1 files changed, 105 insertions, 41 deletions

diff --git a/nixpkgs/nixos/modules/services/logging/logrotate.nix b/nixpkgs/nixos/modules/services/logging/logrotate.nix
index 565618b27a8..7d6102b8255 100644
--- a/nixpkgs/nixos/modules/services/logging/logrotate.nix
+++ b/nixpkgs/nixos/modules/services/logging/logrotate.nix
@@ -5,54 +5,93 @@ with lib;
 let
   cfg = config.services.logrotate;
 
-  pathOptions = {
+  pathOpts = {
     options = {
+      enable = mkOption {
+        type = types.bool;
+        default = true;
+        description = ''
+          Whether to enable log rotation for this path. This can be used to explicitly disable
+          logging that has been configured by NixOS.
+        '';
+      };
+
       path = mkOption {
         type = types.str;
-        description = "The path to log files to be rotated";
+        description = ''
+          The path to log files to be rotated.
+        '';
       };
+
       user = mkOption {
-        type = types.str;
-        description = "The user account to use for rotation";
+        type = with types; nullOr str;
+        default = null;
+        description = ''
+          The user account to use for rotation.
+        '';
       };
+
       group = mkOption {
-        type = types.str;
-        description = "The group to use for rotation";
+        type = with types; nullOr str;
+        default = null;
+        description = ''
+          The group to use for rotation.
+        '';
       };
+
       frequency = mkOption {
-        type = types.enum [
-          "daily" "weekly" "monthly" "yearly"
-        ];
+        type = types.enum [ "daily" "weekly" "monthly" "yearly" ];
         default = "daily";
-        description = "How often to rotate the logs";
+        description = ''
+          How often to rotate the logs.
+        '';
       };
+
       keep = mkOption {
         type = types.int;
         default = 20;
-        description = "How many rotations to keep";
+        description = ''
+          How many rotations to keep.
+        '';
       };
+
       extraConfig = mkOption {
         type = types.lines;
         default = "";
-        description = "Extra logrotate config options for this path";
+        description = ''
+          Extra logrotate config options for this path. Refer to
+          <link xlink:href="https://linux.die.net/man/8/logrotate"/> for details.
+        '';
+      };
+
+      priority = mkOption {
+        type = types.int;
+        default = 1000;
+        description = ''
+          Order of this logrotate block in relation to the others. The semantics are
+          the same as with `lib.mkOrder`. Smaller values have a greater priority.
+        '';
       };
     };
-  };
 
-  pathConfig = options: ''
-    "${options.path}" {
-      su ${options.user} ${options.group}
-      ${options.frequency}
+    config.extraConfig = ''
       missingok
       notifempty
-      rotate ${toString options.keep}
-      ${options.extraConfig}
+    '';
+  };
+
+  mkConf = pathOpts: ''
+    # generated by NixOS using the `services.logrotate.paths.${pathOpts.name}` attribute set
+    "${pathOpts.path}" {
+      ${optionalString (pathOpts.user != null || pathOpts.group != null) "su ${pathOpts.user} ${pathOpts.group}"}
+      ${pathOpts.frequency}
+      rotate ${toString pathOpts.keep}
+      ${pathOpts.extraConfig}
     }
   '';
 
-  configFile = pkgs.writeText "logrotate.conf" (
-    (concatStringsSep "\n" ((map pathConfig cfg.paths) ++ [cfg.extraConfig]))
-  );
+  paths = sortProperties (mapAttrsToList (name: pathOpts: pathOpts // { name = name; }) (filterAttrs (_: pathOpts: pathOpts.enable) cfg.paths));
+  configFile = pkgs.writeText "logrotate.conf" (concatStringsSep "\n" ((map mkConf paths) ++ [ cfg.extraConfig ]));
 
 in
 {
@@ -65,41 +104,66 @@ in
       enable = mkEnableOption "the logrotate systemd service";
 
       paths = mkOption {
-        type = types.listOf (types.submodule pathOptions);
-        default = [];
-        description = "List of attribute sets with paths to rotate";
-        example = {
-          "/var/log/myapp/*.log" = {
-            user = "myuser";
-            group = "mygroup";
-            rotate = "weekly";
-            keep = 5;
-          };
-        };
+        type = with types; attrsOf (submodule pathOpts);
+        default = {};
+        description = ''
+          Attribute set of paths to rotate. The order each block appears in the generated configuration file
+          can be controlled by the <link linkend="opt-services.logrotate.paths._name_.priority">priority</link> option
+          using the same semantics as `lib.mkOrder`. Smaller values have a greater priority.
+        '';
+        example = literalExample ''
+          {
+            httpd = {
+              path = "/var/log/httpd/*.log";
+              user = config.services.httpd.user;
+              group = config.services.httpd.group;
+              keep = 7;
+            };
+
+            myapp = {
+              path = "/var/log/myapp/*.log";
+              user = "myuser";
+              group = "mygroup";
+              frequency = "weekly";
+              keep = 5;
+              priority = 1;
+            };
+          }
+        '';
       };
 
       extraConfig = mkOption {
         default = "";
         type = types.lines;
         description = ''
-          Extra contents to add to the logrotate config file.
-          See https://linux.die.net/man/8/logrotate
+          Extra contents to append to the logrotate configuration file. Refer to
+          <link xlink:href="https://linux.die.net/man/8/logrotate"/> for details.
         '';
       };
     };
   };
 
   config = mkIf cfg.enable {
-    systemd.services.logrotate = {
-      description   = "Logrotate Service";
-      wantedBy      = [ "multi-user.target" ];
-      startAt       = "*-*-* *:05:00";
+    assertions = mapAttrsToList (name: pathOpts:
+      { assertion = (pathOpts.user != null) == (pathOpts.group != null);
+        message = ''
+          If either of `services.logrotate.paths.${name}.user` or `services.logrotate.paths.${name}.group` are specified then *both* must be specified.
+        '';
+      }
+    ) cfg.paths;
 
-      serviceConfig.Restart = "no";
-      serviceConfig.User    = "root";
+    systemd.services.logrotate = {
+      description = "Logrotate Service";
+      wantedBy = [ "multi-user.target" ];
+      startAt = "*-*-* *:05:00";
       script = ''
         exec ${pkgs.logrotate}/sbin/logrotate ${configFile}
       '';
+
+      serviceConfig = {
+        Restart = "no";
+        User = "root";
+      };
     };
   };
 }