Use declaritive system for creating singletons

- Let the code say the requirements of each singleton is instead of
  comments

Signed-off-by: Sebastian Malton <sebastian@malton.name>

src/common/utils/singleton.ts

@@ -19,6 +19,7 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+
 type StaticThis<T, R extends any[]> = { new(...args: R): T };
 
 export class Singleton {
@@ -88,3 +89,124 @@ export class Singleton {
 }
 
 export default Singleton;
+
+export interface DeclareOpts {
+  requires?: Iterable<typeof Singleton>,
+}
+
+type Initializer<T> = (instance: T) => void;
+
+interface CreateRequirements {
+  builds: typeof Singleton,
+  args?: ConstructorParameters<typeof Singleton> | (() => ConstructorParameters<typeof Singleton>),
+  requires?: Set<typeof Singleton>,
+  init?: (single: Singleton) => Promise<void>;
+}
+
+/**
+ * A builder class for declaring the dependency graph of a set of singletons
+ *
+ * This is useful because it allows the code to declare the requirements
+ */
+export class CreateSingletons {
+  #requirements: CreateRequirements[] = [];
+
+  private constructor() {
+    //
+  }
+
+  static begin(): CreateSingletons {
+    return new CreateSingletons();
+  }
+
+  /**
+   * Add a Singleton that requires no arguments to build
+   * @param builds The constructor which must be a type that extends Singleton
+   * @param opts The optional singletons that must be required before this can be created
+   * @returns the builder
+   */
+  declare<T>(builds: StaticThis<T, []>, opts?: DeclareOpts): this;
+  declare<T>(builds: StaticThis<T, []>, init?: Initializer<T>, opts?: DeclareOpts): this;
+  declare<T>(builds: StaticThis<T, []>, initOrOpts?: Initializer<T> | DeclareOpts, opts?: DeclareOpts): this {
+    if (typeof initOrOpts === "function") {
+      const { requires } = opts ?? {};
+
+      this.#requirements.push({
+        builds: builds as any,
+        requires: new Set(requires),
+        init: initOrOpts as any,
+      });
+    } else {
+      const { requires } = initOrOpts ?? {};
+
+      this.#requirements.push({
+        builds: builds as any,
+        requires: new Set(requires),
+      });
+    }
+
+    return this;
+  }
+
+  /**
+   * Like `declare` but with the ability to pass in arguments for the constructor
+   */
+  declareWithArgs<T, R extends any[]>(builds: StaticThis<T, R>, args: R | (() => R), opts?: DeclareOpts): this;
+  declareWithArgs<T, R extends any[]>(builds: StaticThis<T, R>, args: R | (() => R), init?: Initializer<T>, opts?: DeclareOpts): this;
+  declareWithArgs<T, R extends any[]>(builds: StaticThis<T, R>, args: R | (() => R), initOrOpts?: Initializer<T> | DeclareOpts, opts?: DeclareOpts): this {
+    if (typeof initOrOpts === "function") {
+      const { requires } = opts ?? {};
+
+      this.#requirements.push({
+        builds: builds as any,
+        args: args as any,
+        requires: new Set(requires),
+        init: initOrOpts as any,
+      });
+    } else {
+      const { requires } = initOrOpts ?? {};
+
+      this.#requirements.push({
+        builds: builds as any,
+        args: args as any,
+        requires: new Set(requires),
+      });
+    }
+
+    return this;
+  }
+
+  buildAll(): void {
+    while (this.#requirements.length > 0) {
+      const nextSatisfiedIndex = this.#requirements.findIndex(creation => creation.requires.size === 0);
+
+      if (nextSatisfiedIndex < 0) {
+        throw new Error("Circular dependency for Singleton creation");
+      }
+
+      const [{ builds, args, init }] = this.#requirements.splice(nextSatisfiedIndex, 1);
+
+      if (builds.createInstance !== Singleton.createInstance) {
+        throw new TypeError("Builds is not T extends Singleton");
+      }
+
+      if (args) {
+        const resolvedArgs = typeof args === "function"
+          ? args()
+          : args;
+
+        builds.createInstance(...resolvedArgs);
+      } else {
+        builds.createInstance();
+      }
+
+      init?.(builds.getInstance());
+
+      for (const requirement of this.#requirements) {
+        requirement.requires.delete(builds);
+      }
+    }
+
+    this.#requirements.length = 0;
+  }
+}

src/extensions/extension-discovery.ts

@@ -128,15 +128,15 @@ export class ExtensionDiscovery extends Singleton {
   /**
    * Initializes the class and setups the file watcher for added/removed local extensions.
    */
-  async init(): Promise<void> {
+  init(): void {
     if (ipcRenderer) {
-      await this.initRenderer();
+      this.initRenderer();
     } else {
-      await this.initMain();
+      this.initMain();
     }
   }
 
