feat: move away from cube host

hosts/best/grafana/prometheus.nix

@@ -0,0 +1,44 @@
+{ self, config, lib, ... }: let
+  inherit (lib) enabled filterAttrs flatten mapAttrsToList;
+in {
+  services.grafana.provision.datasources.settings = {
+    datasources = [{
+      name = "Prometheus";
+      type = "prometheus";
+      url  = "http://[::1]:${toString config.services.prometheus.port}";
+
+      orgId = 1;
+    }];
+
+    deleteDatasources = [{
+      name  = "Prometheus";
+      orgId = 1;
+    }];
+  };
+
+  services.prometheus = enabled {
+    listenAddress = "[::]";
+    retentionTime = "1w";
+
+    scrapeConfigs = let
+      configToScrapeConfig = hostName: { config, ... }: let
+        hostConfig = config;
+      in hostConfig.services.prometheus.exporters
+        |> filterAttrs (exporterName: exporterConfig:
+          exporterName != "minio" &&
+          exporterName != "unifi-poller" &&
+          exporterName != "tor" &&
+          exporterConfig.enable or false)
+        |> mapAttrsToList (exporterName: exporterConfig: {
+          job_name = "${exporterName}-${hostName}";
+
+          static_configs = [{
+            targets = [ "${hostName}:${toString exporterConfig.port}" ];
+          }];
+        });
+
+    in self.nixosConfigurations
+    |> mapAttrsToList configToScrapeConfig
+    |> flatten;
+  };
+}