Nestjs custom validator. I'm using class-validator.

Nestjs custom validator. We can basically use Pipes, a feature .

• Nestjs custom validator It will allow class-validator to use NESTJS dependency injection container. We can move For this answer, I'll take a guess and assume that you use the ValidationPipe provided in the NestJS' documentation, or a close derivative. However, there is need to I have been working to validate a request using the class-validator, and NestJS validation plus trying to validate the header contents. This article will guide you through the process of validating matching Today, I am trying to figure out how to validate a Sign Up form in the backend side (NestJS) of the app. A better validation pipe for NestJS. While Nest provides a robust built-in ParseIntPipe and ValidationPipe, let's build simple custom versions of . we should create a new class CustomValidationPipe, this class I'm trying to write a custom validator. This what I have: DTO: class PositionDto { @IsNumber() cost: number How do I use the validation-pipe skipMissingProperties option along with class-validator decorators for the ones that do get passed in? With the following code, if I make an update request with other parameters but exclude 'name' from the body, the class validator throws errors from the DTO level. This stems from the necessity to streamline data validation in such projects. From npm@6 the dependency tree is flattened, which is required by Fork of the class-validator package. I want to allow properties to accept values like null, '' (empty string), or undefined without validation. However, there is need Class Validator is a popular JavaScript library that allows you to validate objects by defining custom validation rules using TypeScript classes. This behavior is achievable by passing a custom exceptionFactory to the original pipe, but I found myself writing the same exception factory for each one of my projects, so I made this package to do the job. Yet, the drawback is you will have to create a DTO for each API. 'file-type' analyzes buffer of files, so it detects Pipes only work for @Body(), @Param(), @Query() and custom decorators in the REST context. parse to parse the string and check its validity. example for good params: pass validation any-endpoint? All right, so if you really want to send a query in that format, you can nestjs DbValidator Module has some database check validation - AyubTouba/nestjs-dbvalidator Parameter Description isExistDb Check if the value is already exist in database isUniqueDb Check if the value is unique in database isLowerDb I use class-validator for my Nestjs. The official document of NestJS suggests to validate requests with the Validation Pipe. I want the file not to be saved if there are problems with validation. Custom validation that checks user existence by email against a 3rd party source. Nestjs custom class-validator decorator doesn't get the value from param 1 class-transformer @Type() decorator doesn't work Hot Network Questions Why do some claim that the law of non-contradiction is non-trivially unprovable? Am I correct in To validate the array, create a dedicated class which contains a property that wraps the array, or use the ParseArrayPipe. You can disable option language by override the message, in this case the Allows use of decorator and non-decorator based validation. @IsNotEmpty() @IsEnum Custom interceptor never crossed my mind. It always returns the field name. You need to tell to transform your string format to Date. However, I also have a global validation pipe that I apply for all incoming requests (bodies, headers Introduction Validating incoming data is crucial for any backend application. Note: Please use at least npm@6 when using class-validator. But I Thanks to @JayMcDoniel's comments, and guidence. Hello friends, I would like to demonstrate how to perform custom validation with the database in NestJs along with its unit tests. A progressive Node. They all make the same mistake. Check for existance of generateGroups method in the DTO and collect all groups by calling it and passing groups to the ValidationPipe instance. Latest version: 0. It seems to me I'm supposed to create a custom validator / decorator in this case. . Decorator-based property validation for classes. You can achieve that using Type decorator from class-transformer. The Nestjs custom class-validator decorator doesn't get the value from param Load 7 more related questions Show fewer related questions Sorted by: Reset to default Know someone who can answer? Share a link to this question via email, Twitter, or Facebook Create a Header Custom Validation with NestJS and class-validator Related 17 NestJS - Validating body conditionally, based on one property 2 Adding validation for required params in nestjs using class-validator 1 transform value if falsy 5 NestJS/Class 2 0 In nestjs, in order validate query parameter of startDate and endDate 1, sartDate must before endDate, here is custom validator @ValidatorConstraint({ name: 'isBefore', async: false }) export class IsBeforeConstraint implements ValidatorConstraintInterface { validate I now have to write a custom validation pipe. To validate email I need IsEmail decorator and to validate phone number I need IsPhoneNumber decorator in to validate them separetly. I see many similar questions in the StackOverflow. @IsOptional() NestJS: How to access both Body and Param in custom validator? 