a dev shell easy to deploy on my work machines.
- Have a derivation to use my app on some of my nixOs configuration machine and easily deploy my app as a service.
There is my work-in-progress flake:
{
description = "Flake for running a dev env and derivation of the TFT Tracker.";
inputs = {
nixpkgs.url = "github:NixOS/nixpkgs";
};
outputs = { self, nixpkgs, ... }:
let
supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin" ];
forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
nixpkgsFor = forAllSystems (system: import nixpkgs { inherit system; });
in
{
devShells = forAllSystems (system:
let
pkgs = nixpkgsFor.${system};
in {
default = pkgs.mkShell {
buildInputs = [
pkgs.elixir
];
shellHook = ''
mix local.hex --force
mix local.rebar --force
mix deps.get
'';
};
}
);
packages = forAllSystems (system:
let
pkgs = import nixpkgs { inherit system; };
in {
default = pkgs.stdenv.mkDerivation {
pname = "tft-tracker-bot";
version = "1.0.0";
src = self;
nativeBuildInputs = [ pkgs.cacert ];
buildInputs = [
pkgs.erlang
pkgs.elixir
];
SSL_CERT_FILE = "${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt";
buildPhase = ''
export SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt
mix local.hex --force
mix local.rebar --force
mix deps.get
mix compile
'';
ELIXIR_ERL_OPTIONS = "+fnu";
installPhase = ''
mkdir -p $out/bin
cp -r . $out/bin/
'';
meta = with pkgs.lib; {
description = "TFT Tracker discord bot";
license = licenses.mit;
maintainers = [ maintainers.sailorsnow ];
};
};
}
);
nixosModules.tftTrackerBot = {
options.services.tft-tracker-bot = {
enable = nixpkgs.lib.mkOption {
type = nixpkgs.lib.types.bool;
default = false;
description = "Enable the TFT Tracker discord bot service";
};
redisHost = nixpkgs.lib.mkOption {
type = nixpkgs.lib.types.string;
default = "127.0.0.1";
description = "Address of the redis host server.";
};
redisPort = nixpkgs.lib.mkOption {
type = nixpkgs.lib.types.int;
default = 6379;
description = "Port on which the redis server run.";
};
riotApiKey = nixpkgs.lib.mkOption {
type = nixpkgs.lib.types.string;
default = "";
description = "RIOT API Key to request game data.";
};
discordToken = nixpkgs.lib.mkOption {
type = nixpkgs.lib.types.string;
default = "";
description = "Discord Bot Token to control your bot account.";
};
};
config = { config, pkgs, lib, ... }: {
services.redis.enable = true;
environment.systemPackages = [ self.packages.${pkgs.system} ];
systemd.services.tft-tracker-bot = {
description = "TFT Tracker discord bot";
after = [ "network.target" ];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
WorkingDirectory = "${self.packages.${pkgs.system}}/bin";
ExecStart = "${self.packages.${pkgs.system}}/bin/_build/prod/rel/tft_tracker/ebin/tft_tracker start";
Restart = "always";
User = "username";
Environment = "MIX_ENV=dev";
};
};
networking.firewall.allowedTCPPorts = [ config.services.tft-tracker-bot.port ];
};
};
};
}
The shell environment is working as expected, but trying to build the derivation always result to the following elixir error:
error: builder for '/nix/store/367vl56wb700dgf0kp6z8kaig7yfx2zv-tft-tracker-bot-1.0.0.drv' failed with exit code 1;
last 10 log lines:
> 09:53:19.371 [error] Task #PID<0.109.0> started from #PID<0.94.0> terminating
> ** (MatchError) no match of right hand side value: {:error, :enoent}
> (public_key 1.13.3.4) pubkey_os_cacerts.erl:38: :pubkey_os_cacerts.get/0
> (mix 1.17.3) lib/mix/utils.ex:664: Mix.Utils.read_httpc/1
> (mix 1.17.3) lib/mix/utils.ex:576: anonymous fn/2 in Mix.Utils.read_path/2
> (elixir 1.17.3) lib/task/supervised.ex:101: Task.Supervised.invoke_mfa/2
> (elixir 1.17.3) lib/task/supervised.ex:36: Task.Supervised.reply/4
> Function: #Function<5.19587555/0 in Mix.Utils.read_path/2>
> Args: []
>
For full logs, run 'nix log /nix/store/367vl56wb700dgf0kp6z8kaig7yfx2zv-tft-tracker-bot-1.0.0.drv'.
This seems highly related to cacert, but I’ve kinda tried everything like export SSL env var required, importing cacert packages into my derivation, in buildInputs and nativeBuildInputs…
There isn’t much documentation on working with Elixir and Nix, but a lot of examples seems to be using mix2nix for getting the dependencies instead of the mix deps.get command, is this a no choice for working with an Elixir project right now ? It seems to be a bit overkill as I just want something that work for the moment, but I don’t know…
Thanks for any help !