Add initial prototype of NixOS module

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>

flake.lock

@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1766736597,
+        "narHash": "sha256-BASnpCLodmgiVn0M1MU2Pqyoz0aHwar/0qLkp7CjvSQ=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "f560ccec6b1116b22e6ed15f4c510997d99d5852",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-25.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,29 @@
+{
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.11";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+        let
+	  pkgs = import nixpkgs { inherit system; };
+	  joann-pupper-bot = pkgs.crystal.buildCrystalPackage {
+	    pname = "joann-pupper-bot";
+	    version = "0.1.0";
+	    src = ./.;
+            lockFile = ./shard.lock;
+	    shardsFile = ./shards.nix;
+	    format = "shards";
+	    buildInputs = [pkgs.sqlite];
+	  };
+        in
+          {
+            packages = { inherit joann-pupper-bot; };
+            defaultPackage = joann-pupper-bot;
+          }
+    ) // {
+      nixosModules.joann-pupper-bot = import ./module.nix;
+    };
+}

module.nix

@@ -0,0 +1,71 @@
+{ config, lib, pkgs, ... }:
+with lib;
+let cfg = config.services.joann-pupper-bot; in {
+  options.services.joann-pupper-bot = {
+    enable = mkEnableOption "Joann's Pupper Bot";
+    user = mkOption {
+      type = types.str;
+      default = "joann-pupper-bot";
+      example = "myuser";
+      description = "Which user should be running Joann's Pupper Bot";
+    };
+    group = mkOption {
+      type = types.str;
+      default = "joann-pupper-bot";
+      example = "mygroup";
+      description = "Which group should be running Joann's Pupper Bot";
+    };
+    stateDir = mkOption {
+      type = types.str;
+      default = "/var/lib/joann-pupper-bot";
+      description = "Which directory the bot should use for storage";
+    };
+    config.token = mkOption {
+      type = types.str;
+      description = "Bot token used for Telegram";
+    };
+    config.subreddits = mkOption {
+      type = types.listOf types.str;
+      description = "Which subreddits to draw images from";
+      default = ["rarepuppers"];
+    };
+    config.sendCron = mkOption {
+      type = types.str;
+      description = "cron-style string determining when images should be sent";
+      default = "*/30 8-21 * * *";
+    };
+    config.refreshCron = mkOption {
+      type = types.str;
+      description = "cron-style string determining when the bot polls Reddit for new images";
+      default = "*/15 * * * *";
+    };
+    config.recipients = mkOption {
+      type = types.listOf types.int;
+      description = "Telegram chat IDs for each of the image recipients";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.tmpfiles.rules = [
+      "d '${cfg.stateDir}' 0750 ${cfg.user} ${cfg.group} - -"
+    ];
+    systemd.services.joann-pupper-bot = {
+      description = "Joann's Pupper Bot";
+      wantedBy = [ "multi-user.target" ];
+
+      preStart =
+        let
+          yml = generators.toYAML {} cfg.config;
+          configFile = pkgs.writeText "config.yaml" yml;
+        in
+        ''
+          cp -f '${configFile}' '${cfg.stateDir}'/config.yaml
+        '';
+
+      serviceConfig = {
+	Type = "oneshot";
+        ExecStart = "/bin/sh -c :";
+      };
+    };
+  };
+}

shard.lock

@@ -0,0 +1,22 @@
+version: 2.0
+shards:
+  cron_parser:
+    git: https://github.com/kostya/cron_parser.git
+    version: 0.4.0
+
+  cron_scheduler:
+    git: https://github.com/kostya/cron_scheduler.git
+    version: 0.4.0
+
+  db:
+    git: https://github.com/crystal-lang/crystal-db.git
+    version: 0.14.0
+
+  sqlite3:
+    git: https://github.com/crystal-lang/crystal-sqlite3.git
+    version: 0.22.0
+
+  telepathy:
+    git: https://dev.danilafe.com/Crystal-Bots/telepathy
+    version: 0.2.0
+

shard.yml

@@ -16,6 +16,6 @@ dependencies:
   sqlite3:
     github: crystal-lang/crystal-sqlite3
 
-crystal: 0.24.1
+crystal: 1.0.0
 
 license: MIT

shards.nix

@@ -0,0 +1,27 @@
+{
+  "cron_parser" = {
+    url = "https://github.com/kostya/cron_parser.git";
+    rev = "v0.4.0";
+    sha256 = "17fgg2nvyx99v05l10h6cnxfr7swz8yaxhmnk4l47kg2spi8w90a";
+  };
+  "cron_scheduler" = {
+    url = "https://github.com/kostya/cron_scheduler.git";
+    rev = "v0.4.0";
+    sha256 = "0jd0maw1h87hjgjpqhbwxb4yz83g8shlrwfivyf0sd6x3l5lspns";
+  };
+  "db" = {
+    url = "https://github.com/crystal-lang/crystal-db.git";
+    rev = "v0.14.0";
+    sha256 = "1s67fs5abzgg2yyjsm2la967mk881i91h8jdnal072fb9qh9wr58";
+  };
+  "sqlite3" = {
+    url = "https://github.com/crystal-lang/crystal-sqlite3.git";
+    rev = "v0.22.0";
+    sha256 = "1lc8ixnzjx8nsp96qj9yxmfk7g334id8v87g3h5bwgkhkbx5ghqn";
+  };
+  "telepathy" = {
+    url = "https://dev.danilafe.com/Crystal-Bots/telepathy";
+    rev = "v0.2.0";
+    sha256 = "1zhjlpa31vldgd9f6l1hdfj7a97hlqkxkvxzisfs2zfnvc86aiyc";
+  };
+}

src/joann-pupper-bot/bot.cr

@@ -1,18 +1,18 @@
-require "logger"
+require "log"
 require "telepathy"
 require "time"
 require "sqlite3"
 require "cron_scheduler"
 
