Merge pull request #158 from conceptadev/feature/improve-exception-ha…

…ndling

feat: exceptions handling improvements

packages/nestjs-exception/src/__fixtures__/exceptions/custom-not-found.exception.fixture.ts

@@ -1,18 +1,14 @@
-import { format } from 'util';
-import { NotFoundException } from '@nestjs/common';
-import { ExceptionInterface } from '@concepta/ts-core';
-
-export class CustomNotFoundExceptionFixture
-  extends NotFoundException
-  implements ExceptionInterface
-{
-  errorCode = 'CUSTOM_NOT_FOUND';
+import { HttpStatus } from '@nestjs/common';
+import { RuntimeException } from '../../exceptions/runtime.exception';
 
+export class CustomNotFoundExceptionFixture extends RuntimeException {
   constructor(itemId: number) {
-    super(
-      NotFoundException.createBody(
-        format('Item with id %d was not found.', itemId),
-      ),
-    );
+    super({
+      message: 'Item with id %d was not found.',
+      messageParams: [itemId],
+      httpStatus: HttpStatus.NOT_FOUND,
+    });
+
+    this.errorCode = 'CUSTOM_NOT_FOUND';
   }
 }

packages/nestjs-exception/src/exception.types.ts

@@ -0,0 +1,5 @@
+import { ExceptionContext } from '@concepta/ts-core';
+
+export type RuntimeExceptionContext = ExceptionContext & {
+  originalError?: Error;
+};

packages/nestjs-exception/src/exceptions/runtime.exception.ts

@@ -0,0 +1,57 @@
+import { format } from 'util';
+import { HttpStatus } from '@nestjs/common';
+import { mapNonErrorToException } from '@concepta/ts-core';
+import { RuntimeExceptionInterface } from '../interfaces/runtime-exception.interface';
+import { RuntimeExceptionOptions } from '../interfaces/runtime-exception-options.interface';
+import { RuntimeExceptionContext } from '../exception.types';
+
+export class RuntimeException
+  extends Error
+  implements RuntimeExceptionInterface
+{
+  private _errorCode = 'RUNTIME_EXCEPTION';
+  private _httpStatus: HttpStatus = HttpStatus.INTERNAL_SERVER_ERROR;
+  private _safeMessage?: string;
+  public context: RuntimeExceptionContext = {};
+
+  constructor(
+    options: RuntimeExceptionOptions = { message: 'Runtime Exception' },
+  ) {
+    const {
+      message = '',
+      messageParams = [],
+      safeMessage,
+      safeMessageParams = [],
+      originalError,
+      httpStatus,
+    } = options;
+
+    super(format(message, ...messageParams));
+
+    if (httpStatus) {
+      this._httpStatus = httpStatus;
+    }
+
+    if (safeMessage) {
+      this._safeMessage = format(safeMessage, ...safeMessageParams);
+    }
+
+    this.context.originalError = mapNonErrorToException(originalError);
+  }
+
+  public get errorCode() {
+    return this._errorCode;
+  }
+
+  protected set errorCode(v: string) {
+    this._errorCode = v;
+  }
+
+  public get httpStatus() {
+    return this._httpStatus;
+  }
+
+  public get safeMessage() {
+    return this._safeMessage;
+  }
+}

packages/nestjs-exception/src/filters/exceptions.filter.e2e-spec.ts

@@ -1,7 +1,7 @@
 import supertest from 'supertest';
 import { HttpAdapterHost } from '@nestjs/core';
 import { Test, TestingModule } from '@nestjs/testing';
-import { INestApplication } from '@nestjs/common';
+import { HttpStatus, INestApplication } from '@nestjs/common';
 import { AppModuleFixture } from '../__fixtures__/app.module.fixture';
 import { ExceptionsFilter } from './exceptions.filter';
 
@@ -27,19 +27,24 @@ describe('Exception (e2e)', () => {
 
   it('Should return unknown', async () => {
     const response = await supertest(app.getHttpServer()).get('/test/unknown');
+    expect(response.body.statusCode).toEqual(HttpStatus.INTERNAL_SERVER_ERROR);
     expect(response.body.errorCode).toEqual('UNKNOWN');
+    expect(response.body.message).toEqual('Internal Server Error');
   });
 
   it('Should return bad request', async () => {
     const response = await supertest(app.getHttpServer()).get(
       '/test/bad-request',
     );
+    expect(response.body.statusCode).toEqual(HttpStatus.BAD_REQUEST);
     expect(response.body.errorCode).toEqual('HTTP_BAD_REQUEST');
+    expect(response.body.message).toEqual('Bad Request');
   });
 
   it('Should return not found', async () => {
     const response = await supertest(app.getHttpServer()).get('/test/123');
     expect(response.body.errorCode).toEqual('CUSTOM_NOT_FOUND');
+    expect(response.body.statusCode).toEqual(HttpStatus.NOT_FOUND);
     expect(response.body.message).toEqual('Item with id 123 was not found.');
   });
 });

packages/nestjs-exception/src/filters/exceptions.filter.ts

@@ -7,6 +7,7 @@ import {
 } from '@nestjs/common';
 import { ExceptionInterface } from '@concepta/ts-core';
 import { ERROR_CODE_UNKNOWN } from '../constants/error-codes.constants';
+import { RuntimeException } from '../exceptions/runtime.exception';
 import { mapHttpStatus } from '../utils/map-http-status.util';
 
