services.mysqlBackup: allow gzip to use compressionLevel too

NixOS · Dec 31, 2024 · d28fa69 · d28fa69
1 parent fba19a8
commit d28fa69
Showing 1 changed file with 9 additions and 7 deletions.
diff --git a/nixos/modules/services/backup/mysql-backup.nix b/nixos/modules/services/backup/mysql-backup.nix
@@ -27,16 +27,17 @@ let
   validCompressionLevels = {
     zstd = range: 1 <= range && range <= 19;
     xz = range: 0 <= range && range <= 9;
-    gzip = range: false; # gzip doesn't use compressionLevel
+    gzip = range: 1 <= range && range <= 9;
   };
 
   compressionCmd =
     let
-      compressionLevelFlag =
-        if cfg.compressionLevel != null then "-${toString cfg.compressionLevel}" else "";
+      compressionLevelFlag = lib.optionalString (cfg.compressionLevel != null) (
+        "-" + toString cfg.compressionLevel
+      );
     in
     {
-      gzip = "${pkgs.gzip}/bin/gzip -c ${cfg.gzipOptions}";
+      gzip = "${pkgs.gzip}/bin/gzip -c ${cfg.gzipOptions} ${compressionLevelFlag}";
       xz = "${pkgs.xz}/bin/xz -z -c ${compressionLevelFlag} -";
       zstd = "${pkgs.zstd}/bin/zstd ${compressionLevelFlag} -";
     }
@@ -95,10 +96,10 @@ in
         type = lib.types.nullOr lib.types.int;
         default = null;
         description = ''
-          Compression level to use for zstd or xz.
+          Compression level to use for gzip, zstd or xz.
+          For gzip: 1-9 (note: if compression level is also specified in gzipOptions, the gzipOptions value will be overwritten)
           For zstd: 1-19
           For xz: 0-9
-          Ignored for gzip (use gzipOptions instead)
         '';
       };
 
@@ -140,6 +141,7 @@ in
         description = ''
           Command line options to use when invoking `gzip`.
           Only used when compression is set to "gzip".
+          If compression level is specified both here and in compressionLevel, the compressionLevel value will take precedence.
         '';
       };
     };
@@ -156,7 +158,7 @@ in
             rangeMsg = {
               "zstd" = "zstd compression level must be between 1 and 19";
               "xz" = "xz compression level must be between 0 and 9";
-              "gzip" = "gzip does not support compression level option, use gzipOptions instead";
+              "gzip" = "gzip compression level must be between 1 and 9";
             };
           in
           rangeMsg.${cfg.compression};