nixos/bcg: init module

This is gateway that transforms BigClown wireless to MQTT.

nixos/modules/module-list.nix

@@ -608,6 +608,7 @@
   ./services/misc/autorandr.nix
   ./services/misc/autosuspend.nix
   ./services/misc/bazarr.nix
+  ./services/misc/bcg.nix
   ./services/misc/beanstalkd.nix
   ./services/misc/bees.nix
   ./services/misc/bepasty.nix

nixos/modules/services/misc/bcg.nix

@@ -0,0 +1,175 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+with lib;
+
+let
+  cfg = config.services.bcg;
+  configFile = (pkgs.formats.yaml {}).generate "bcg.conf.yaml" (
+    filterAttrsRecursive (n: v: v != null) {
+      inherit (cfg) device name mqtt;
+      retain_node_messages = cfg.retainNodeMessages;
+      qos_node_messages = cfg.qosNodeMessages;
+      base_topic_prefix = cfg.baseTopicPrefix;
+      automatic_remove_kit_from_names = cfg.automaticRemoveKitFromNames;
+      automatic_rename_kit_nodes = cfg.automaticRenameKitNodes;
+      automatic_rename_generic_nodes = cfg.automaticRenameGenericNodes;
+      automatic_rename_nodes = cfg.automaticRenameNodes;
+    }
+  );
+in
+{
+  options = {
+    services.bcg = {
+      enable = mkEnableOption (mdDoc "BigClown gateway");
+      package = mkOption {
+        default = pkgs.python3Packages.bcg;
+        defaultText = literalExpression "pkgs.python3Packages.bcg";
+        description = mdDoc "Which bcg derivation to use.";
+        type = types.package;
+      };
+      environmentFiles = mkOption {
+        type = types.listOf types.path;
+        default = [];
+        example = [ "/run/keys/bcg.env" ];
+        description = mdDoc ''
+          File to load as environment file. Environment variables from this file
+          will be interpolated into the config file using envsubst with this
+          syntax: `$ENVIRONMENT` or `''${VARIABLE}`.
+          This is useful to avoid putting secrets into the nix store.
+        '';
+      };
+      verbose = mkOption {
+        type = types.enum ["CRITICAL" "ERROR" "WARNING" "INFO" "DEBUG"];
+        default = "WARNING";
+        description = mdDoc "Verbosity level.";
+      };
+      device = mkOption {
+        type = types.str;
+        description = mdDoc "Device name to configure gateway to use.";
+      };
+      name = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        description = mdDoc ''
+          Name for the device.
+
+          Supported variables:
+          * `{ip}` IP address
+          * `{id}` The ID of the connected usb-dongle or core-module
+
+          `null` can be used for automatic detection from gateway firmware.
+        '';
+      };
+      mqtt = {
+        host = mkOption {
+          type = types.str;
+          default = "127.0.0.1";
+          description = mdDoc "Host where MQTT server is running.";
+        };
+        port = mkOption {
+          type = types.port;
+          default = 1883;
+          description = mdDoc "Port of MQTT server.";
+        };
+        username = mkOption {
+          type = with types; nullOr str;
+          default = null;
+          description = mdDoc "MQTT server access username.";
+        };
+        password = mkOption {
+          type = with types; nullOr str;
+          default = null;
+          description = mdDoc "MQTT server access password.";
+        };
+        cafile = mkOption {
+          type = with types; nullOr str;
+          default = null;
+          description = mdDoc "Certificate Authority file for MQTT server access.";
+        };
+        certfile = mkOption {
+          type = with types; nullOr str;
+          default = null;
+          description = mdDoc "Certificate file for MQTT server access.";
+        };
+        keyfile = mkOption {
+          type = with types; nullOr str;
+          default = null;
+          description = mdDoc "Key file for MQTT server access.";
+        };
+      };
+      retainNodeMessages = mkOption {
+        type = types.bool;
+        default = false;
+        description = mdDoc "Specify that node messages should be retaied in MQTT broker.";
+      };
+      qosNodeMessages = mkOption {
+        type = types.int;
+        default = 1;
+        description = mdDoc "Set the guarantee of MQTT message delivery.";
+      };
+      baseTopicPrefix = mkOption {
+        type = types.str;
+        default = "";
+        description = mdDoc "Topic prefix added to all MQTT messages.";
+      };
+      automaticRemoveKitFromNames = mkOption {
+        type = types.bool;
+        default = true;
+        description = mdDoc "Automatically remove kits.";
+      };
+      automaticRenameKitNodes = mkOption {
+        type = types.bool;
+        default = true;
+        description = mdDoc "Automatically rename kit's nodes.";
+      };
+      automaticRenameGenericNodes = mkOption {
+        type = types.bool;
+        default = true;
+        description = mdDoc "Automatically rename generic nodes.";
+      };
+      automaticRenameNodes = mkOption {
+        type = types.bool;
+        default = true;
+        description = mdDoc "Automatically rename all nodes.";
+      };
+      rename = mkOption {
+        type = with types; attrsOf str;
+        default = {};
+        description = mdDoc "Rename nodes to different name.";
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = with pkgs; [
+      python3Packages.bcg
+      python3Packages.bch
+    ];
+
+    systemd.services.bcg = let
+      envConfig = cfg.environmentFiles != [];
+      finalConfig = if envConfig
+                    then "$RUNTIME_DIRECTORY/bcg.config.yaml"
+                    else configFile;
+    in {
+      description = "BigClown Gateway";
+      wantedBy = [ "multi-user.target" ];
+      wants = mkIf config.services.mosquitto.enable [ "mosquitto.service" ];
+      after = [ "network-online.target" ];
+      preStart = ''
+        umask 077
+        ${pkgs.envsubst}/bin/envsubst -i "${configFile}" -o "${finalConfig}"
+        '';
+      serviceConfig = {
+        EnvironmentFile = cfg.environmentFiles;
+        ExecStart="${cfg.package}/bin/bcg -c ${finalConfig} -v ${cfg.verbose}";
+        RuntimeDirectory = "bcg";
+      };
+    };
+  };
+}