TechDocs: Refactor metadata retrieval

1. Don't use mkdocs in name of APIs or variables. It is an implementation detail and liable to change in future.
2. techDocsApi.getMetadata('mkdocs') and techDocsAPI.getMetadata('entity') should be two separate functions just because their responses differ in structure. They should also be type checked.
3. Use either 'techdocs' or 'TechDocs' consistently. 'techDocs' seems like an unnecessary third way to write TechDocs, which can be avoided.
4. Remove unused /plugins/techdocs-backend/src/service/metadata.ts file

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

@@ -1,41 +0,0 @@
-/*
- * Copyright 2020 Spotify AB
- *
- * 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 fetch from 'cross-fetch';
-
-export class TechDocsMetadata {
-  private async getMetadataFile(docsUrl: String) {
-    const metadataURL = `${docsUrl}/techdocs_metadata.json`;
-
-    try {
-      const req = await fetch(metadataURL);
-
-      return await req.json();
-    } catch (error) {
-      throw new Error(error);
-    }
-  }
-
-  public async getMkDocsMetaData(docsUrl: any) {
-    const mkDocsMetadata = await this.getMetadataFile(docsUrl);
-
-    if (!mkDocsMetadata) return null;
-
-    return {
-      ...mkDocsMetadata,
-    };
-  }
-}

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

@@ -61,7 +61,7 @@ export async function createRouter({
 }: RouterOptions): Promise<express.Router> {
   const router = Router();
 
-  router.get('/metadata/mkdocs/*', async (req, res) => {
+  router.get('/metadata/techdocs/*', async (req, res) => {
     let storageUrl = config.getString('techdocs.storageUrl');
     if (publisher instanceof LocalPublish) {
       storageUrl = new URL(
@@ -74,8 +74,8 @@ export async function createRouter({
     const metadataURL = `${storageUrl}/${path}/techdocs_metadata.json`;
 
     try {
-      const mkDocsMetadata = await (await fetch(metadataURL)).json();
-      res.send(mkDocsMetadata);
+      const techdocsMetadata = await (await fetch(metadataURL)).json();
+      res.send(techdocsMetadata);
     } catch (err) {
       logger.info(`Unable to get metadata for ${path} with error ${err}`);
       throw new Error(`Unable to get metadata for ${path} with error ${err}`);