launchd: add user agents

modules/launchd/default.nix

@@ -35,7 +35,7 @@ let
         path = mkOption {
           type = types.listOf types.path;
           default = [];
-          apply = ps: "${makeBinPath ps}";
+          apply = ps: makeBinPath ps;
           description = ''
             Packages added to the service's <envar>PATH</envar>
             environment variable.  Both the <filename>bin</filename>
@@ -117,6 +117,22 @@ in
       '';
     };
 
+    launchd.user.agents = mkOption {
+      default = {};
+      type = types.attrsOf (types.submodule serviceOptions);
+      description = ''
+        Definition of per-user launchd agents.
+
+        When a user logs in, a per-user launchd is started.
+        It does the following:
+        1. It loads the parameters for each launch-on-demand user agent from the property list files found in /System/Library/LaunchAgents, /Library/LaunchAgents, and the user’s individual Library/LaunchAgents directory.
+        2. It registers the sockets and file descriptors requested by those user agents.
+        3. It launches any user agents that requested to be running all the time.
+        4. As requests for a particular service arrive, it launches the corresponding user agent and passes the request to it.
+        5. When the user logs out, it sends a SIGTERM signal to all of the user agents that it started.
+      '';
+    };
+
   };
 
   config = {
@@ -124,5 +140,7 @@ in
     environment.launchAgents = mapAttrs' toEnvironmentText cfg.agents;
     environment.launchDaemons = mapAttrs' toEnvironmentText cfg.daemons;
 
+    environment.userLaunchAgents = mapAttrs' toEnvironmentText cfg.user.agents;
+
   };
 }

modules/system/activation-scripts.nix

@@ -84,6 +84,7 @@ in
       umask 0022
 
       ${cfg.activationScripts.defaults.text}
+      ${cfg.activationScripts.userLaunchd.text}
       ${cfg.activationScripts.extraUserActivation.text}
 
       exit $_status

modules/system/default.nix

@@ -92,6 +92,7 @@ in
         ln -s ${cfg.path} $out/sw
 
         mkdir -p $out/Library
+        ln -s ${cfg.build.launchd}/Library/LaunchAgents $out/Library/LaunchAgents
         ln -s ${cfg.build.launchd}/Library/LaunchDaemons $out/Library/LaunchDaemons
 
         echo "$activationScript" > $out/activate

modules/system/launchd.nix

@@ -13,14 +13,23 @@ let
 
   launchdActivation = basedir: target: ''
     if test -f '/Library/${basedir}/${target}'; then
-      launchctl unload '/Library/${basedir}/${target}'
+      launchctl unload '/Library/${basedir}/${target}' || true
     fi
     cp -f '${cfg.build.launchd}/Library/${basedir}/${target}' '/Library/${basedir}/${target}'
     launchctl load '/Library/${basedir}/${target}'
   '';
 
+  userLaunchdActivation = target: ''
+    if test -f ~/Library/LaunchAgents/${target}; then
+      launchctl unload ~/Library/LaunchAgents/${target} || true
+    fi
+    cp -f ${cfg.build.userLaunchd}/Library/LaunchAgents/${target} ~/Library/LaunchAgents/${target}
+    launchctl load ~/Library/LaunchAgents/${target}
+  '';
+
   launchAgents = filter (f: f.enable) (attrValues config.environment.launchAgents);
   launchDaemons = filter (f: f.enable) (attrValues config.environment.launchDaemons);
+  userLaunchAgents = filter (f: f.enable) (attrValues config.environment.userLaunchAgents);
 
 in
 
@@ -43,6 +52,14 @@ in
       '';
     };
 
+    environment.userLaunchAgents = mkOption {
+      type = types.loaOf (types.submodule text);
+      default = {};
+      description = ''
+        Set of files that have to be linked in <filename>~/Library/LaunchAgents</filename>.
+      '';
+    };
+
   };
 
   config = {
@@ -55,6 +72,12 @@ in
       ${concatMapStringsSep "\n" (attr: "ln -s '${attr.source}' '${attr.target}'") launchDaemons}
     '';
 
+    system.build.userLaunchd = pkgs.runCommand "user-launchd" {} ''
+      mkdir -p $out/Library/LaunchAgents $out/Library/LaunchDaemons
+      cd $out/Library/LaunchAgents
+      ${concatMapStringsSep "\n" (attr: "ln -s '${attr.source}' '${attr.target}'") userLaunchAgents}
+    '';
+
     system.activationScripts.launchd.text = ''
       # Set up launchd services in /Library/LaunchAgents and /Library/LaunchDaemons
       echo "setting up launchd services..."
@@ -63,5 +86,12 @@ in
       ${concatMapStringsSep "\n" (attr: launchdActivation "LaunchDaemons" attr.target) launchDaemons}
     '';
 
+    system.activationScripts.userLaunchd.text = ''
+      # Set up launchd services in ~/Library/LaunchAgents
+      echo "setting up user launchd services..."
+
+      ${concatMapStringsSep "\n" (attr: userLaunchdActivation attr.target) userLaunchAgents}
+    '';
+
   };
 }