From 196c62b5e24dada5c8292b00088b072819a754c9 Mon Sep 17 00:00:00 2001
From: Max <max@privatevoid.net>
Date: Sun, 4 Aug 2024 23:39:00 +0200
Subject: [PATCH] cluster/services/incandescence: init

---
 cluster/services/incandescence/default.nix    |  19 +++
 cluster/services/incandescence/options.nix    |  22 +++
 .../incandescence/provider-options.nix        |  72 ++++++++++
 cluster/services/incandescence/provider.nix   | 128 ++++++++++++++++++
 4 files changed, 241 insertions(+)
 create mode 100644 cluster/services/incandescence/default.nix
 create mode 100644 cluster/services/incandescence/options.nix
 create mode 100644 cluster/services/incandescence/provider-options.nix
 create mode 100644 cluster/services/incandescence/provider.nix

diff --git a/cluster/services/incandescence/default.nix b/cluster/services/incandescence/default.nix
new file mode 100644
index 0000000..e24ed01
--- /dev/null
+++ b/cluster/services/incandescence/default.nix
@@ -0,0 +1,19 @@
+{ config, ... }:
+
+{
+  imports = [
+    ./options.nix
+  ];
+
+  services.incandescence = {
+    nodes = {
+      provider = config.services.consul.nodes.agent;
+    };
+    nixos = {
+      provider = [
+        ./provider.nix
+        ./provider-options.nix
+      ];
+    };
+  };
+}
diff --git a/cluster/services/incandescence/options.nix b/cluster/services/incandescence/options.nix
new file mode 100644
index 0000000..99ab4ad
--- /dev/null
+++ b/cluster/services/incandescence/options.nix
@@ -0,0 +1,22 @@
+{ lib, ... }:
+
+let
+  inherit (lib) mkOption;
+  inherit (lib.types) attrsOf listOf submodule str;
+in
+
+{
+  options.incandescence = {
+    providers = mkOption {
+      type = attrsOf (submodule ({ name, ... }: {
+        options = {
+          objects = mkOption {
+            type = attrsOf (listOf str);
+            default = { };
+          };
+        };
+      }));
+      default = { };
+    };
+  };
+}
diff --git a/cluster/services/incandescence/provider-options.nix b/cluster/services/incandescence/provider-options.nix
new file mode 100644
index 0000000..9cc652d
--- /dev/null
+++ b/cluster/services/incandescence/provider-options.nix
@@ -0,0 +1,72 @@
+{ lib, ... }:
+
+let
+  inherit (lib) mkEnableOption mkOption;
+  inherit (lib.types) attrsOf functionTo ints listOf nullOr package submodule str;
+in
+
+{
+  options.services.incandescence = {
+    providers = mkOption {
+      type = attrsOf (submodule ({ name, ... }: {
+        options = {
+          locksmith = mkEnableOption "Locksmith integration";
+
+          wantedBy = mkOption {
+            type = listOf str;
+          };
+
+          partOf = mkOption {
+            type = listOf str;
+          };
+
+          wants = mkOption {
+            type = listOf str;
+            default = [ ];
+          };
+
+          after = mkOption {
+            type = listOf str;
+            default = [ ];
+          };
+
+          packages = mkOption {
+            type = listOf package;
+            default = [ ];
+          };
+
+          formulae = mkOption {
+            type = attrsOf (submodule ({ ... }: {
+              options = {
+                deps = mkOption {
+                  type = listOf str;
+                  default = [ ];
+                };
+
+                create = mkOption {
+                  type = functionTo str;
+                };
+
+                change = mkOption {
+                  type = nullOr (functionTo str);
+                  default = null;
+                };
+
+                destroy = mkOption {
+                  type = str;
+                };
+
+                destroyAfterDays = mkOption {
+                  type = ints.unsigned;
+                  default = 0;
+                };
+              };
+            }));
+            default = { };
+          };
+        };
+      }));
+      default = { };
+    };
+  };
+}
diff --git a/cluster/services/incandescence/provider.nix b/cluster/services/incandescence/provider.nix
new file mode 100644
index 0000000..b3fa989
--- /dev/null
+++ b/cluster/services/incandescence/provider.nix
@@ -0,0 +1,128 @@
+{ cluster, config, lib, ... }:
+
+let
+  inherit (lib) concatStringsSep escapeShellArg flatten filter filterAttrs length mapAttrs mapAttrs' mapAttrsToList mkIf mkMerge pipe stringToCharacters;
+
+  cfg = config.services.incandescence;
+  clusterCfg = cluster.config.incandescence;
+in
+
+{
+  systemd.services = pipe cfg.providers [
+    (mapAttrsToList (provider: providerConfig: pipe providerConfig.formulae [
+      (mapAttrsToList (formula: formulaConfig: let
+        kvRoot = "services/incandescence/providers/${provider}/formulae/${formula}";
+        time = "$(date +%s)";
+      in {
+        "ignite-${provider}-${formula}-create" = {
+          description = "Ignite Creation: ${provider} - ${formula}";
+          wantedBy = [ "incandescence-${provider}.target" ];
+          before = [ "incandescence-${provider}.target" ];
+          wants = providerConfig.wants ++ map (dep: "ignite-${provider}-${dep}-create.service") formulaConfig.deps;
