feat(search): create search services and extension points

Signed-off-by: Camila Belo <camilaibs@gmail.com>

plugins/search-backend-node/package.json

@@ -24,6 +24,7 @@
   },
   "dependencies": {
     "@backstage/backend-common": "workspace:^",
+    "@backstage/backend-plugin-api": "workspace:^",
     "@backstage/backend-tasks": "workspace:^",
     "@backstage/config": "workspace:^",
     "@backstage/errors": "workspace:^",

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

@@ -14,7 +14,6 @@
  * limitations under the License.
  */
 
-import { createServiceRef } from '@backstage/backend-plugin-api';
 import {
   DocumentDecoratorFactory,
   DocumentTypeInfo,
@@ -24,20 +23,16 @@ import { Transform, pipeline } from 'stream';
 import { Logger } from 'winston';
 import { Scheduler } from './Scheduler';
 import {
-  IndexBuilderService,
   IndexBuilderOptions,
   RegisterCollatorParameters,
   RegisterDecoratorParameters,
 } from './types';
 
-export const searchIndexBuilderRef = createServiceRef<IndexBuilderService>({
-  id: 'search.index-node',
-});
 /**
  * Used for adding collators, decorators and compile them into tasks which are added to a scheduler returned to the caller.
  * @public
  */
-export class IndexBuilder implements IndexBuilderService {
+export class IndexBuilder {
   private collators: Record<string, RegisterCollatorParameters>;
   private decorators: Record<string, DocumentDecoratorFactory[]>;
   private documentTypes: Record<string, DocumentTypeInfo>;

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

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2023 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { createExtensionPoint } from '@backstage/backend-plugin-api';
+import {
+  SearchEngineRegistryExtensionPoint,
+  SearchIndexRegistryExtensionPoint,
+} from './types';
+
+export const searchEngineRegistryExtensionPoint =
+  createExtensionPoint<SearchEngineRegistryExtensionPoint>({
+    id: 'search.engine.registry',
+  });
+
+export const searchIndexRegistryExtensionPoint =
+  createExtensionPoint<SearchIndexRegistryExtensionPoint>({
+    id: 'search.index.registry',
+  });

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

@@ -20,7 +20,7 @@
  * @packageDocumentation
  */
 
-export { IndexBuilder, searchIndexBuilderRef } from './IndexBuilder';
+export { IndexBuilder } from './IndexBuilder';
 export { Scheduler } from './Scheduler';
 export * from './collators';
 export { LunrSearchEngine } from './engines';
@@ -33,9 +33,15 @@ export type {
   IndexBuilderOptions,
   RegisterCollatorParameters,
   RegisterDecoratorParameters,
+  SearchIndexRegistryExtensionPoint,
+  SearchEngineRegistryExtensionPoint,
 } from './types';
 export * from './errors';
 export * from './indexing';
 export * from './test-utils';
 
 export type { ScheduleTaskParameters } from './Scheduler';
+
+// TODO: export as alfa subpath
+export * from './services';
+export * from './extensions';

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

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2023 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Logger } from 'winston';
+import {
+  createServiceRef,
+  createServiceFactory,
+  coreServices,
+} from '@backstage/backend-plugin-api';
+import { DocumentTypeInfo } from '@backstage/plugin-search-common';
+import { IndexBuilder } from './IndexBuilder';
+import { Scheduler } from './Scheduler';
+import {
+  IndexBuilderServiceBuildOptions,
+  SearchIndexBuilderService,
+} from './types';
+import { loggerToWinstonLogger } from '@backstage/backend-common';
+
+type DefaultSearchIndexBuilderServiceOptions = {
+  logger: Logger;
+};
+
+class DefaultSearchIndexBuilderService implements SearchIndexBuilderService {
+  private logger: Logger;
+  private indexBuilder: IndexBuilder | null = null;
+
+  private constructor(options: DefaultSearchIndexBuilderServiceOptions) {
+    this.logger = options.logger;
+  }
+
+  static fromConfig(options: DefaultSearchIndexBuilderServiceOptions) {
+    return new DefaultSearchIndexBuilderService(options);
+  }
+
+  build(
+    options: IndexBuilderServiceBuildOptions,
+  ): Promise<{ scheduler: Scheduler }> {
+    this.indexBuilder = new IndexBuilder({
+      logger: this.logger,
+      searchEngine: options.searchEngine,
+    });
+
+    options.collators.forEach(collator =>
+      this.indexBuilder?.addCollator(collator),
+    );
+
+    options.decorators.forEach(decorator =>
+      this.indexBuilder?.addDecorator(decorator),
+    );
+
+    return this.indexBuilder?.build();
+  }
+
+  getDocumentTypes(): Record<string, DocumentTypeInfo> {
+    return this.indexBuilder?.getDocumentTypes() ?? {};
+  }
+}
+
+export const searchIndexBuilderService =
+  createServiceRef<SearchIndexBuilderService>({
+    id: 'search.index.builder',
+    defaultFactory: async service =>
+      createServiceFactory({
+        service,
+        deps: {
+          logger: coreServices.logger,
+        },
+        factory({ logger }) {
+          return DefaultSearchIndexBuilderService.fromConfig({
+            logger: loggerToWinstonLogger(logger),
+          });
+        },
+      }),
+  });

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

@@ -65,7 +65,7 @@ export type IndexBuilderServiceBuildOptions = {
   collators: RegisterCollatorParameters[];
   decorators: RegisterDecoratorParameters[];
 };
-export interface IndexBuilderService {
+export interface SearchIndexBuilderService {
   build(options: IndexBuilderServiceBuildOptions): Promise<{
     scheduler: Scheduler;
   }>;
@@ -81,5 +81,5 @@ export interface SearchIndexRegistryExtensionPoint {
 
 export interface SearchEngineRegistryExtensionPoint {
   setSearchEngine(searchEngine: SearchEngine): void;
-  getSearchEngine(): SearchEngine;
+  getSearchEngine(): SearchEngine | null;
 }