Refactor to a private constructor and static fromConfig

Signed-off-by: Nikolas Skoufis <nskoufis@seek.com.au>

plugins/techdocs-backend/src/service/DocsBuildStrategy.test.ts

@@ -41,7 +41,8 @@ describe('DefaultDocsBuildStrategy', () => {
 
   describe('shouldBuild', () => {
     it('should return true when techdocs.build is set to local', async () => {
-      const defaultDocsBuildStrategy = new DefaultDocsBuildStrategy(config);
+      const defaultDocsBuildStrategy =
+        DefaultDocsBuildStrategy.fromConfig(config);
 
       MockedConfigReader.prototype.getString.mockReturnValue('local');
 
@@ -51,7 +52,8 @@ describe('DefaultDocsBuildStrategy', () => {
     });
 
     it('should return false when techdocs.build is set to external', async () => {
-      const defaultDocsBuildStrategy = new DefaultDocsBuildStrategy(config);
+      const defaultDocsBuildStrategy =
+        DefaultDocsBuildStrategy.fromConfig(config);
 
       MockedConfigReader.prototype.getString.mockReturnValue('external');
 

plugins/techdocs-backend/src/service/DocsBuildStrategy.ts

@@ -28,10 +28,14 @@ export interface DocsBuildStrategy {
 export class DefaultDocsBuildStrategy {
   private readonly config: Config;
 
-  constructor(config: Config) {
+  private constructor(config: Config) {
     this.config = config;
   }
 
+  static fromConfig(config: Config): DefaultDocsBuildStrategy {
+    return new DefaultDocsBuildStrategy(config);
+  }
+
   async shouldBuild(_: Entity): Promise<boolean> {
     return this.config.getString('techdocs.builder') === 'local';
   }

plugins/techdocs-backend/src/service/router.ts

@@ -106,7 +106,7 @@ export async function createRouter(
   const { publisher, config, logger, discovery } = options;
   const catalogClient = new CatalogClient({ discoveryApi: discovery });
   const docsBuildStrategy =
-    options.docsBuildStrategy ?? new DefaultDocsBuildStrategy(config);
+    options.docsBuildStrategy ?? DefaultDocsBuildStrategy.fromConfig(config);
 
   // Entities are cached to optimize the /static/docs request path, which can be called many times
   // when loading a single techdocs page.