Make type(s) readonly properties of Collator/Decorator classes

Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

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

@@ -24,22 +24,33 @@ import { IndexBuilder } from './IndexBuilder';
 import { LunrSearchEngine, SearchEngine } from './index';
 
 class TestDocumentCollator implements DocumentCollator {
-  async execute() {
+  readonly type: string = 'anything';
+  async execute(): Promise<IndexableDocument[]> {
     return [];
   }
 }
 
+class TypedDocumentCollator extends TestDocumentCollator {
+  readonly type = 'an-expected-type';
+}
+
 class TestDocumentDecorator implements DocumentDecorator {
-  async execute(_type: string, documents: IndexableDocument[]) {
+  async execute(documents: IndexableDocument[]) {
     return documents;
   }
 }
 
+class TypedDocumentDecorator extends TestDocumentDecorator {
+  readonly types = ['an-expected-type'];
+}
+
+class DifferentlyTypedDocumentDecorator extends TestDocumentDecorator {
+  readonly types = ['not-the-expected-type'];
+}
+
 describe('IndexBuilder', () => {
   let testSearchEngine: SearchEngine;
   let testIndexBuilder: IndexBuilder;
-  let testCollator: DocumentCollator;
-  let testDecorator: DocumentDecorator;
 
   beforeEach(() => {
     const logger = getVoidLogger();
@@ -48,18 +59,16 @@ describe('IndexBuilder', () => {
       logger,
       searchEngine: testSearchEngine,
     });
-    testCollator = new TestDocumentCollator();
-    testDecorator = new TestDocumentDecorator();
   });
 
   describe('addCollator', () => {
     it('adds a collator', async () => {
       jest.useFakeTimers();
+      const testCollator = new TestDocumentCollator();
       const collatorSpy = jest.spyOn(testCollator, 'execute');
 
       // Add a collator.
       testIndexBuilder.addCollator({
-        type: 'anything',
         defaultRefreshIntervalSeconds: 6,
         collator: testCollator,
       });
@@ -75,11 +84,12 @@ describe('IndexBuilder', () => {
   describe('addDecorator', () => {
     it('adds a decorator', async () => {
       jest.useFakeTimers();
+      const testCollator = new TestDocumentCollator();
+      const testDecorator = new TestDocumentDecorator();
       const decoratorSpy = jest.spyOn(testDecorator, 'execute');
 
       // Add a collator.
       testIndexBuilder.addCollator({
-        type: 'anything',
         defaultRefreshIntervalSeconds: 6,
         collator: testCollator,
       });
@@ -100,7 +110,8 @@ describe('IndexBuilder', () => {
 
     it('adds a type-specific decorator', async () => {
       jest.useFakeTimers();
-      const expectedType = 'an-expected-type';
+      const testCollator = new TypedDocumentCollator();
+      const testDecorator = new TypedDocumentDecorator();
       const docFixture = {
         title: 'Test',
         text: 'Test text.',
@@ -113,14 +124,12 @@ describe('IndexBuilder', () => {
 
       // Add a collator.
       testIndexBuilder.addCollator({
-        type: expectedType,
         defaultRefreshIntervalSeconds: 6,
         collator: testCollator,
       });
 
       // Add a decorator for the same type.
       testIndexBuilder.addDecorator({
-        types: [expectedType],
         decorator: testDecorator,
       });
 
@@ -131,16 +140,17 @@ describe('IndexBuilder', () => {
       // wait for async decorator execution
       await Promise.resolve();
       expect(decoratorSpy).toHaveBeenCalled();
-      expect(decoratorSpy).toHaveBeenCalledWith(expectedType, [docFixture]);
+      expect(decoratorSpy).toHaveBeenCalledWith([docFixture]);
     });
 
     it('adds a type-specific decorator that should not be called', async () => {
-      const expectedType = 'an-expected-type';
       const docFixture = {
         title: 'Test',
         text: 'Test text.',
         location: '/test/location',
       };
+      const testCollator = new TestDocumentCollator();
+      const testDecorator = new DifferentlyTypedDocumentDecorator();
       const collatorSpy = jest
         .spyOn(testCollator, 'execute')
         .mockImplementation(async () => [docFixture]);
@@ -148,14 +158,12 @@ describe('IndexBuilder', () => {
 
       // Add a collator.
       testIndexBuilder.addCollator({
-        type: expectedType,
         defaultRefreshIntervalSeconds: 6,
         collator: testCollator,
       });
 
       // Add a decorator for a different type.
       testIndexBuilder.addDecorator({
-        types: ['not-the-expected-type'],
         decorator: testDecorator,
       });
 

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

@@ -55,28 +55,25 @@ export class IndexBuilder {
    * given refresh interval.
    */
   addCollator({
-    type,
     collator,
     defaultRefreshIntervalSeconds,
   }: RegisterCollatorParameters): void {
     this.logger.info(
-      `Added ${collator.constructor.name} collator for type ${type}`,
+      `Added ${collator.constructor.name} collator for type ${collator.type}`,
     );
-    this.collators[type] = {
+    this.collators[collator.type] = {
       refreshInterval: defaultRefreshIntervalSeconds,
       collate: collator,
     };
   }
 
   /**
-   * Makes the index builder aware of a decorator. If no types are provided, it
-   * will be applied to documents from all known collators, otherwise it will
-   * only be applied to documents of the given types.
+   * Makes the index builder aware of a decorator. If no types are provided on
+   * the decorator, it will be applied to documents from all known collators,
+   * otherwise it will only be applied to documents of the given types.
    */
-  addDecorator({
-    types = ['*'],
-    decorator,
-  }: RegisterDecoratorParameters): void {
+  addDecorator({ decorator }: RegisterDecoratorParameters): void {
+    const types = decorator.types || ['*'];
     this.logger.info(
       `Added decorator ${decorator.constructor.name} to types ${types.join(
         ', ',
@@ -113,7 +110,7 @@ export class IndexBuilder {
           this.logger.debug(
             `Decorating ${type} documents via ${decorators[i].constructor.name}`,
           );
-          documents = await decorators[i].execute(type, documents);
+          documents = await decorators[i].execute(documents);
         }
 
         if (!documents || documents.length === 0) {

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

@@ -26,11 +26,6 @@ import {
  * Parameters required to register a collator.
  */
 export interface RegisterCollatorParameters {
-  /**
-   * The type of document to be indexed (used to name indices, to configure refresh loop, etc).
-   */
-  type: string;
-
   /**
    * The default interval (in seconds) that the provided collator will be called (can be overridden in config).
    */
@@ -50,12 +45,6 @@ export interface RegisterDecoratorParameters {
    * The decorator class responsible for appending or modifying documents of the given type(s).
    */
   decorator: DocumentDecorator;
-
-  /**
-   * (Optional) An array of document types that the given decorator should apply to. If none are provided,
-   * the decorator will be applied to all types.
-   */
-  types?: string[];
 }
 
 /**