Refactor common modules.

common/consul.nix

@@ -1,44 +1,47 @@
-{ pkgs, config, ... }:
+{ pkgs, config, lib, ... }:
 let
   servers = [
     "c1"
     "c2"
     "c3"
   ];
-  server_enabled = builtins.elem config.networking.hostName servers;
 in
 {
-  services.consul = {
-    enable = true;
-    webUi = true;
-    interface.advertise = "eno1";
-    extraConfig = {
-      client_addr = "0.0.0.0";
-      datacenter = "alo";
-      server = server_enabled;
-      bootstrap_expect = if server_enabled then (builtins.length servers + 2) / 2 else null;
-      retry_join = builtins.filter (elem: elem != config.networking.hostName) servers;
+  options.clusterRole.consulServer = lib.mkEnableOption "Consul server mode";
+
+  config = {
+    services.consul = {
+      enable = true;
+      webUi = true;
+      interface.advertise = "eno1";
+      extraConfig = {
+        client_addr = "0.0.0.0";
+        datacenter = "alo";
+        server = config.clusterRole.consulServer;
+        bootstrap_expect = if config.clusterRole.consulServer then (builtins.length servers + 2) / 2 else null;
+        retry_join = builtins.filter (elem: elem != config.networking.hostName) servers;
       telemetry = {
         prometheus_retention_time = "24h";
         disable_hostname = true;
       };
     };
-  };
+    };
 
-  environment.persistence."/persist".directories = [ "/var/lib/consul" ];
+    environment.persistence."/persist".directories = [ "/var/lib/consul" ];
 
-  networking.firewall = {
-    allowedTCPPorts = [
-      8600
-      8500
-      8301
-      8302
-      8300
-    ];
-    allowedUDPPorts = [
-      8600
-      8301
-      8302
-    ];
+    networking.firewall = {
+      allowedTCPPorts = [
+        8600
+        8500
+        8301
+        8302
+        8300
+      ];
+      allowedUDPPorts = [
+        8600
+        8301
+        8302
+      ];
+    };
   };
 }