nixos-config/modules/grafana/default.nix

{ pkgs, config, ... }:
{
  services.nginx.virtualHosts.${config.services.grafana.settings.server.domain} = {
    forceSSL = true;
    enableACME = true;

    locations."/" = {
      proxyPass = "http://${toString config.services.grafana.settings.server.http_addr}:${toString config.services.grafana.settings.server.http_port}";

      proxyWebsockets = true;

      extraConfig = ''
        proxy_pass_header Authorization;
      '';
    };
  };

  services.grafana = {
    enable = true;

    settings = {
      server = {
        domain = "grafana.katkak.dev";
        http_addr = "127.0.0.1";
        http_port = 2342;
      };
    };

    provision = {
      datasources.settings.datasources = [
        {
          name = "Prometheus";
          type = "prometheus";
          url = "http://${config.services.prometheus.listenAddress}:${toString config.services.prometheus.port}";
        }
        {
          name = "Loki";
          type = "loki";
          url = "http://${config.services.loki.configuration.server.http_listen_address}:${toString config.services.loki.configuration.server.http_listen_port}";
        }
      ];
    };
  };

  services.prometheus = {
    enable = true;

    port = 9001;

    exporters = {
      node = {
        enable = true;

        enabledCollectors = [ "systemd" ];

        port = 9002;
      };
    };

    scrapeConfigs = [
      {
        job_name = "nixos";

        static_configs = [
          {
            targets = [
              "127.0.0.1:${toString config.services.prometheus.exporters.node.port}"
            ];
          }
        ];
      }
    ];
  };

  services.loki = {
    enable = true;

    configuration = {
      server = {
        http_listen_port = 3100;
        http_listen_address = "127.0.0.1";
      };

      auth_enabled = false;

      common = {
        instance_addr = "127.0.0.1";
        path_prefix = "/tmp/loki";
        storage = {
          filesystem = {
            chunks_directory = "/var/lib/loki/chunks";
            rules_directory = "/var/lib/loki/rules";
          };
        };
        replication_factor = 1;
        ring = {
          kvstore = {
            store = "inmemory";
          };
        };
      };

      ingester = {
        lifecycler = {
          address = "127.0.0.1";

          ring = {
            kvstore = {
              store = "inmemory";
            };

            replication_factor = 1;
          };

          final_sleep = "0s";
        };

        chunk_idle_period = "1h";
        max_chunk_age = "1h";
        chunk_target_size = 1048576;
        chunk_retain_period = "30s";
      };

      schema_config = {
        configs = [
          {
            from = "2025-10-20";
            store = "tsdb";
            object_store = "filesystem";
            schema = "v13";
            index = {
              prefix = "index_";
              period = "24h";
            };
          }
        ];
      };

      limits_config = {
        reject_old_samples = true;
        reject_old_samples_max_age = "168h";
      };

      table_manager = {
        retention_deletes_enabled = false;
        retention_period = "0s";
      };

      compactor = {
        working_directory = "/var/lib/loki";
        compactor_ring = {
          kvstore = {
            store = "inmemory";
          };
        };
      };
    };
  };

  services.promtail = {
    enable = true;

    configuration = {
      server = {
        http_listen_port = 28183;
        grpc_listen_port = 0;
      };

      positions = {
        filename = "/tmp/positions.yaml";
      };

      clients = [
        {
          url = "http://127.0.0.1:${toString config.services.loki.configuration.server.http_listen_port}/loki/api/v1/push";
        }
      ];

      scrape_configs = [
        {
          job_name = "journal";
          journal = {
            max_age = "12h";
            labels = {
              job = "systemd-journal";
              host = "homelab";
            };
          };
          relabel_configs = [
            {
              source_labels = [ "__journal__systemd_unit" ];
              target_label = "unit";
            }
          ];
        }
      ];
    };
  };
}