pgscv: init package + module (#386064)

nixos/modules/module-list.nix

@@ -962,6 +962,7 @@
   ./services/monitoring/opentelemetry-collector.nix
   ./services/monitoring/osquery.nix
   ./services/monitoring/parsedmarc.nix
+  ./services/monitoring/pgscv.nix
   ./services/monitoring/prometheus/alertmanager-gotify-bridge.nix
   ./services/monitoring/prometheus/alertmanager-irc-relay.nix
   ./services/monitoring/prometheus/alertmanager-webhook-logger.nix

nixos/modules/services/monitoring/pgscv.nix

@@ -0,0 +1,75 @@
+{
+  config,
+  lib,
+  pkgs,
+  utils,
+  ...
+}:
+
+let
+  inherit (lib)
+    mkEnableOption
+    mkIf
+    mkOption
+    mkPackageOption
+    types
+    ;
+
+  cfg = config.services.pgscv;
+
+  settingsFormat = pkgs.formats.yaml { };
+  configFile = settingsFormat.generate "config.yaml" cfg.settings;
+in
+{
+  options.services.pgscv = {
+    enable = mkEnableOption "pgSCV, a PostgreSQL ecosystem metrics collector";
+
+    package = mkPackageOption pkgs "pgscv" { };
+
+    logLevel = mkOption {
+      type = types.enum [
+        "debug"
+        "info"
+        "warn"
+        "error"
+      ];
+      default = "info";
+      description = "Log level for pgSCV.";
+    };
+
+    settings = mkOption {
+      type = settingsFormat.type;
+      default = { };
+      description = ''
+        Configuration for pgSCV, in YAML format.
+
+        See [configuration reference](https://github.com/cherts/pgscv/wiki/Configuration-settings-reference).
+      '';
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.pgscv = {
+      description = "pgSCV - PostgreSQL ecosystem metrics collector";
+      wantedBy = [ "multi-user.target" ];
+      requires = [ "network-online.target" ];
+      after = [ "network-online.target" ];
+      path = [ pkgs.glibc ]; # shells out to getconf
+
+      serviceConfig = {
+        User = "postgres";
+        Group = "postgres";
+        ExecStart = utils.escapeSystemdExecArgs [
+          (lib.getExe cfg.package)
+          "--log-level=${cfg.logLevel}"
+          "--config-file=${configFile}"
+        ];
+        KillMode = "control-group";
+        TimeoutSec = 5;
+        Restart = "on-failure";
+        RestartSec = 10;
+        OOMScoreAdjust = 1000;
+      };
+    };
+  };
+}

pkgs/by-name/pg/pgscv/package.nix

@@ -0,0 +1,43 @@
+{
+  lib,
+  buildGoModule,
+  fetchFromGitHub,
+}:
+
+buildGoModule rec {
+  pname = "pgscv";
+  version = "0.13.0";
+
+  src = fetchFromGitHub {
+    owner = "CHERTS";
+    repo = "pgscv";
+    tag = "v${version}";
+    hash = "sha256-6qhJZHyVtEI4+pqi0dgagDC2RaISV9g/ygrezJO57Sk=";
+  };
+
+  vendorHash = "sha256-KahDpLwk+6KXaIfvjr7+nkFuEV4Dw3pyshkJ5XUEdUg=";
+
+  ldflags = [
+    "-X=main.appName=pgscv"
+    "-X=main.gitTag=${src.tag}"
+    "-X=main.gitCommit=${src.tag}"
+    "-X=main.gitBranch=${src.tag}"
+  ];
+
+  # tests rely on a pretty complex Postgres setup
+  doCheck = false;
+
+  postInstall = ''
+    mv $out/bin/{cmd,pgscv}
+  '';
+
+  meta = {
+    description = "PgSCV is a PostgreSQL ecosystem metrics collector";
+    homepage = "https://github.com/CHERTS/pgscv/";
+    changelog = "https://github.com/CHERTS/pgscv/releases/${version}";
+    license = lib.licenses.bsd3;
+    platforms = lib.platforms.linux;
+    maintainers = with lib.maintainers; [ k900 ];
+    mainProgram = "pgscv";
+  };
+}