1 files changed, 11 insertions, 2 deletions
diff --git a/nixos/shared/prometheus-sql-exporter/service.nix b/nixos/shared/prometheus-sql-exporter/service.nix
index a887f91..a79528c 100644
--- a/nixos/shared/prometheus-sql-exporter/service.nix
+++ b/nixos/shared/prometheus-sql-exporter/service.nix
@@ -4,7 +4,16 @@
 let
   sqlExporter = pkgs.callPackage ./default.nix {};
   cfg = config.services.prometheus-sql-exporter;
-  configFile =  builtins.toFile "config.yaml" (builtins.toJSON cfg.config);
+  configFile = builtins.toFile "config.yaml" (builtins.toJSON cfg.config);
+  validateConfig = file:
+    pkgs.runCommand "validate-config"
+      {
+        nativeBuildInputs = [sqlExporter];
+      }
+      ''
+        sql_exporter -config.check -config.file "${file}"
+        ln -s "${file}" "$out"
+      '';
 in
 {
   options.services.prometheus-sql-exporter = {
@@ -20,7 +29,7 @@ in
   config = lib.mkIf cfg.enable {
     systemd.services.prometheus-sql-exporter = {
       serviceConfig = {
-        ExecStart = "${sqlExporter}/bin/sql_exporter -config.file ${configFile} -web.listen-address :${toString cfg.port}";
+        ExecStart = "${sqlExporter}/bin/sql_exporter -config.file ${validateConfig configFile} -web.listen-address :${toString cfg.port}";
         DynamicUser = "true";
         User = "prometheus-sql-exporter";
       };