 EXTENSIONS = ["png", "jpeg", "jpg"]
-LOGGER = Logger.new(STDOUT)
+LOGGER = Log.for("joann-pupper-bot")
 
 class PupperBot
    @db : DB::Database
 
   def initialize(@configuration : BotConfiguration)
-    @telegram_bot = Telepathy::Bot.new configuration.token
-    @db = DB.open "sqlite3://#{configuration.database}"
+    @telegram_bot = Telepathy::Bot.new @configuration.token
+    @db = DB.open "sqlite3://#{@configuration.database}"
     initialize_db
     update_database
     initialize_timers
@@ -49,12 +49,12 @@ class PupperBot
     unsent_query = "select id, title, url from posts where not exists (select * from recepient_posts where recepient=? and post=id) limit 1"
 
     unless to_send = @db.query_one? unsent_query, chatid, as: { Int64, String, String }
-      LOGGER.info "Unable to find a post to send to #{chatid}."
+      LOGGER.info { "Unable to find a post to send to #{chatid}." }
       return
     end
 
     id, title, url = to_send
-    LOGGER.info "Using URL #{url} for request from #{chatid}"
+    LOGGER.info { "Using URL #{url} for request from #{chatid}" }
     @db.exec "insert into recepient_posts(recepient, post) values(?, ?)", chatid, id
     @telegram_bot.send_photo(chatid, url, title)
   end
@@ -67,13 +67,13 @@ class PupperBot
 
   def update_database
     unless response = RedditResponse.from_subreddits(@configuration.subreddits)
-      LOGGER.info "Unable to find more posts for the database"
+      LOGGER.info { "Unable to find more posts for the database" }
       return
     end
 
     posts = response.data.posts_matching { |post| EXTENSIONS.any? { |it| post.url.ends_with? it } }
     posts.each do |post|
-      LOGGER.info "Trying to save post #{post.title} #{post.url}"
+      LOGGER.info { "Trying to save post #{post.title} #{post.url}" }
       begin
         @db.exec "insert into posts(title, url) values(?, ?)", post.title, post.url
       rescue

src/joann-pupper-bot/config.cr

@@ -1,11 +1,23 @@
 require "yaml"
 
 class BotConfiguration
-  YAML.mapping(
-    token: String,
-    database: { type: String, default: "./data.sqlite" },
-    subreddits: { type: Array(String), default: [ "rarepuppers" ] },
-    send_cron: { type: String, default: "*/30 8-21 * * *" },
-    refresh_cron: { type: String, default: "*/15 * * * *" },
-    recipients: Array(Int64))
+  include YAML::Serializable
+
+  @[YAML::Field(key: "token")]
+  property token : String
+
+  @[YAML::Field(key: "database")]
+  property database : String = "./data.sqlite"
+
+  @[YAML::Field(key: "subreddits")]
+  property subreddits : Array(String) = ["rarepuppers"]
+
+  @[YAML::Field(key: "send_cron")]
+  property send_cron : String = "*/30 8-21 * * *"
+
+  @[YAML::Field(key: "refresh_cron")]
+  property refresh_cron : String = "*/15 * * * *"
+
+  @[YAML::Field(key: "recipients")]
+  property recipients : Array(Int64)
 end

src/joann-pupper-bot/reddit.cr

@@ -2,23 +2,39 @@ require "http/client"
 require "json"
 
 class RedditWrapper(T)
-  JSON.mapping(
-    kind: String,
-    data: T)
+  include JSON::Serializable
+
+  @[JSON::Field(key: "kind")]
+  property kind : String
+
+  @[JSON::Field(key: "data")]
+  property data : T
 end
 
 class RedditChild
-  JSON.mapping(
-    url: String,
-    name: String,
-    title: String)
+  include JSON::Serializable
+
+  @[JSON::Field(key: "url")]
+  property url : String
+
+  @[JSON::Field(key: "name")]
+  property name : String
+
+  @[JSON::Field(key: "title")]
+  property title : String
 end
 
 class RedditResponse
-  JSON.mapping(
-    modhash: String,
-    dist: Int32,
-    children: Array(RedditWrapper(RedditChild)))
+  include JSON::Serializable
+
+  @[JSON::Field(key: "modhash")]
+  property modhash : String
+
+  @[JSON::Field(key: "dist")]
+  property dist : Int32
+
+  @[JSON::Field(key: "children")]
+  property children : Array(RedditWrapper(RedditChild))
 
   def self.from_subreddits(subreddits : Array(String))
     request_url = URI.new scheme: "https", host: "www.reddit.com", path: "/r/#{subreddits.join "+"}/hot.json", query: "limit=30"