2 files changed, 138 insertions, 0 deletions
diff --git a/modules/apps/memcached/default.nix b/modules/apps/memcached/default.nix
new file mode 100644
index 0000000..e963518
--- /dev/null
+++ b/modules/apps/memcached/default.nix
@@ -0,0 +1,67 @@
+{ config, lib, pkgs, ... }:
+
+let
+
+  inherit (builtins)
+    elem filter isBool isList ;
+
+  inherit (lib)
+    concatMapStringsSep concatStringsSep filterAttrs flatten foldAttrs foldl
+    mapAttrsToList mkOption optionalString ;
+
+  inherit (lib.types)
+    attrsOf submodule ;
+
+  concatMapAttrsSep = s: f: attrs: concatStringsSep s (mapAttrsToList f attrs);
+
+  explicit = filterAttrs (n: v: n != "_module" && v != null);
+  instances = explicit config.nixsap.apps.memcached;
+  users = mapAttrsToList (_: i: i.user) instances;
+
+
+  mkService = name: cfg:
+    let
+
+      show = n: v:
+        if isList v then map (s: "-${n} '${toString s}'") v
+        else if isBool v then (optionalString v "-${n}")
+        else "-${n} '${toString v}'";
+
+      args = flatten (mapAttrsToList show (explicit cfg.args));
+
+      start = pkgs.writeBashScriptBin "memcached-${name}-start" ''
+        set -euo pipefail
+        umask 0027
+
+        exec ${cfg.package}/bin/memcached \
+        ${concatStringsSep " \\\n" args}
+      '';
+
+    in {
+      "memcached-${name}" = {
+        description = "memcached (${name})";
+        wantedBy = [ "multi-user.target" ];
+        after = [ "keys.target" "network.target" "local-fs.target" ];
+        serviceConfig = {
+          ExecStart = "${start}/bin/memcached-${name}-start";
+          Restart = "always";
+          User = cfg.user;
+        };
+      };
+    };
+
+in {
+
+  options.nixsap.apps.memcached = mkOption {
+    description = "Memcached instances";
+    default = {};
+    type = attrsOf (submodule (import ./instance.nix pkgs));
+  };
+
+  config = {
+    systemd.services = foldl (a: b: a//b) {} (mapAttrsToList mkService instances);
+    nixsap.system.users.daemons = users;
+  };
+
+}
+
diff --git a/modules/apps/memcached/instance.nix b/modules/apps/memcached/instance.nix
new file mode 100644
index 0000000..102a287
--- /dev/null
+++ b/modules/apps/memcached/instance.nix
@@ -0,0 +1,71 @@
+pkgs:
+{ lib, name, ... }:
+
+let
+
+  inherit (builtins) match ;
+
+  inherit (lib)
+    mkOption mkOptionType ;
+
+  inherit (lib.types)
+    bool either enum int listOf nullOr package path str submodule ;
+
+  default = v: type: mkOption { type = type; default = v; };
+  optional = type: mkOption { type = nullOr type; default = null; };
+
+  isFloat = x: match "^[0-9]+(\\.[0-9]+)?$" (toString x) != null;
+
+  float = mkOptionType {
+    name = "positive float";
+    check = isFloat;
+  };
+
+in {
+  options = {
+
+    user = mkOption {
+      description = "User to run as";
+      type = str;
+      default = "memcached-${name}";
+    };
+
+    package = mkOption {
+      description = "Memcached package";
+      type = package;
+      default = pkgs.memcached;
+    };
+
+    args = mkOption {
+      description = "Memcached command line arguments. Refer to memcached man page.";
+      default = {};
+      type = submodule {
+        options = {
+          M = optional bool;
+          R = optional int;
+          B = optional (enum ["auto" "ascii" "binary"]);
+          I = optional int;
+          L = optional bool;
+          l = default "127.0.0.1" (either str (listOf str));
+          b = optional int;
+          c = optional int;
+          f = optional float;
+          p = default 11211 int;
+          t = optional int;
+          D = optional str;
+          a = optional str;
+          m = optional int;
+          n = optional int;
+          F = optional bool;
+          U = default 11211 int;
+          C = optional bool;
+          k = optional bool;
+          A = optional bool;
+          S = optional bool;
+          s = optional path;
+        };
+      };
+    };
+  };
+}
+