data-mesher: init module

Co-authored-by: Brian McGee <brian@bmcgee.ie>

clanModules/data-mesher/shared.nix

@@ -0,0 +1,154 @@
+{
+  config,
+  lib,
+  ...
+}:
+let
+  cfg = config.clan.data-mesher;
+  dmLib = import ./lib.nix lib;
+
+  # the default bootstrap nodes are any machines with the admin or signers role
+  # we iterate through those machines, determining an IP address for them based on their VPN
+  # currently only supports zerotier
+  defaultBootstrapNodes = builtins.foldl' (
+    urls: name:
+    if
+      builtins.pathExists "${config.clan.core.settings.directory}/machines/${name}/facts/zerotier-ip"
+    then
+      let
+        ip = builtins.readFile "${config.clan.core.settings.directory}/machines/${name}/facts/zerotier-ip";
+      in
+      urls ++ "${ip}:${cfg.network.port}"
+    else
+      urls
+  ) [ ] (dmLib.machines config).bootstrap;
+in
+{
+  options.clan.data-mesher = {
+
+    bootstrapNodes = lib.mkOption {
+      type = lib.types.nullOr (lib.types.listOf lib.types.str);
+      default = null;
+      description = ''
+        A list of bootstrap nodes that act as an initial gateway when joining
+        the cluster.
+      '';
+      example = [
+        "192.168.1.1:7946"
+        "192.168.1.2:7946"
+      ];
+    };
+
+    network = {
+
+      interface = lib.mkOption {
+        type = lib.types.str;
+        description = ''
+          The interface over which cluster communication should be performed.
+          All the ip addresses associate with this interface will be part of
+          our host claim, including both ipv4 and ipv6.
+
+          This should be set to an internal/VPN interface.
+        '';
+        example = "tailscale0";
+      };
+
+      port = lib.mkOption {
+        type = lib.types.port;
+        default = 7946;
+        description = ''
+          Port to listen on for cluster communication.
+        '';
+      };
+    };
+  };
+
+  config = {
+
+    services.data-mesher = {
+      enable = true;
+      openFirewall = true;
+
+      settings = {
+        log_level = "warn";
+        state_dir = "/var/lib/data-mesher";
+
+        # read network id from vars
+        network.id = config.clan.core.vars.generators.data-mesher-network-key.files.public_key.value;
+
+        host = {
+          names = [ config.networking.hostName ];
+          key_path = config.clan.core.vars.generators.data-mesher-host-key.files.private_key.path;
+        };
+
+        cluster = {
+          port = cfg.network.port;
+          join_interval = "30s";
+          push_pull_interval = "30s";
+
+          interface = cfg.network.interface;
+          bootstrap_nodes = cfg.bootstrapNodes or defaultBootstrapNodes;
+        };
+
+        http.port = 7331;
+        http.interface = "lo";
+      };
+    };
+
+    # Generate host key.
+    clan.core.vars.generators.data-mesher-host-key = {
+      files =
+        let
+          owner = config.users.users.data-mesher.name;
+        in
+        {
+          private_key = {
+            inherit owner;
+          };
+          public_key = {
+            inherit owner;
+            secret = false;
+          };
+        };
+
+      runtimeInputs = [
+        config.services.data-mesher.package
+      ];
+
+      script = ''
+        data-mesher generate keypair \
+            --public-key-path $out/public_key \
+            --private-key-path $out/private_key
+      '';
+    };
+
+    clan.core.vars.generators.data-mesher-network-key = {
+      # generated once per clan
+      share = true;
+
+      files =
+        let
+          owner = config.users.users.data-mesher.name;
+        in
+        {
+          private_key = {
+            inherit owner;
+          };
+          public_key = {
+            inherit owner;
+            secret = false;
+          };
+        };
+
+      runtimeInputs = [
+        config.services.data-mesher.package
+      ];
+
+      script = ''
+        data-mesher generate keypair \
+            --public-key-path $out/public_key \
+            --private-key-path $out/private_key
+      '';
+    };
+  };
+}