Exceptions Library

This library provides a set of general exceptions and interceptors for exceptions to follow the same structure based on RFC7807

It can be used outside Softkit projects

Why we need it all?

• To have a unified way to handle exceptions
• To have ability to document exceptions properly in swagger
• To have a unified way to handle exceptions on client side
• To have a unified way to handle exceptions on server side and even proxy them to client side if you call internal service
• To have a unified way to handle exceptions in logs
• To have a unified way to understand what is a real exception and what is a business logic error. This allows to create an efficient and proactive support for customers.

Installation

yarn add @softkit/exceptions

You can also use @softkit/bootstrap to bootstrap your app with all default interceptors and filters.

This library is also tight to nestjs-i18n, this allows us to easily change default messaging for the library or if you are ok with what we have just use default (only english is available)

Usage

Default interceptors

• AnyExceptionFilter - will catch any exception and return http status 500
• HttpExceptionFilter - will catch any exception which is instance of AbstractHttpException and return http status from exception
• ForbiddenExceptionFilter - will catch NestJS ForbiddenException and return http status 403, but with our RFC format
• NotFoundExceptionFilter - will catch NestJS NotFoundException and return http status 404, but with our RFC format

Available exceptions

You can create your own exception it will be handled by default interceptor, and returned in a unified format. See ErrorResponse class.

import { AbstractHttpException } from '@softkit/exceptions';

export class YourException extends AbstractHttpException {
  constructor(rootCause?: unknown) {
    super(
      i18nString('exception.YOUR_EXCEPTION.TITLE'),
      i18nString('exception.YOUR_EXCEPTION.GENERAL_DETAIL'),
      HttpStatus.FORBIDDEN,
      undefined,
      rootCause,
    );
  }
}

Override wording

To override the default titles and details, you can take a localisation exception.json file from this library and inject it to your project

Load it with nestjs-i18n and substitution will be done automatically

You can also package this file to your localisation library to distribute across your organisation.

exception.json file is packaged to this repo and need to referenced and loadded in your app

if you won't load it you will see default keys for i18n