-  async initRenderer(): Promise<void> {
+  initRenderer(): void {
     const onMessage = ({ isLoaded }: ExtensionDiscoveryChannelMessage) => {
       this.isLoaded = isLoaded;
     };
@@ -147,7 +147,7 @@ export class ExtensionDiscovery extends Singleton {
     });
   }
 
-  async initMain(): Promise<void> {
+  initMain(): void {
     ipcMainHandle(ExtensionDiscovery.extensionDiscoveryChannel, () => this.toJSON());
 
     reaction(() => this.toJSON(), () => {

src/extensions/extension-loader.ts

@@ -72,10 +72,6 @@ export class ExtensionLoader extends Singleton {
 
   @observable isLoaded = false;
 
-  get whenLoaded() {
-    return when(() => this.isLoaded);
-  }
-
   constructor() {
     super();
     makeObservable(this);
@@ -138,23 +134,23 @@ export class ExtensionLoader extends Singleton {
   }
 
   @action
-  async init() {
+  init() {
     if (ipcRenderer) {
-      await this.initRenderer();
+      this.initRenderer();
     } else {
-      await this.initMain();
+      this.initMain();
     }
 
-    await Promise.all([this.whenLoaded]);
+    when(() => this.isLoaded, () => {
+      // broadcasting extensions between main/renderer processes
+      reaction(() => this.toJSON(), () => this.broadcastExtensions(), {
+        fireImmediately: true,
+      });
 
-    // broadcasting extensions between main/renderer processes
-    reaction(() => this.toJSON(), () => this.broadcastExtensions(), {
-      fireImmediately: true,
-    });
-
-    // save state on change `extension.isEnabled`
-    reaction(() => this.storeState, extensionsState => {
-      ExtensionsStore.getInstance().mergeState(extensionsState);
+      // save state on change `extension.isEnabled`
+      reaction(() => this.storeState, extensionsState => {
+        ExtensionsStore.getInstance().mergeState(extensionsState);
+      });
     });
   }
 
@@ -197,7 +193,7 @@ export class ExtensionLoader extends Singleton {
     this.extensions.get(lensExtensionId).isEnabled = isEnabled;
   }
 
-  protected async initMain() {
+  protected initMain() {
     this.isLoaded = true;
     this.loadOnMain();
 
@@ -210,7 +206,7 @@ export class ExtensionLoader extends Singleton {
     });
   }
 
-  protected async initRenderer() {
+  protected initRenderer() {
     const extensionListHandler = (extensions: [LensExtensionId, InstalledExtension][]) => {
       this.isLoaded = true;
       this.syncExtensions(extensions);

src/main/catalog-sources/weblinks.ts

@@ -20,7 +20,7 @@
  */
 
 import { computed, observable, reaction } from "mobx";
-import { WeblinkStore } from "../../common/weblink-store";
+import type { WeblinkStore } from "../../common/weblink-store";
 import { WebLink } from "../../common/catalog-entities";
 import { catalogEntityRegistry } from "../catalog";
 import got from "got";
@@ -45,8 +45,7 @@ async function validateLink(link: WebLink) {
 }
 
 
-export function syncWeblinks() {
-  const weblinkStore = WeblinkStore.getInstance();
+export function syncWeblinks(weblinkStore: WeblinkStore) {
   const webLinkEntities = observable.map<string, [WebLink, Disposer]>();
 
   function periodicallyCheckLink(link: WebLink): Disposer {

src/main/index.ts

@@ -41,7 +41,7 @@ import { InstalledExtension, ExtensionDiscovery } from "../extensions/extension-
 import type { LensExtensionId } from "../extensions/lens-extension";
 import { installDeveloperTools } from "./developer-tools";
 import { LensProtocolRouterMain } from "./protocol-handler";
-import { disposer, getAppVersion, getAppVersionFromProxyServer, storedKubeConfigFolder } from "../common/utils";
+import { CreateSingletons, disposer, getAppVersion, getAppVersionFromProxyServer, storedKubeConfigFolder } from "../common/utils";
 import { bindBroadcastHandlers, ipcMainOn } from "../common/ipc";
 import { startUpdateChecking } from "./app-updater";
 import { IpcRendererNavigationEvents } from "../renderer/navigation/events";
@@ -66,6 +66,7 @@ import { initTray } from "./tray";
 import { kubeApiRequest, shellApiRequest, ShellRequestAuthenticator } from "./proxy-functions";
 import { AppPaths } from "../common/app-paths";
 import { ShellSession } from "./shell-session/shell-session";
+import { DetectorRegistry } from "./cluster-detectors/detector-registry";
 
 injectSystemCAs();
 
