Merge pull request #24796 from brianphillips/search-backend-build-ordering

Split search backend plugin initialization into init and start phases

.changeset/seven-geese-raise.md

@@ -0,0 +1,6 @@
+---
+'@backstage/plugin-search-backend-node': patch
+'@backstage/plugin-search-backend': patch
+---
+
+Split backend search plugin startup into "init" and "start" stages to ensure necessary initialization has happened before startup

plugins/search-backend-node/api-report-alpha.md

@@ -33,19 +33,20 @@ export const searchIndexRegistryExtensionPoint: ExtensionPoint<SearchIndexRegist
 // @alpha
 export interface SearchIndexService {
   getDocumentTypes(): Record<string, DocumentTypeInfo>;
-  start(options: SearchIndexServiceStartOptions): Promise<void>;
+  init(options: SearchIndexServiceInitOptions): void;
+  start(): Promise<void>;
   stop(): Promise<void>;
 }
 
 // @alpha
-export const searchIndexServiceRef: ServiceRef<SearchIndexService, 'plugin'>;
-
-// @alpha
-export type SearchIndexServiceStartOptions = {
+export type SearchIndexServiceInitOptions = {
   searchEngine: SearchEngine;
   collators: RegisterCollatorParameters[];
   decorators: RegisterDecoratorParameters[];
 };
 
+// @alpha
+export const searchIndexServiceRef: ServiceRef<SearchIndexService, 'plugin'>;
+
 // (No @packageDocumentation comment for this package)
 ```

plugins/search-backend-node/src/alpha.ts

@@ -32,9 +32,9 @@ import {
 
 /**
  * @alpha
- * Options for build method on {@link SearchIndexService}.
+ * Options for the init method on {@link SearchIndexService}.
  */
-export type SearchIndexServiceStartOptions = {
+export type SearchIndexServiceInitOptions = {
   searchEngine: SearchEngine;
   collators: RegisterCollatorParameters[];
   decorators: RegisterDecoratorParameters[];
@@ -45,15 +45,21 @@ export type SearchIndexServiceStartOptions = {
  * Interface for implementation of index service.
  */
 export interface SearchIndexService {
+  /**
+   * Initializes state in preparation for starting the search index service
+   */
+  init(options: SearchIndexServiceInitOptions): void;
+
   /**
    * Starts indexing process
    */
-  start(options: SearchIndexServiceStartOptions): Promise<void>;
+  start(): Promise<void>;
 
   /**
    * Stops indexing process
    */
   stop(): Promise<void>;
+
   /**
    * Returns an index types list.
    */
@@ -83,7 +89,7 @@ type DefaultSearchIndexServiceOptions = {
 
 /**
  * @alpha
- * Reponsible for register the indexing task and start the schedule.
+ * Responsible for register the indexing task and start the schedule.
  */
 class DefaultSearchIndexService implements SearchIndexService {
   private readonly logger: LoggerService;
@@ -98,7 +104,7 @@ class DefaultSearchIndexService implements SearchIndexService {
     return new DefaultSearchIndexService(options);
   }
 
-  async start(options: SearchIndexServiceStartOptions): Promise<void> {
+  init(options: SearchIndexServiceInitOptions): void {
     this.indexBuilder = new IndexBuilder({
       logger: this.logger,
       searchEngine: options.searchEngine,
@@ -111,8 +117,13 @@ class DefaultSearchIndexService implements SearchIndexService {
     options.decorators.forEach(decorator =>
       this.indexBuilder?.addDecorator(decorator),
     );
+  }
 
-    const { scheduler } = await this.indexBuilder?.build();
+  async start(): Promise<void> {
+    if (!this.indexBuilder) {
+      throw new Error('IndexBuilder is not initialized, call init first');
+    }
+    const { scheduler } = await this.indexBuilder.build();
     this.scheduler = scheduler;
     this.scheduler!.start();
   }

plugins/search-backend/src/alpha.ts

@@ -121,13 +121,14 @@ export default createBackendPlugin({
 
         const collators = searchIndexRegistry.getCollators();
         const decorators = searchIndexRegistry.getDecorators();
+        searchIndexService.init({
+          searchEngine: searchEngine!,
+          collators,
+          decorators,
+        });
 
         lifecycle.addStartupHook(async () => {
-          await searchIndexService.start({
-            searchEngine: searchEngine!,
-            collators,
-            decorators,
-          });
+          await searchIndexService.start();
         });
 
         lifecycle.addShutdownHook(async () => {