blog-pim/flake.nix

{
  description = "A very basic flake";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
    flutils.url = "github:numtide/flake-utils";

    nginx = {
      url = "github:nginx/nginx";
      flake = false;
    };
  };

  outputs = { self, nixpkgs, flutils, nginx }: flutils.lib.eachDefaultSystem (system:
    let
      pkgs = nixpkgs.legacyPackages.${system};

      gems = pkgs.bundlerEnv {
        name = "blog-pim";
        gemdir = ./src;
      };

      patch-feed-date = pkgs.stdenv.mkDerivation {
        name = "path-feed-date";
        propagatedBuildInputs = [ pkgs.python3 ];
        dontUnpack = true;
        installPhase = "install -Dm755 ${./patch-feed-date.py} $out/bin/patch-feed-date";
      };

      nginxPort = "80";
      nginxConf = pkgs.writeText "nginx.conf" ''
        user nobody nobody;
        daemon off;
        error_log /dev/stdout info;
        pid /dev/null;
        events {}
        http {
          access_log /dev/stdout;
          include ${nginx.outPath}/conf/mime.types;

          server {
            listen ${nginxPort};
            index index.html;
            location / {
              root ${self.packages.${system}.static-website};
            }
          }
        }
      '';
    in
    {
      packages = {
        static-website = pkgs.stdenv.mkDerivation {
          name = "blog-pim";
          src = ./src;
          sourceRoot = "src";

          buildInputs = [
            gems
            gems.wrappedRuby
            patch-feed-date
          ];

          buildPhase = ''
            bundle exec jekyll build
          '';

          installPhase = ''
            mkdir -p $out
            cp -r _site/* $out/
            patch-feed-date --file _site/feed.xml > $out/feed.xml
          '';
        };

        container-image = pkgs.dockerTools.buildLayeredImage {
          name = "blog-pim";
          tag = "latest";

          contents = [
            pkgs.fakeNss
            pkgs.nginx
          ];

          extraCommands = ''
            mkdir -p tmp/nginx_client_body
            mkdir -p var/log/nginx
          '';

          config = {
            Cmd = [ "nginx" "-c" nginxConf ];
            ExposedPorts = {
              "${nginxPort}/tcp" = { };
            };
          };
        };
      };
    });
}