nix-config/hosts/idols-aquamarine/monitoring/victoriametrics.nix

{
  lib,
  myvars,
  ...
}: {
  # Workaround for victoriametrics to store data in another place
  # https://www.freedesktop.org/software/systemd/man/latest/tmpfiles.d.html#Type
  systemd.tmpfiles.rules = [
    "D /data/apps/victoriametrics 0751 victoriametrics victoriametrics - -"
    "L+ /var/lib/victoriametrics - - - - /data/apps/victoriametrics"
  ];

  # https://victoriametrics.io/docs/victoriametrics/latest/configuration/configuration/
  services.my-victoriametrics = {
    enable = true;
    listenAddress = "127.0.0.1";
    port = 9090;
    retentionTime = "30d";

    extraFlags = [
      # Allowed percent of system memory VictoriaMetrics caches may occupy.
      "-memory.allowedPercent=50"
    ];
    # Directory below /var/lib to store victoriametrics metrics data.
    stateDir = "victoriametrics";

    # specifies a set of targets and parameters describing how to scrape metrics from them.
    # https://prometheus.io/docs/prometheus/latest/configuration/configuration/#scrape_config
    scrapeConfigs =
      [
        # --- Homelab Applications --- #

        {
          job_name = "dnsmasq-exporter";
          scrape_interval = "30s";
          metrics_path = "/metrics";
          static_configs = [
            {
              targets = ["${myvars.networking.hostsAddr.suzi.ipv4}:9153"];
              labels.type = "app";
              labels.app = "dnsmasq";
              labels.host = "suzi";
            }
          ];
        }

        {
          job_name = "v2ray-exporter";
          scrape_interval = "30s";
          metrics_path = "/metrics";
          static_configs = [
            {
              targets = ["${myvars.networking.hostsAddr.aquamarine.ipv4}:9153"];
              labels.type = "app";
              labels.app = "v2ray";
              labels.host = "aquamarine";
            }
          ];
        }
        {
          job_name = "postgres-exporter";
          scrape_interval = "30s";
          metrics_path = "/metrics";
          static_configs = [
            {
              targets = ["${myvars.networking.hostsAddr.aquamarine.ipv4}:9187"];
              labels.type = "app";
              labels.app = "postgresql";
              labels.host = "aquamarine";
            }
          ];
        }
        {
          job_name = "sftpgo-embedded-exporter";
          scrape_interval = "30s";
          metrics_path = "/metrics";
          static_configs = [
            {
              targets = ["${myvars.networking.hostsAddr.aquamarine.ipv4}:10000"];
              labels.type = "app";
              labels.app = "sftpgo";
              labels.host = "aquamarine";
            }
          ];
        }
      ]
      # --- Hosts --- #
      ++ (
        lib.attrsets.foldlAttrs
        (acc: hostname: addr:
          acc
          ++ [
            {
              job_name = "node-exporter-${hostname}";
              scrape_interval = "30s";
              metrics_path = "/metrics";
              static_configs = [
                {
                  # All my NixOS hosts.
                  targets = ["${addr.ipv4}:9100"];
                  labels.type = "node";
                  labels.host = hostname;
                }
              ];
            }
          ])
        []
        myvars.networking.hostsAddr
      );
  };

  services.vmalert = {
    enable = true;
    settings = {
      "datasource.url" = "http://localhost:9090";
      "notifier.url" = ["http://localhost:9093"]; # alertmanager's api

      # Whether to disable long-lived connections to the datasource.
      "datasource.disableKeepAlive" = true;
      # Whether to avoid stripping sensitive information such as auth headers or passwords
      # from URLs in log messages or UI and exported metrics.
      "datasource.showURL" = false;
      rule = [
        ./alert_rules/node-exporter.yml
        ./alert_rules/kubestate-exporter.yml
        ./alert_rules/etcd_embedded-exporter.yml
        ./alert_rules/istio_embedded-exporter.yml
        ./alert_rules/coredns_embedded-exporter.yml
      ];
    };
  };
}