chore(example-file-upload): address review comments

examples/file-upload/src/application.ts

@@ -5,7 +5,7 @@
 
 import {BootMixin} from '@loopback/boot';
 import {ApplicationConfig} from '@loopback/core';
-import {RestApplication, RestBindings} from '@loopback/rest';
+import {RestApplication} from '@loopback/rest';
 import {
   RestExplorerBindings,
   RestExplorerComponent,
@@ -32,23 +32,7 @@ export class FileUploadApplication extends BootMixin(RestApplication) {
     this.component(RestExplorerComponent);
 
     // Configure file upload with multer options
-    const multerOptions: multer.Options = {
-      storage: multer.diskStorage({
-        // Upload files to `.sandbox`
-        destination: path.join(__dirname, '../.sandbox'),
-        // Use the original file name as is
-        filename: (req, file, cb) => {
-          cb(null, file.originalname);
-        },
-      }),
-    };
-    this.configure(FILE_UPLOAD_SERVICE).to(multerOptions);
-
-    // Configure AJV to ignore `binary` format which is required for OpenAPI
-    // spec 3.0 for file uploads
-    this.bind(RestBindings.REQUEST_BODY_PARSER_OPTIONS).to({
-      validation: {unknownFormats: ['binary']},
-    });
+    this.configureFileUpload();
 
     this.projectRoot = __dirname;
     // Customize @loopback/boot Booter Conventions here
@@ -61,4 +45,22 @@ export class FileUploadApplication extends BootMixin(RestApplication) {
       },
     };
   }
+
+  /**
+   * Configure `multer` options for file upload
+   */
+  protected configureFileUpload() {
+    const multerOptions: multer.Options = {
+      storage: multer.diskStorage({
+        // Upload files to `.sandbox`
+        destination: path.join(__dirname, '../.sandbox'),
+        // Use the original file name as is
+        filename: (req, file, cb) => {
+          cb(null, file.originalname);
+        },
+      }),
+    };
+    // Configure the file upload service with multer options
+    this.configure(FILE_UPLOAD_SERVICE).to(multerOptions);
+  }
 }

examples/file-upload/src/controllers/file-upload.controller.ts

@@ -11,8 +11,8 @@ import {
   Response,
   RestBindings,
 } from '@loopback/rest';
-import {RequestHandler} from 'express-serve-static-core';
 import {FILE_UPLOAD_SERVICE} from '../keys';
+import {FileUploadHandler} from '../types';
 
 /**
  * A controller to handle file uploads using multipart/form-data media type
@@ -22,7 +22,9 @@ export class FileUploadController {
    * Constructor
    * @param handler - Inject an express request handler to deal with the request
    */
-  constructor(@inject(FILE_UPLOAD_SERVICE) private handler: RequestHandler) {}
+  constructor(
+    @inject(FILE_UPLOAD_SERVICE) private handler: FileUploadHandler,
+  ) {}
   @post('/file-upload', {
     responses: {
       200: {
@@ -33,7 +35,7 @@ export class FileUploadController {
             },
           },
         },
-        description: '',
+        description: 'Files and fields',
       },
     },
   })
@@ -78,6 +80,10 @@ export class FileUploadController {
     });
   }
 
+  /**
+   * Get files and fields for the request
+   * @param request - Http request
+   */
   private static getFilesAndFields(request: Request) {
     const uploadedFiles = request.files;
     const mapper = (f: globalThis.Express.Multer.File) => ({

examples/file-upload/src/keys.ts

@@ -4,8 +4,11 @@
 // License text available at https://opensource.org/licenses/MIT
 
 import {BindingKey} from '@loopback/core';
-import {RequestHandler} from 'express-serve-static-core';
+import {FileUploadHandler} from './types';
 
-export const FILE_UPLOAD_SERVICE = BindingKey.create<RequestHandler>(
+/**
+ * Binding key for the file upload service
+ */
+export const FILE_UPLOAD_SERVICE = BindingKey.create<FileUploadHandler>(
   'services.FileUpload',
 );

examples/file-upload/src/services/file-upload.service.ts

@@ -9,10 +9,10 @@ import {
   config,
   ContextTags,
   Provider,
-} from '@loopback/core';
-import {RequestHandler} from 'express-serve-static-core';
+} from '@loopback/context';
 import multer from 'multer';
 import {FILE_UPLOAD_SERVICE} from '../keys';
+import {FileUploadHandler} from '../types';
 
 /**
  * A provider to return an `Express` request handler from `multer` middleware
@@ -21,15 +21,15 @@ import {FILE_UPLOAD_SERVICE} from '../keys';
   scope: BindingScope.TRANSIENT,
   tags: {[ContextTags.KEY]: FILE_UPLOAD_SERVICE},
 })
-export class FileUploadProvider implements Provider<RequestHandler> {
+export class FileUploadProvider implements Provider<FileUploadHandler> {
   constructor(@config() private options: multer.Options = {}) {
     if (!this.options.storage) {
       // Default to in-memory storage
       this.options.storage = multer.memoryStorage();
     }
   }
 
-  value(): RequestHandler {
+  value(): FileUploadHandler {
     return multer(this.options).any();
   }
 }

examples/file-upload/src/types.ts

@@ -0,0 +1,8 @@
+// Copyright IBM Corp. 2020. All Rights Reserved.
+// Node module: @loopback/example-file-upload
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {RequestHandler} from 'express-serve-static-core';
+
+export type FileUploadHandler = RequestHandler;