2 files changed, 113 insertions, 0 deletions
diff --git a/krebs/3modules/default.nix b/krebs/3modules/default.nix
index f3180722d..2772bf986 100644
--- a/krebs/3modules/default.nix
+++ b/krebs/3modules/default.nix
@@ -27,6 +27,7 @@ let
       ./github-known-hosts.nix
       ./git.nix
       ./go.nix
+      ./gollum.nix
       ./hidden-ssh.nix
       ./hosts.nix
       ./htgen.nix
diff --git a/krebs/3modules/gollum.nix b/krebs/3modules/gollum.nix
new file mode 100644
index 000000000..4b4e04d16
--- /dev/null
+++ b/krebs/3modules/gollum.nix
@@ -0,0 +1,112 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.krebs.gollum;
+in
+
+{
+  options.krebs.gollum = {
+    enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Enable the Gollum service.";
+    };
+
+    address = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      description = "IP address on which the web server will listen.";
+    };
+
+    port = mkOption {
+      type = types.int;
+      default = 4567;
+      description = "Port on which the web server will run.";
+    };
+
+    extraConfig = mkOption {
+      type = types.lines;
+      default = "";
+      description = "Content of the configuration file";
+    };
+
+    mathjax = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Enable support for math rendering using MathJax";
+    };
+
+    allowUploads = mkOption {
+      type = types.nullOr (types.enum [ "dir" "page" ]);
+      default = null;
+      description = "Enable uploads of external files";
+    };
+
+    emoji = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Parse and interpret emoji tags";
+    };
+
+    branch = mkOption {
+      type = types.str;
+      default = "master";
+      example = "develop";
+      description = "Git branch to serve";
+    };
+
+    stateDir = mkOption {
+      type = types.path;
+      default = "/var/lib/gollum";
+      description = "Specifies the path of the repository directory. If it does not exist, Gollum will create it on startup.";
+    };
+
+  };
+
+  config = mkIf cfg.enable {
+
+    users.users.gollum = {
+      group = config.users.users.gollum.name;
+      description = "Gollum user";
+      home = cfg.stateDir;
+      createHome = false;
+      isSystemUser = true;
+    };
+
+    users.groups.gollum = { };
+
+    systemd.tmpfiles.rules = [
+      "d '${cfg.stateDir}' - ${config.users.users.gollum.name} ${config.users.groups.gollum.name} - -"
+    ];
+
+    systemd.services.gollum = {
+      description = "Gollum wiki";
+      after = [ "network.target" ];
+      wantedBy = [ "multi-user.target" ];
+      path = [ pkgs.git ];
+
+      preStart = ''
+        # This is safe to be run on an existing repo
+        git init ${cfg.stateDir}
+      '';
+
+      serviceConfig = {
+        User = config.users.users.gollum.name;
+        Group = config.users.groups.gollum.name;
+        ExecStart = ''
+          ${pkgs.gollum}/bin/gollum \
+            --port ${toString cfg.port} \
+            --host ${cfg.address} \
+            --config ${pkgs.writeText "gollum-config.rb" cfg.extraConfig} \
+            --ref ${cfg.branch} \
+            ${optionalString cfg.mathjax "--mathjax"} \
+            ${optionalString cfg.emoji "--emoji"} \
+            ${optionalString (cfg.allowUploads != null) "--allow-uploads ${cfg.allowUploads}"} \
+            ${cfg.stateDir}
+        '';
+      };
+    };
+  };
+}