 @Catch()
@@ -20,24 +21,47 @@ export class ExceptionsFilter implements ExceptionFilter {
 
     const ctx = host.switchToHttp();
 
+    // error code is UNKNOWN unless it gets overridden
+    let errorCode = ERROR_CODE_UNKNOWN;
+
     // error is 500 unless it gets overridden
     let statusCode = 500;
 
+    // what will this message be?
+    let message: string = 'Internal Server Error';
+
     // is this an http exception?
     if (exception instanceof HttpException) {
       // set the status code
       statusCode = exception.getStatus();
-      // are we missing the error code?
-      if (!exception.errorCode) {
-        // its missing, try to set it
-        exception.errorCode = mapHttpStatus(statusCode);
+      // map the error code
+      errorCode = mapHttpStatus(statusCode);
+      // set the message
+      message = exception.message;
+    } else if (exception instanceof RuntimeException) {
+      // its a runtime exception, set error code
+      errorCode = exception.errorCode;
+      // did they provide a status hint?
+      if (exception?.httpStatus) {
+        statusCode = exception.httpStatus;
+      }
+      // set the message
+      if (statusCode >= 500) {
+        // use safe message or internal sever error
+        message = exception?.safeMessage ?? 'Internal Server Error';
+      } else if (exception?.safeMessage) {
+        // use the safe message
+        message = exception.safeMessage;
+      } else {
+        // use the error message
+        message = exception.message;
       }
     }
 
     const responseBody = {
       statusCode,
-      errorCode: exception?.errorCode ?? ERROR_CODE_UNKNOWN,
-      message: exception.message,
+      errorCode,
+      message,
       timestamp: new Date().toISOString(),
     };
 

packages/nestjs-exception/src/index.ts

@@ -1,2 +1,12 @@
+// types
+export { RuntimeExceptionContext } from './exception.types';
+
 // filters
 export { ExceptionsFilter } from './filters/exceptions.filter';
+
+// interfaces
+export { RuntimeExceptionOptions } from './interfaces/runtime-exception-options.interface';
+export { RuntimeExceptionInterface } from './interfaces/runtime-exception.interface';
+
+// exceptions
+export { RuntimeException } from './exceptions/runtime.exception';

packages/nestjs-exception/src/interfaces/runtime-exception-options.interface.ts

@@ -0,0 +1,10 @@
+import { HttpStatus } from '@nestjs/common';
+
+export interface RuntimeExceptionOptions {
+  httpStatus?: HttpStatus;
+  message?: string;
+  messageParams?: (string | number)[];
+  safeMessage?: string;
+  safeMessageParams?: (string | number)[];
+  originalError?: unknown;
+}

packages/nestjs-exception/src/interfaces/runtime-exception.interface.ts

@@ -0,0 +1,24 @@
+import { HttpStatus } from '@nestjs/common';
+import { ExceptionInterface } from '@concepta/ts-core/src/exceptions/interfaces/exception.interface';
+import { RuntimeExceptionContext } from '../exception.types';
+
+export interface RuntimeExceptionInterface extends ExceptionInterface {
+  /**
+   * Optional HTTP status code to use only when this exception is sent over an HTTP service.
+   *
+   * Please consider this to be a hint for API error responses.
+   */
+  httpStatus?: HttpStatus;
+
+  /**
+   * If set, this message will be used on responses instead of `message`.
+   *
+   * Use this when the main message might expose
+   */
+  safeMessage?: string;
+
+  /**
+   * Additional context
+   */
+  context: RuntimeExceptionContext;
+}

packages/ts-core/src/core.types.ts

@@ -0,0 +1,3 @@
+export type ExceptionContext = Record<string, unknown> & {
+  originalError?: unknown;
+};

packages/ts-core/src/exceptions/interfaces/exception.interface.ts

@@ -1,3 +1,5 @@
+import { ExceptionContext } from '../../core.types';
+
 export interface ExceptionInterface extends Error {
   /**
    * The error code.
@@ -7,5 +9,5 @@ export interface ExceptionInterface extends Error {
   /**
    * Additional context
    */
-  context?: Record<string, unknown>;
+  context?: ExceptionContext;
 }

packages/ts-core/src/exceptions/not-an-error.exception.ts

@@ -1,4 +1,3 @@
-import { format } from 'util';
 import { ExceptionInterface } from './interfaces/exception.interface';
 
 export class NotAnErrorException extends Error implements ExceptionInterface {
@@ -12,7 +11,7 @@ export class NotAnErrorException extends Error implements ExceptionInterface {
     originalError: unknown,
     message = 'An error was caught that is not an Error object',
   ) {
-    super(format(message));
+    super(message);
     this.context = {
       originalError,
     };

packages/ts-core/src/index.ts

@@ -1,3 +1,5 @@
+export { ExceptionContext } from './core.types';
+
 export { ExceptionInterface } from './exceptions/interfaces/exception.interface';
 
 export { Type } from './utils/interfaces/type.interface';