feat(tech-insights): support registry and persistence at plugin

Support `FactRetrieverRegistry` and `PersistenceContext` at the `techInsightsPlugin`
using extension points.

Additionally, move `FactRetrieverRegistry` and `PersistenceContext`
to `@backstage/plugin-tech-insights-node`.
Original exports are marked as deprecated and re-export the moved types.

Signed-off-by: Patrick Jungermann <Patrick.Jungermann@gmail.com>

plugins/tech-insights-node/src/extensionPoints.ts

@@ -16,8 +16,9 @@
 
 import { createExtensionPoint } from '@backstage/backend-plugin-api';
 import { CheckResult } from '@backstage/plugin-tech-insights-common';
-import { FactRetriever } from './facts';
 import { FactCheckerFactory, TechInsightCheck } from './checks';
+import { FactRetriever, FactRetrieverRegistry } from './facts';
+import { PersistenceContext } from './persistence';
 
 /**
  * @public
@@ -57,3 +58,37 @@ export const techInsightsFactCheckerFactoryExtensionPoint =
   createExtensionPoint<TechInsightsFactCheckerFactoryExtensionPoint>({
     id: 'tech-insights.fact-checker-factory',
   });
+
+/**
+ * @public
+ */
+export interface TechInsightsFactRetrieverRegistryExtensionPoint {
+  setFactRetrieverRegistry(registry: FactRetrieverRegistry): void;
+}
+
+/**
+ * An extension point that allows other plugins or modules to set a custom FactRetrieverRegistry.
+ *
+ * @public
+ */
+export const techInsightsFactRetrieverRegistryExtensionPoint =
+  createExtensionPoint<TechInsightsFactRetrieverRegistryExtensionPoint>({
+    id: 'tech-insights.fact-retriever-registry',
+  });
+
+/**
+ * @public
+ */
+export interface TechInsightsPersistenceContextExtensionPoint {
+  setPersistenceContext(context: PersistenceContext): void;
+}
+
+/**
+ * An extension point that allows other plugins or modules to set a custom PersistenceContext.
+ *
+ * @public
+ */
+export const techInsightsPersistenceContextExtensionPoint =
+  createExtensionPoint<TechInsightsPersistenceContextExtensionPoint>({
+    id: 'tech-insights.persistence-context',
+  });

plugins/tech-insights-node/src/facts.ts

@@ -230,3 +230,14 @@ export type FactRetrieverRegistration = {
    */
   initialDelay?: Duration | HumanDuration;
 };
+
+/**
+ * @public
+ */
+export interface FactRetrieverRegistry {
+  register(registration: FactRetrieverRegistration): Promise<void>;
+  get(retrieverReference: string): Promise<FactRetrieverRegistration>;
+  listRetrievers(): Promise<FactRetriever[]>;
+  listRegistrations(): Promise<FactRetrieverRegistration[]>;
+  getSchemas(): Promise<FactSchema[]>;
+}

plugins/tech-insights-node/src/persistence.ts

@@ -22,6 +22,15 @@ import {
 import { DateTime } from 'luxon';
 import { FactSchema } from '@backstage/plugin-tech-insights-common';
 
+/**
+ * A Container for persistence related components in TechInsights
+ *
+ * @public
+ */
+export type PersistenceContext = {
+  techInsightsStore: TechInsightsStore;
+};
+
 /**
  * TechInsights Database
  *