nixos/netdata: introduce recommendedPythonPackages

This option furthers the "zero configuration" reputation of netdata by collecting
some Python packages available in nixpkgs and offering them to the module.

It is disabled by default.

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>

nixos/modules/services/monitoring/netdata.nix

@@ -89,6 +89,14 @@ in {
             Whether to enable python-based plugins
           '';
         };
+        recommendedPythonPackages = mkOption {
+          type = types.bool;
+          default = false;
+          description = lib.mdDoc ''
+            Whether to enable a set of recommended Python plugins
+            by installing extra Python packages.
+          '';
+        };
         extraPackages = mkOption {
           type = types.functionTo (types.listOf types.package);
           default = ps: [];
@@ -201,6 +209,17 @@ in {
         }
       ];
 
+    # Includes a set of recommended Python plugins in exchange of imperfect disk consumption.
+    services.netdata.python.extraPackages = lib.mkIf cfg.python.recommendedPythonPackages (ps: [
+      ps.requests
+      ps.pandas
+      ps.numpy
+      ps.psycopg2
+      ps.python-ldap
+      ps.netdata-pandas
+      ps.changefinder
+    ]);
+
     services.netdata.configDir.".opt-out-from-anonymous-statistics" = mkIf (!cfg.enableAnalyticsReporting) (pkgs.writeText ".opt-out-from-anonymous-statistics" "");
     environment.etc."netdata/netdata.conf".source = configFile;
     environment.etc."netdata/conf.d".source = configDirectory;