feat: initial work on metacontroller

modules/metacontroller/compositecontroller.nix

@@ -0,0 +1,139 @@
+{ config, lib, ... }:
+
+with lib;
+
+{
+  options = {
+    parentResource = {
+      apiVersion = mkOption {
+        description = "Parent resource apiVersion";
+        type = types.str;
+        example = "apps/v1";
+      };
+
+      resource = mkOption {
+        description = "The canonical, lowercase, plural name of the parent resource";
+        type = types.str;
+        example = "deployments";
+      };
+
+      revisionHistory = mkOption {
+        description = "A list of field path strings specifying which parent fields trigger rolling updates of children";
+        type = types.listOf types.str;
+        default = ["spec"];
+        example = ["spec.template"];
+      };
+    };
+
+    childResources = mkOption {
+      description = "A list of resource rules specifying the child resources";
+      type = types.listOf (types.submodule ({ config, ... }: {
+        options = {
+          apiVersion = mkOption {
+            description = "The API group/version of the child resource, or just version for core APIs";
+            type = types.str;
+            example = "apps/v1";
+          };
+
+          resource = mkOption {
+            description = "The canonical, lowercase, plural name of the child resource";
+            type = types.str;
+            example = "deployments";
+          };
+
+          updateStrategy = {
+            method = mkOption {
+              description = ''
+                A string indicating the overall method that should be used for updating this type of child resource.
+                The default is OnDelete, which means don't try to update children that already exist.
+
+                - OnDelete: Don't update existing children unless they get deleted by some other agent.
+                - Recreate: Immediately delete any children that differ from the desired state, and recreate them in the desired state.
+                - InPlace: Immediately update any children that differ from the desired state.
+                - RollingRecreate: Delete each child that differs from the desired state, one at a time,
+                  and recreate each child before moving on to the next one.
+                  Pause the rollout if at any time one of the children that have already been updated fails one or more status checks.
+                - RollingInPlace: Update each child that differs from the desired state, one at a time. Pause the rollout if at any time
+                  one of the children that have already been updated fails one or more status checks.
+              '';
+              type = types.enum [
+                "OnDelete"
+                "Recreate"
+                "InPlace"
+                "RollingRecreate"
+                "RollingInPlace"
+              ];
+              default = "OnDelete";
+            };
+
+            statusChecks.conditions = mkOption {
+              description = ''
+                A list of status condition checks that must all pass on already-updated
+                children for the rollout to continue.
+              '';
+              type = types.listOf (types.submodule ({ config, ... }: {
+                options = {
+                  type = mkOption {
+                    description = "A string specifying the status condition type to check.";
+                    type = types.str;
+                  };
+
+                  status = mkOption {
+                    description = ''
+                      A string specifying the required status of the given status condition.
+                      If none is specified, the condition's status is not checked.
+                    '';
+                    type = types.str;
+                    default = "";
+                  };
+
+                  reason = mkOption {
+                    description = ''
+                      A string specifying the required reason of the given status condition.
+                      If none is specified, the condition's reason is not checked.
+                    '';
+                    type = types.str;
+                    default = "";
+                  };
+                };
+              }));
+              default = [];
+            };
+          };
+        };
+      }));
+      default = [];
+    };
+
+    resyncPeriodSeconds = mkOption {
+      description = ''
+        How often, in seconds, you want every parent object to be resynced,
+        even if no changes are detected.
+      '';
+      type = types.int;
+      default = 0;
+    };
+
+    generateSelector = mkOption {
+      description = ''
+        If true, ignore the selector in each parent object and instead generate
+        a unique selector that prevents overlap with other objects.
+      '';
+      type = types.bool;
+      default = false;
+    };
+
+    hooks = {
+      sync.webhook.url = mkOption {
+        description = "Webhook URL where to send sync request";
+        type = types.str;
+      };
+
+      finalize.webhook.url = mkOption {
+        description = "Webhook URL where to send finalize request";
+        type = types.str;
+        default = "";
+      };
+    };
+  };
+}

modules/metacontroller/default.nix

@@ -0,0 +1,36 @@
+{ config, lib, ... }:
+
+with lib;
+
+{
+  imports = [ ../k8s.nix ];
+
+  options.metacontroller = {
+    compositeControllers = mkOption {
+      type = types.attrsOf (types.submodule ({ name, config, ... }: {
+        imports = [ ./compositecontroller.nix ];
+
+        options = {
+          name = mkOption {
+            description = "Name of the composite controller";
+            type = types.str;
+            default = name;
+          };
+        };
+      }));
+      default = {};
+    };
+  };
+
+  config = {
+    kubernetes.customResources = [{
+      group = "metacontroller.k8s.io";
+      version = "v1alpha1";
+      kind = "CompositeController";
+      resource = "compositecontrollers";
+      description = "Composite controller";
+      alias = "compositecontrollers";
+      module.imports = [ ./compositecontroller.nix ];
+    }];
+  };
+}