bugfix(@nestjs/common) File(s)Interceptor throws http status code 500

Author: kamilmysliwiec

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 4.6.6
+### Bug Fixes:
+- **common**: `File(s)Interceptor` throws http status code 500 [#465](https://github.com/nestjs/nest/issues/437)
+
 ## 4.6.5
 ### Bug Fixes
 - **common**: `File(s)Interceptor` does not populate thrown exception [#437](https://github.com/nestjs/nest/issues/437)

src/common/interceptors/file.interceptor.ts

@@ -3,6 +3,7 @@ import { NestInterceptor } from './../interfaces/nest-interceptor.interface';
 import { Observable } from 'rxjs/Observable';
 import { MulterOptions } from '../interfaces/external/multer-options.interface';
 import { mixin } from '../decorators/core/component.decorator';
+import { transformException } from './multer/multer.utils';
 
 export function FileInterceptor(fieldName: string, options?: MulterOptions) {
   return mixin(
@@ -17,7 +18,8 @@ export function FileInterceptor(fieldName: string, options?: MulterOptions) {
         await new Promise((resolve, reject) =>
           this.upload.single(fieldName)(request, request.res, err => {
             if (err) {
-              return reject(err);
+              const error = transformException(err);
+              return reject(error);
             }
             resolve();
           }),

src/common/interceptors/files.interceptor.ts

@@ -2,6 +2,7 @@ import * as multer from 'multer';
 import { NestInterceptor } from './../interfaces/nest-interceptor.interface';
 import { Observable } from 'rxjs/Observable';
 import { MulterOptions } from '../interfaces/external/multer-options.interface';
+import { transformException } from './multer/multer.utils';
 
 export function FilesInterceptor(fieldName: string, maxCount?: number, options?: MulterOptions) {
   const Interceptor = class implements NestInterceptor {
@@ -15,7 +16,8 @@ export function FilesInterceptor(fieldName: string, maxCount?: number, options?:
       await new Promise((resolve, reject) =>
         this.upload.array(fieldName, maxCount)(request, request.res, err => {
           if (err) {
-            return reject(err);
+            const error = transformException(err);
+            return reject(error);
           }
           resolve();
         }),

src/common/interceptors/multer/multer.constants.ts

@@ -0,0 +1,9 @@
+export const multerExceptions = {
+  LIMIT_PART_COUNT: 'Too many parts',
+  LIMIT_FILE_SIZE: 'File too large',
+  LIMIT_FILE_COUNT: 'Too many files',
+  LIMIT_FIELD_KEY: 'Field name too long',
+  LIMIT_FIELD_VALUE: 'Field value too long',
+  LIMIT_FIELD_COUNT: 'Too many fields',
+  LIMIT_UNEXPECTED_FILE: 'Unexpected field',
+};

src/common/interceptors/multer/multer.utils.ts

@@ -0,0 +1,20 @@
+import { InternalServerErrorException, HttpException, PayloadTooLargeException, BadRequestException } from './../../exceptions';
+import { multerExceptions } from './multer.constants';
+
+export function transformException(error: Error | undefined) {
+  if (!error || error instanceof HttpException) {
+    return error;
+  }
+  switch (error.message) {
+    case multerExceptions.LIMIT_FILE_SIZE: 
+      return new PayloadTooLargeException(error.message);
+    case multerExceptions.LIMIT_FILE_COUNT:
+    case multerExceptions.LIMIT_FIELD_KEY: 
+    case multerExceptions.LIMIT_FIELD_VALUE: 
+    case multerExceptions.LIMIT_FIELD_COUNT:
+    case multerExceptions.LIMIT_UNEXPECTED_FILE:
+    case multerExceptions.LIMIT_PART_COUNT:
+      return new BadRequestException(error.message);
+  }
+  return error;
+}