@@ -144,10 +145,6 @@ app.on("ready", async () => {
 
   registerFileProtocol("static", __static);
 
-  PrometheusProviderRegistry.createInstance();
-  ShellRequestAuthenticator.createInstance().init();
-  initializers.initPrometheusProviderRegistry();
-
   /**
    * The following sync MUST be done before HotbarStore creation, because that
    * store has migrations that will remove items that previous migrations add
@@ -157,32 +154,38 @@ app.on("ready", async () => {
 
   logger.info("💾 Loading stores");
 
-  UserStore.createInstance().startMainReactions();
+  CreateSingletons.begin()
+    .declare(ClusterManager, manager => manager.init(), {
+      requires: [ClusterStore],
+    })
+    .declare(KubeconfigSyncManager)
+    .declare(ShellRequestAuthenticator, auth => auth.init())
+    .declareWithArgs(LensProxy, [
+      new Router(),
+      {
+        getClusterForRequest: req => ClusterManager.getInstance().getClusterForRequest(req),
+        kubeApiRequest,
+        shellApiRequest,
+      },
+    ])
+    .declare(ClusterStore, store => store.provideInitialFromMain(), {
+      requires: [UserStore],
+    })
+    .declare(HotbarStore, {
+      requires: [ClusterStore],
+    })
+    .declare(PrometheusProviderRegistry, initializers.initPrometheusProviderRegistry)
+    .declare(UserStore, store => store.startMainReactions())
+    .declare(ExtensionsStore)
+    .declare(DetectorRegistry, initializers.initClusterMetadataDetectors)
+    .declare(FilesystemProvisionerStore)
+    .declare(WeblinkStore, syncWeblinks)
+    .declare(HelmRepoManager)
+    .declare(ExtensionDiscovery)
+    .declare(ExtensionLoader)
+    .buildAll();
 
-  // ClusterStore depends on: UserStore
-  ClusterStore.createInstance().provideInitialFromMain();
-
-  // HotbarStore depends on: ClusterStore
-  HotbarStore.createInstance();
-
-  ExtensionsStore.createInstance();
-  FilesystemProvisionerStore.createInstance();
-  WeblinkStore.createInstance();
-
-  syncWeblinks();
-
-  HelmRepoManager.createInstance(); // create the instance
-
-  const lensProxy = LensProxy.createInstance(new Router(), {
-    getClusterForRequest: req => ClusterManager.getInstance().getClusterForRequest(req),
-    kubeApiRequest,
-    shellApiRequest,
-  });
-
-  ClusterManager.createInstance().init();
-  KubeconfigSyncManager.createInstance();
-
-  initializers.initClusterMetadataDetectors();
+  const lensProxy = LensProxy.getInstance();
 
   try {
     logger.info("🔌 Starting LensProxy");
@@ -224,9 +227,10 @@ app.on("ready", async () => {
   }
 
   initializers.initRegistries();
-  const extensionDiscovery = ExtensionDiscovery.createInstance();
+  ExtensionLoader.getInstance().init();
+
+  const extensionDiscovery = ExtensionDiscovery.getInstance();
 
-  ExtensionLoader.createInstance().init();
   extensionDiscovery.init();
 
   // Start the app without showing the main window when auto starting on login

src/main/initializers/cluster-metadata-detectors.ts

@@ -20,14 +20,14 @@
  */
 
 import { ClusterIdDetector } from "../cluster-detectors/cluster-id-detector";
-import { DetectorRegistry } from "../cluster-detectors/detector-registry";
+import type { DetectorRegistry } from "../cluster-detectors/detector-registry";
 import { DistributionDetector } from "../cluster-detectors/distribution-detector";
 import { LastSeenDetector } from "../cluster-detectors/last-seen-detector";
 import { NodesCountDetector } from "../cluster-detectors/nodes-count-detector";
 import { VersionDetector } from "../cluster-detectors/version-detector";
 
