Export ZodSerializationException so consumers can log serialization errors (#115)

Author: BenLorantfy

README.md

@@ -348,6 +348,18 @@ export class UserController {
 
 In the above example, despite the `userService.findOne` method returns `password`, the `password` property will be stripped out thanks to the `@ZodSerializerDto` decorator.
 
+### Logging serialization errors using `ZodSerializationException` 
+
+You can catch serialization errors using `ZodSerializationException` and log them using your preferred logger.
+
+```ts
+if (exception instanceof ZodSerializationException) {
+    const zodError = exception.getZodError();
+    this.logger.error(`ZodSerializationException: ${zodError.message}`);
+}
+```
+See the example app [here](/packages/example/src/http-exception.filter.ts) for more information.
+
 ## Extended Zod
 
 > [!CAUTION]

packages/example/src/app.module.ts

@@ -1,9 +1,10 @@
 import { Module } from '@nestjs/common';
-import { ZodValidationPipe } from 'nestjs-zod'
-import { APP_PIPE } from '@nestjs/core'
+import { ZodSerializerInterceptor, ZodValidationPipe } from 'nestjs-zod'
+import { APP_FILTER, APP_INTERCEPTOR, APP_PIPE } from '@nestjs/core'
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 import { PostsModule } from './posts/posts.module';
+import { HttpExceptionFilter } from './http-exception.filter';
 
 
 @Module({
@@ -15,6 +16,14 @@ import { PostsModule } from './posts/posts.module';
       provide: APP_PIPE,
       useClass: ZodValidationPipe,
     },
+    {
+      provide: APP_INTERCEPTOR,
+      useClass: ZodSerializerInterceptor,
+    },
+    {
+      provide: APP_FILTER,
+      useClass: HttpExceptionFilter,
+    },
   ]
 })
 export class AppModule {}

packages/example/src/http-exception.filter.ts

@@ -0,0 +1,17 @@
+import { Logger, Catch, ArgumentsHost, HttpException } from '@nestjs/common';
+import { BaseExceptionFilter } from '@nestjs/core';
+import { ZodSerializationException } from 'nestjs-zod';
+
+@Catch(HttpException)
+export class HttpExceptionFilter extends BaseExceptionFilter {
+    private readonly logger = new Logger(HttpExceptionFilter.name);
+
+    catch(exception: HttpException, host: ArgumentsHost) {
+        if (exception instanceof ZodSerializationException) {
+            const zodError = exception.getZodError();
+            this.logger.error(`ZodSerializationException: ${zodError.message}`);
+        }
+
+        super.catch(exception, host);
+    }
+}

packages/example/src/posts/posts.controller.ts

@@ -1,6 +1,6 @@
 import { Body, Controller, Get, Param, Post } from '@nestjs/common';
 import { ApiOkResponse } from '@nestjs/swagger';
-import { createZodDto } from 'nestjs-zod'
+import { createZodDto, ZodSerializerDto } from 'nestjs-zod'
 import { z } from 'zod'
 
 class PostDto extends createZodDto(z.object({
@@ -23,6 +23,7 @@ export class PostsController {
     }
 
     @Get(':id')
+    @ZodSerializerDto(PostDto)
     @ApiOkResponse({ type: PostDto, description: 'Get a post by ID' })
     getById(@Param('id') id: string) {
       return {

packages/nestjs-zod/src/index.ts

@@ -1,6 +1,6 @@
 export type { ZodDto } from './dto'
 export { createZodDto } from './dto'
-export { ZodValidationException } from './exception'
+export { ZodValidationException, ZodSerializationException } from './exception'
 export { createZodGuard, UseZodGuard, ZodGuard } from './guard'
 export { patchNestJsSwagger, zodToOpenAPI } from './openapi'
 export { createZodValidationPipe, ZodValidationPipe } from './pipe'