4store database service: packaged

svn path=/nixos/trunk/; revision=26852

modules/misc/ids.nix

@@ -60,6 +60,7 @@ in
     kdm = 39;
     ghostOne = 40;
     git = 41;
+    fourStore = 42;
     # When adding a uid, make sure it doesn't match an existing gid.
 
     nixbld = 30000; # start of range of uids
@@ -102,6 +103,7 @@ in
     osgi = 34;
     ghostOne = 40;
     git = 41;
+    fourStore = 42;
     # When adding a gid, make sure it doesn't match an existing uid.
 
     users = 100;

modules/module-list.nix

@@ -51,6 +51,7 @@
   ./services/backup/mysql-backup.nix
   ./services/backup/postgresql-backup.nix
   ./services/backup/sitecopy-backup.nix
+  ./services/databases/4store.nix
   ./services/databases/mysql.nix
   ./services/databases/postgresql.nix
   ./services/databases/openldap.nix

modules/services/databases/4store.nix

@@ -0,0 +1,71 @@
+{ config, pkgs, ... }:
+let
+  cfg = config.services.fourStore;
+  stateDir = "/var/lib/4store";
+  fourStoreUser = "fourstore";
+  run = "${pkgs.su}/bin/su -s ${pkgs.stdenv.shell} ${fourStoreUser}";
+in
+with pkgs.lib;
+{
+
+  ###### interface
+
+  options = {
+  
+    services.fourStore = {
+    
+      enable = mkOption {
+        default = false;
+        description = "Whether to enable 4Store RDF database server.";
+      };
+
+      database = mkOption {
+        default = "";
+        description = "RDF database name. If it doesn't exist, it will be created. Databases are stored in ${stateDir}.";
+      };
+
+      options = mkOption {
+        default = "";
+        description = "Extra CLI options to pass to 4Store.";
+      };
+
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf cfg.enable (
+    mkAssert (cfg.enable -> cfg.database != "")
+      "Must specify database name" {
+
+    users.extraUsers = singleton
+      { name = fourStoreUser;
+        uid = config.ids.uids.fourStore;
+        description = "4Store database user";
+        home = stateDir;
+      };
+
+    services.avahi.enable = true;
+
+    jobs.fourStore = {
+      name = "4store";
+      startOn = "filesystem";
+
+      preStart = ''
+        mkdir -p ${stateDir}/
+        chown ${fourStoreUser} ${stateDir}
+	if ! test -e "${stateDir}/${cfg.database}"; then
+	  ${run} -c '${pkgs.rdf4store}/bin/4s-backend-setup ${cfg.database}'
+        fi
+      '';
+
+      exec = ''
+	${run} -c '${pkgs.rdf4store}/bin/4s-backend -D ${cfg.options} ${cfg.database}'
+      '';
+    };
+
+  });
+  
+}