-export function initClusterMetadataDetectors() {
-  DetectorRegistry.createInstance()
+export function initClusterMetadataDetectors(registry: DetectorRegistry) {
+  registry
     .add(ClusterIdDetector)
     .add(LastSeenDetector)
     .add(VersionDetector)

src/main/initializers/metrics-providers.ts

@@ -19,15 +19,14 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-import { PrometheusProviderRegistry } from "../prometheus";
+import type { PrometheusProviderRegistry } from "../prometheus";
 import { PrometheusHelm } from "../prometheus/helm";
 import { PrometheusLens } from "../prometheus/lens";
 import { PrometheusOperator } from "../prometheus/operator";
 import { PrometheusStacklight } from "../prometheus/stacklight";
 
-export function initPrometheusProviderRegistry() {
-  PrometheusProviderRegistry
-    .getInstance()
+export function initPrometheusProviderRegistry(registry: PrometheusProviderRegistry) {
+  registry
     .registerProvider(new PrometheusLens())
     .registerProvider(new PrometheusHelm())
     .registerProvider(new PrometheusOperator())

src/renderer/bootstrap.tsx

@@ -29,17 +29,16 @@ import * as ReactRouterDom from "react-router-dom";
 import * as LensExtensionsCommonApi from "../extensions/common-api";
 import * as LensExtensionsRendererApi from "../extensions/renderer-api";
 import { render } from "react-dom";
-import { delay } from "../common/utils";
+import { CreateSingletons, delay } from "../common/utils";
 import { isMac, isDevelopment } from "../common/vars";
 import { ClusterStore } from "../common/cluster-store";
 import { UserStore } from "../common/user-store";
 import { ExtensionDiscovery } from "../extensions/extension-discovery";
 import { ExtensionLoader } from "../extensions/extension-loader";
 import { HelmRepoManager } from "../main/helm/helm-repo-manager";
-import { ExtensionInstallationStateStore } from "./components/+extensions/extension-install.store";
 import { DefaultProps } from "./mui-base-theme";
 import configurePackages from "../common/configure-packages";
-import * as initializers from "./initializers";
+import { initializers } from "./initializers";
 import logger from "../common/logger";
 import { HotbarStore } from "../common/hotbar-store";
 import { WeblinkStore } from "../common/weblink-store";
@@ -53,6 +52,7 @@ import { registerCustomThemes } from "./components/monaco-editor";
 import { getDi } from "./components/getDi";
 import { DiContextProvider } from "@ogre-tools/injectable-react";
 import type { DependencyInjectionContainer } from "@ogre-tools/injectable";
+import { ExtensionInstallationStateStore } from "./components/+extensions/extension-install.store";
 
 if (process.isMainFrame) {
   SentryInit();
@@ -80,73 +80,42 @@ export async function bootstrap(comp: () => Promise<AppComponent>, di: Dependenc
   const rootElem = document.getElementById("app");
   const logPrefix = `[BOOTSTRAP-${process.isMainFrame ? "ROOT" : "CLUSTER"}-FRAME]:`;
 
-  await AppPaths.init();
-  UserStore.createInstance();
-
   await attachChromeDebugger();
   rootElem.classList.toggle("is-mac", isMac);
 
-  logger.info(`${logPrefix} initializing Registries`);
-  initializers.initRegistries();
+  for (const [name, init] of initializers) {
+    logger.info(`${logPrefix} initializing ${name}`);
+    init();
+  }
 