+          after = providerConfig.after ++ map (dep: "ignite-${provider}-${dep}-create.service") formulaConfig.deps;
+          serviceConfig.Type = "oneshot";
+          distributed.enable = true;
+          path = [ config.services.consul.package ] ++ providerConfig.packages;
+          script = pipe clusterCfg.providers.${provider}.objects.${formula} [
+            (map (object: ''
+              if ! consul kv get ${kvRoot}/${object}/alive >/dev/null; then
+                echo "Create ${formula}: ${object}"
+                if (
+                ${formulaConfig.create object}
+                )
+                then
+                  consul kv put ${kvRoot}/${object}/alive true
+                  consul kv delete ${kvRoot}/${object}/destroyOn
+                else
+                  echo "Creation failed: ${object}"
+                fi
+              fi
+            ''))
+            (concatStringsSep "\n")
+          ];
+        };
+        "ignite-${provider}-${formula}-change" = mkIf (formulaConfig.change != null) {
+          description = "Ignite Change: ${provider} - ${formula}";
+          wantedBy = [ "incandescence-${provider}.target" ];
+          before = [ "incandescence-${provider}.target" ];
+          wants = providerConfig.wants ++ [ "ignite-${provider}-${formula}-create.service" ] ++ map (dep: "ignite-${provider}-${dep}-change.service") formulaConfig.deps;
+          after = providerConfig.after ++ [ "ignite-${provider}-${formula}-create.service" ] ++ map (dep: "ignite-${provider}-${dep}-change.service") formulaConfig.deps;
+          serviceConfig.Type = "oneshot";
+          distributed.enable = true;
+          path = [ config.services.consul.package ] ++ providerConfig.packages;
+          script = pipe clusterCfg.providers.${provider}.objects.${formula} [
+            (map (object: ''
+              echo "Change ${formula}: ${object}"
+              (
+              ${formulaConfig.change object}
+              ) || echo "Change failed: ${object}"
+            ''))
+            (concatStringsSep "\n")
+          ];
+        };
+        "ignite-${provider}-${formula}-destroy" = {
+          description = "Ignite Destruction: ${provider} - ${formula}";
+          wantedBy = [ "incandescence-${provider}.target" ] ++ map (dep: "ignite-${provider}-${dep}-destroy.service") formulaConfig.deps;
+          before = [ "incandescence-${provider}.target" ] ++ map (dep: "ignite-${provider}-${dep}-destroy.service") formulaConfig.deps;
+          wants = providerConfig.wants ++ [ "ignite-${provider}-${formula}-change.service" ];
+          after = providerConfig.after ++ [ "ignite-${provider}-${formula}-change.service" ];
+          serviceConfig.Type = "oneshot";
+          distributed.enable = true;
+          path = [ config.services.consul.package ] ++ providerConfig.packages;
+          script = let
+            fieldNum = pipe kvRoot [
+              stringToCharacters
+              (filter (x: x == "/"))
+              length
+              (builtins.add 2)
+              toString
+            ];
+            keyFilter = pipe clusterCfg.providers.${provider}.objects.${formula} [
+              (map (x: escapeShellArg "^${x}$"))
+              (concatStringsSep " \\\n  -e ")
+            ];
+            destroyAfterDays = toString formulaConfig.destroyAfterDays;
+          in ''
+            consul kv get --keys ${kvRoot}/ | cut -d/ -f${fieldNum} | grep -v -e ${keyFilter} | while read object; do
+              if consul kv get ${kvRoot}/$object/alive >/dev/null; then
+                destroyOn="$(consul kv get ${kvRoot}/$object/destroyOn || true)"
+                if [[ -z "$destroyOn" && "${destroyAfterDays}" -ne 0 ]]; then
+                  echo "Schedule ${formula} for destruction in ${destroyAfterDays} days: $object"
+                  consul kv put ${kvRoot}/$object/destroyOn "$((${time} + 86400 * ${destroyAfterDays}))"
+                elif [[ "${destroyAfterDays}" -eq 0 || "${time}" -ge "$destroyOn" ]]; then
+                  echo "Destroy ${formula}: $object"
+                  export OBJECT="$object"
+                  if (
+                  ${formulaConfig.destroy}
+                  )
+                  then
+                    consul kv delete --recurse ${kvRoot}/$object
+                  else
+                    echo "Destruction failed: $object"
+                  fi
+                else
+                  echo "Scheduled for destruction on $destroyOn (now: ${time})"
+                fi
+              fi
+            done
+          '';
+        };
+      }))
+    ]))
+    flatten
+    mkMerge
+  ];
+
+  systemd.targets = mapAttrs' (provider: providerConfig: {
+    name = "incandescence-${provider}";
+    value = {
+      description = "An Incandescence | ${provider}";
+      inherit (providerConfig) wantedBy partOf;
+    };
+  }) cfg.providers;
+
+  services.locksmith.providers = mapAttrs (provider: providerConfig: {
+    wantedBy = [ "incandescence-${provider}.target" ];
+    after = [ "incandescence-${provider}.target" ];
+  }) (filterAttrs (_: providerConfig: providerConfig.locksmith) cfg.providers);
+}