Merge pull request #119 from dadosfera/fix/error-handling

FIX: added exception filter to catch unhandled errors

src/error/grpc-to-http-exception.filter.ts

@@ -0,0 +1,22 @@
+import { ExceptionFilter, Catch, ArgumentsHost } from '@nestjs/common';
+import { Response } from 'express';
+
+import ErrorBuilder from '../utils/ErrorBuilder';
+
+@Catch(Error)
+export class GrpcToHttpExceptionFilter implements ExceptionFilter {
+  catch(exception: any, host: ArgumentsHost) {
+    const ctx = host.switchToHttp();
+    const response = ctx.getResponse<Response>();
+
+    // return this exception directly if is already of type ErrorBuilder,
+    // else transform it using the ErrorBuilder
+    const err =
+      exception.constructor.name === ErrorBuilder.name
+        ? exception
+        : new ErrorBuilder(exception.details);
+
+    const { statusCode } = err.response;
+    return response.status(statusCode).json(err.response);
+  }
+}

src/modules/auth/auth.controller.ts

@@ -6,6 +6,7 @@ import {
   HttpCode,
   HttpStatus,
   Inject,
+  UseFilters,
 } from '@nestjs/common';
 import { ApiTags } from '@nestjs/swagger';
 import {
@@ -22,8 +23,10 @@ import {
 
 import { AuthClientService } from './auth.service';
 import { DadosferaLogger } from 'dadosfera-logs';
+import { GrpcToHttpExceptionFilter } from '../../error/grpc-to-http-exception.filter';
 
 @ApiTags('Auth')
+@UseFilters(new GrpcToHttpExceptionFilter())
 @Controller('auth')
 export class AuthController {
   logger: any;

src/utils/ErrorBuilder.ts

@@ -3,7 +3,7 @@ import { RpcException } from '@nestjs/microservices';
 
 import ErrorCodes from './errorCodes';
 
-function enrichErrorCode(code: string) {
+export function EnrichErrorCode(code: string) {
   switch (code) {
     case ErrorCodes.AUTH.WRONG_CREDENTIALS:
       return {
@@ -138,7 +138,7 @@ export default class ErrorBuilder extends HttpException {
       logger.log(code);
     }
 
-    const { statusCode, message, error, code: rCode } = enrichErrorCode(code);
+    const { statusCode, message, error, code: rCode } = EnrichErrorCode(code);
     super({ statusCode, message, error, code: rCode }, statusCode);
     this.code = code;
   }