-  logger.info(`${logPrefix} initializing CommandRegistry`);
-  initializers.initCommandRegistry();
-
-  logger.info(`${logPrefix} initializing EntitySettingsRegistry`);
-  initializers.initEntitySettingsRegistry();
-
-  logger.info(`${logPrefix} initializing KubeObjectMenuRegistry`);
-  initializers.initKubeObjectMenuRegistry();
-
-  logger.info(`${logPrefix} initializing KubeObjectDetailRegistry`);
-  initializers.initKubeObjectDetailRegistry();
-
-  logger.info(`${logPrefix} initializing WelcomeMenuRegistry`);
-  initializers.initWelcomeMenuRegistry();
-
-  logger.info(`${logPrefix} initializing WorkloadsOverviewDetailRegistry`);
-  initializers.initWorkloadsOverviewDetailRegistry();
-
-  logger.info(`${logPrefix} initializing CatalogEntityDetailRegistry`);
-  initializers.initCatalogEntityDetailRegistry();
-
-  logger.info(`${logPrefix} initializing CatalogCategoryRegistryEntries`);
-  initializers.initCatalogCategoryRegistryEntries();
-
-  logger.info(`${logPrefix} initializing Catalog`);
-  initializers.initCatalog();
-
-  logger.info(`${logPrefix} initializing IpcRendererListeners`);
-  initializers.initIpcRendererListeners();
-
-  logger.info(`${logPrefix} initializing StatusBarRegistry`);
-  initializers.initStatusBarRegistry();
-
-  ExtensionLoader.createInstance().init();
-  ExtensionDiscovery.createInstance().init();
-
-  // ClusterStore depends on: UserStore
-  const clusterStore = ClusterStore.createInstance();
-
-  await clusterStore.loadInitialOnRenderer();
-
-  // HotbarStore depends on: ClusterStore
-  HotbarStore.createInstance();
-  ExtensionsStore.createInstance();
-  FilesystemProvisionerStore.createInstance();
-
-  // ThemeStore depends on: UserStore
-  ThemeStore.createInstance();
-
-  // TerminalStore depends on: ThemeStore
-  TerminalStore.createInstance();
-  WeblinkStore.createInstance();
+  await AppPaths.init();
+  CreateSingletons.begin()
+    .declare(ExtensionDiscovery, discovery => discovery.init())
+    .declare(ExtensionLoader, loader => loader.init())
+    .declare(UserStore)
+    .declare(ExtensionsStore)
+    .declare(FilesystemProvisionerStore)
+    .declare(WeblinkStore)
+    .declare(HelmRepoManager)
+    .declare(ClusterStore, async store => {
+      await store.loadInitialOnRenderer();
+      store.registerIpcListener();
+    },
+    {
+      requires: [UserStore],
+    })
+    .declare(HotbarStore, {
+      requires: [ClusterStore],
+    })
+    .declare(ThemeStore, {
+      requires: [UserStore],
+    })
+    .declare(TerminalStore, {
+      requires: [ThemeStore],
+    })
+    .buildAll();
 
   ExtensionInstallationStateStore.bindIpcListeners();
-  HelmRepoManager.createInstance(); // initialize the manager
-
-  // Register additional store listeners
-  clusterStore.registerIpcListener();
 
   // init app's dependencies if any
   const App = await comp();

src/renderer/initializers/index.ts

@@ -19,15 +19,30 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-export * from "./catalog-entity-detail-registry";
-export * from "./catalog";
-export * from "./command-registry";
-export * from "./entity-settings-registry";
-export * from "./ipc";
-export * from "./kube-object-detail-registry";
-export * from "./kube-object-menu-registry";
-export * from "./registries";
-export * from "./welcome-menu-registry";
-export * from "./workloads-overview-detail-registry";
-export * from "./catalog-category-registry";
-export * from "./status-bar-registry";
+import { initCatalogEntityDetailRegistry } from "./catalog-entity-detail-registry";
+import { initCatalog } from "./catalog";
+import { initCommandRegistry } from "./command-registry";
+import { initEntitySettingsRegistry } from "./entity-settings-registry";
+import { initIpcRendererListeners } from "./ipc";
+import { initKubeObjectDetailRegistry } from "./kube-object-detail-registry";
+import { initKubeObjectMenuRegistry } from "./kube-object-menu-registry";
+import { initRegistries } from "./registries";
+import { initWelcomeMenuRegistry } from "./welcome-menu-registry";
+import { initWorkloadsOverviewDetailRegistry } from "./workloads-overview-detail-registry";
+import { initCatalogCategoryRegistryEntries } from "./catalog-category-registry";
+import { initStatusBarRegistry } from "./status-bar-registry";
+
+export const initializers: [string, () => void][] = [
+  ["Registries", initRegistries], // This line must be must be first
+  ["CommandRegistry", initCommandRegistry],
+  ["EntitySettingsRegistry", initEntitySettingsRegistry],
+  ["KubeObjectMenuRegistry", initKubeObjectMenuRegistry],
+  ["KubeObjectDetailRegistry", initKubeObjectDetailRegistry],
+  ["WelcomeMenuRegistry", initWelcomeMenuRegistry],
+  ["WorkloadsOverviewDetailRegistry", initWorkloadsOverviewDetailRegistry],
+  ["CatalogEntityDetailRegistry", initCatalogEntityDetailRegistry],
+  ["CatalogCategoryRegistryEntries", initCatalogCategoryRegistryEntries],
+  ["Catalog", initCatalog],
+  ["IpcRendererListeners", initIpcRendererListeners],
+  ["StatusBarRegistry", initStatusBarRegistry],
+];