feat(pharos): add Pharos service configuration and module

Author: monyarm

modules/default.nix

@@ -7,5 +7,6 @@
     ./random-alerts
     ./host-info.nix
     ./secrets.nix
+    ./pharos
   ];
 }

modules/pharos/default.nix

@@ -0,0 +1,78 @@
+{ ... }:
+{
+  flake.modules.nixos.pharos =
+    {
+      config,
+      lib,
+      pkgs,
+      ...
+    }:
+    let
+      cfg = config.services.pharos;
+      images = {
+        "testnet" = {
+          image = "public.ecr.aws/k2g7b7g1/pharos/testnet";
+          tag = "63b85b6b";
+          digest = "sha256:547a8519a11ab455871594580f7f5342863fb84d4a07c936969afe05f3aab358";
+          sha256 = "sha256-WNCWeoQnT7TLmVQY+NuMtOXBtJ8TFlSNCekNWX90gDk=";
+        };
+        "devnet" = {
+          image = "public.ecr.aws/k2g7b7g1/pharos";
+          tag = "latest";
+          digest = "sha256:82c7d84fc7d7f17056e947030c4a67bf23a139fe19539a6b237ab42df8215e7b";
+          sha256 = "1lh9hna57y9n3h0lhmvy8grlg02caq6p1k9whgwp0av67wllk5km";
+        };
+      };
+    in
+    {
+      options.services.pharos = with lib; {
+        enable = mkEnableOption (lib.mdDoc "Pharos");
+        network = mkOption {
+          type = types.enum [
+            "testnet"
+            "devnet"
+            "mainnet"
+          ];
+          default = "testnet";
+          description = "Network to connect to";
+        };
+      };
+      config = {
+        virtualisation.oci-containers.containers."pharos-${cfg.network}" = {
+          # In order to get the hash and digest of the image, use:
+          # nix run nixpkgs#nix-prefetch-docker -- --image-name  'public.ecr.aws/k2g7b7g1/pharos' --image-tag latest
+          # The url can be found in the pharos documentation
+          # https://docs.pharosnetwork.xyz/node-and-validator-guide/validator-node-deployment/using-docker-testnet
+          # https://docs.pharosnetwork.xyz/node-and-validator-guide/validator-node-deployment/using-docker-devnet
+          image = with images."${cfg.network}"; "${image}:${tag}";
+
+          imageFile =
+            with images."${cfg.network}";
+            pkgs.dockerTools.pullImage {
+              imageName = image;
+              imageDigest = digest;
+              sha256 = sha256;
+              finalImageName = image;
+              finalImageTag = tag;
+            };
+          volumes = [
+            "/var/lib/pharos-${cfg.network}:/data"
+          ];
+          ports = [
+            "18100:18100"
+            "18200:18200"
+            "19000:19000"
+          ];
+        };
+        assertions = [
+          {
+            assertion = cfg.network != "mainnet";
+            message = "Pharos is not available on mainnet yet";
+          }
+        ];
+        systemd.tmpfiles.rules = [
+          "d /var/lib/pharos-${cfg.network} 0700 root root - -"
+        ];
+      };
+    };
+}