nixos/eternal-terminal: init new module.

nixos/modules/module-list.nix

@@ -504,6 +504,7 @@
   ./services/networking/dnsmasq.nix
   ./services/networking/ejabberd.nix
   ./services/networking/epmd.nix
+  ./services/networking/eternal-terminal.nix
   ./services/networking/fakeroute.nix
   ./services/networking/ferm.nix
   ./services/networking/firefox/sync-server.nix

nixos/modules/services/networking/eternal-terminal.nix

@@ -0,0 +1,96 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.eternal-terminal;
+
+in
+
+{
+
+  ###### interface
+
+  options = {
+
+    services.eternal-terminal = {
+
+      enable = mkOption {
+        default = false;
+        type = types.bool;
+        description = ''
+          Enable the Eternal Terminal server.
+        '';
+      };
+
+      port = mkOption {
+        default = null;
+        type = types.nullOr types.int;
+        description = ''
+          The port the server should listen on. Will use the server's default (2022) if not specified.
+        '';
+      };
+
+      verbosity = mkOption {
+        default = 0;
+        type = types.int;
+        description = ''
+          The verbosity level (0-9).
+        '';
+      };
+
+      silence = mkOption {
+        default = 0;
+        type = types.int;
+        description = ''
+          Silence.
+        '';
+      };
+
+      logSize = mkOption {
+        default = 20971520;
+        type = types.int;
+        description = ''
+          The maximum log size.
+        '';
+      };
+    };
+  };
+
+  ###### implementation
+
+  config = mkIf cfg.enable {
+
+    # We need to ensure the et package is fully installed because
+    # the (remote) et client runs the `etterminal` binary when it
+    # connects.
+    environment.systemPackages = [ pkgs.eternal-terminal ];
+
+    systemd.services = {
+      eternal-terminal = {
+        description = "Eternal Terminal server.";
+        wantedBy = [ "multi-user.target" ];
+        after = [ "syslog.target" "network.target" ];
+        serviceConfig = {
+          Type = "forking";
+          ExecStart = "${pkgs.eternal-terminal}/bin/etserver --daemon --cfgfile=${pkgs.writeText "et.cfg" ''
+            ; et.cfg : Config file for Eternal Terminal
+            ;
+
+            ${optionalString (cfg.port != null) ''
+              [Networking]
+              port = ${toString cfg.port}
+            ''}
+            [Debug]
+            verbose = ${toString cfg.verbosity}
+            silent = ${toString cfg.silence}
+            logsize = ${toString cfg.logSize}
+          ''}";
+          Restart = "on-failure";
+          KillMode = "process";
+        };
+      };
+    };
+  };
+}