1 files changed, 145 insertions, 0 deletions
diff --git a/nixos/modules/services/monitoring/prometheus/exporters/pgbouncer.nix b/nixos/modules/services/monitoring/prometheus/exporters/pgbouncer.nix
new file mode 100644
index 00000000000..9e55cadae52
--- /dev/null
+++ b/nixos/modules/services/monitoring/prometheus/exporters/pgbouncer.nix
@@ -0,0 +1,145 @@
+{ config, lib, pkgs, options }:
+
+with lib;
+
+let
+  cfg = config.services.prometheus.exporters.pgbouncer;
+in
+{
+  port = 9127;
+  extraOpts = {
+
+    telemetryPath = mkOption {
+      type = types.str;
+      default = "/metrics";
+      description = lib.mdDoc ''
+        Path under which to expose metrics.
+      '';
+    };
+
+    connectionString = mkOption {
+      type = types.str;
+      default = "";
+      example = "postgres://admin:@localhost:6432/pgbouncer?sslmode=require";
+      description = lib.mdDoc ''
+        Connection string for accessing pgBouncer.
+
+        NOTE: You MUST keep pgbouncer as database name (special internal db)!!!
+
+        NOTE: Admin user (with password or passwordless) MUST exist
+        in the services.pgbouncer.authFile if authType other than any is used.
+
+        WARNING: this secret is stored in the world-readable Nix store!
+        Use {option}`connectionStringFile` instead.
+      '';
+    };
+
+    connectionStringFile = mkOption {
+      type = types.nullOr types.path;
+      default = null;
+      example = "/run/keys/pgBouncer-connection-string";
+      description = lib.mdDoc ''
+        File that contains pgBouncer connection string in format:
+        postgres://admin:@localhost:6432/pgbouncer?sslmode=require
+
+        NOTE: You MUST keep pgbouncer as database name (special internal db)!!!
+
+        NOTE: Admin user (with password or passwordless) MUST exist
+        in the services.pgbouncer.authFile if authType other than any is used.
+
+        {option}`connectionStringFile` takes precedence over {option}`connectionString`
+      '';
+    };
+
+    pidFile = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      description = lib.mdDoc ''
+        Path to PgBouncer pid file.
+
+        If provided, the standard process metrics get exported for the PgBouncer
+        process, prefixed with 'pgbouncer_process_...'. The pgbouncer_process exporter
+        needs to have read access to files owned by the PgBouncer process. Depends on
+        the availability of /proc.
+
+        https://prometheus.io/docs/instrumenting/writing_clientlibs/#process-metrics.
+
+      '';
+    };
+
+    webSystemdSocket = mkOption {
+      type = types.bool;
+      default = false;
+      description = lib.mdDoc ''
+        Use systemd socket activation listeners instead of port listeners (Linux only).
+      '';
+    };
+
+    logLevel = mkOption {
+      type = types.enum ["debug" "info" "warn" "error" ];
+      default = "info";
+      description = lib.mdDoc ''
+        Only log messages with the given severity or above.
+      '';
+    };
+
+    logFormat = mkOption {
+      type = types.enum ["logfmt" "json"];
+      default = "logfmt";
+      description = lib.mdDoc ''
+        Output format of log messages. One of: [logfmt, json]
+      '';
+    };
+
+    webConfigFile = mkOption {
+      type = types.nullOr types.path;
+      default = null;
+      description = lib.mdDoc ''
+        Path to configuration file that can enable TLS or authentication.
+      '';
+    };
+
+    extraFlags = mkOption {
+      type = types.listOf types.str;
+      default = [ ];
+      description = lib.mdDoc ''
+        Extra commandline options when launching Prometheus.
+      '';
+    };
+
+  };
+
+  serviceOpts = {
+    after = [ "pgbouncer.service" ];
+      serviceConfig = let
+      startScript = pkgs.writeShellScriptBin "pgbouncer-start" "${concatStringsSep " " ([
+            "${pkgs.prometheus-pgbouncer-exporter}/bin/pgbouncer_exporter"
+            "--web.listen-address ${cfg.listenAddress}:${toString cfg.port}"
+            "--pgBouncer.connectionString ${if cfg.connectionStringFile != null then
+            "$(head -n1 ${cfg.connectionStringFile})" else "${escapeShellArg cfg.connectionString}"}"
+          ]
+            ++ optionals (cfg.telemetryPath != null) [
+            "--web.telemetry-path ${escapeShellArg cfg.telemetryPath}"
+          ]
+            ++ optionals (cfg.pidFile != null) [
+            "--pgBouncer.pid-file= ${escapeShellArg cfg.pidFile}"
+          ]
+            ++ optionals (cfg.logLevel != null) [
+            "--log.level ${escapeShellArg cfg.logLevel}"
+          ]
+            ++ optionals (cfg.logFormat != null) [
+            "--log.format ${escapeShellArg cfg.logFormat}"
+          ]
+            ++ optionals (cfg.webSystemdSocket != false) [
+            "--web.systemd-socket ${escapeShellArg cfg.webSystemdSocket}"
+          ]
+            ++ optionals (cfg.webConfigFile != null) [
+            "--web.config.file ${escapeShellArg cfg.webConfigFile}"
+          ]
+            ++ cfg.extraFlags)}";
+      in
+      {
+        ExecStart = "${startScript}/bin/pgbouncer-start";
+      };
+  };
+}