2 Adding validation for required params in nestjs using class-validator 4 NestJs - Class-validator not learn about how to do Prisma custom runtime validation in model level My existing applications are implemented by to it. That or I changed the config somewhere. How do I validate this value using class-validator current code import It's not very in NestJS way, but probably the single option to use is validate DTO inside strategy, that your guard is using: import { PassportStrategy } from '@nestjs/passport'; import { Strategy } from 'passport-strategy'; import { validate } from 'class-validator'; import I have created a custom validator which aims to check that a value does not already exist for an entity and a given field. And I used it frequently. Making statements based on opinion; back them up with If you're needing to validate the slug with your custom rules you have one of two options make a custom pipe that doesn't use class-validator and does the validation directly in it. The framework class-validator allows use of decorator and non-decorator based validation. Provide details and share your research! But avoid Asking for help, clarification, or responding to other answers. useGlobalPipes(new ValidationPipe()); inside appmodule. Maybe it will help someone. No, you can't be sure of the sequential order of async functions. However for some reason I can't get it running with the FileTypeValidator. My &quot;AppState&quot; enum has following possible enum values: export enum AppState { SUCCESS, ERROR, RUNNING } I have a UpdateAppStateDTO with an appState which should accept every enum You could probably create a custom pipe to do the validation for you, and if you have two types you're probably going to have to. js framework for building efficient, scalable, and enterprise-grade server-side applications with TypeScript/JavaScript 🚀 - nestjs/nest Maybe someone know how to make custom unique validator with class-validator in nest. There are 23 other projects in the npm registry using @nestjs/class-validator. @Post() createBulk( @Body(new ParseArrayPipe({ items: CreateUserDto })) createUserDtos: CreateUserDto[], ) { return 'This action adds new In this post, we’ll explore how NestJS Global Pipes and class-validator work together to elevate your application’s data Custom Validation In cases where certain routes have unique I build nestjs with a typescript project and I'm trying to validate filters query params. class DateValidate Fork of the class-validator package. Use @Param() { slug }: CreatePollDto. That's why class-validator is complaining not Date instance. useContainer(app. import { IsOptional, ValidateIf, ValidationOptions } from 'class-validator' export function IsOptionalNonNullable you have three solutions for it: Continue Using DTOs, Custom Validation Pipe, hybrid: The decision largely depends on your project's specific needs and your team's familiarity with these patterns. Because if you are using the DTO with the ValidationPipe it will not have access to the execution context. However, I am not sending You don't have to pass parameter name to @Param decorator when you want to use class-validator to validate params, So change it to @Param() params: ClientDTO instead. Ex: file is not empty (It would be great if also implement file must be image). I need to conditional validate an input filed in nestjs, class-validator. js to perform validation. ts add those line inside imports:[] ConfigModule. In the request body I have a field called isEmailOrPhone. ts import { Injectable } from "@nestjs/common"; import Stack Overflow for Teams Where developers NestJS is a web framework that supports natively TypeScript out of the box. However most of this code is boilerplate, let’s check the most interesting lines. I'm using passport so the user is attached to the context and in every request I have the following decorator (please note I'm using After this, you will be able to access request data when validating body in custom validator via validationArguments. ts, add the following line. email, username, etc. In my case I compose ValidationPipe with custom transform logic. In this case, you are calling the file upload interceptor, letting that code run as needed, and then validating your I'm trying to validate nested objects using class-validator and NestJS. Technically, you could make a custom decorator for req and res and get pipes to run for them. select(AppModule), {fallbackOnErrors: true}); Then you need to add your UniqueValidator to your module like an @Injectable() class I want to build a custom validator for NestJs (using v10) that will allow doing following Use Zod schema to validate Allows Creation of Dto from Zod Schema Works with File Upload (Nest's built-in Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers To create a custom validator, we have to define a new class that implements the ValidatorConstraintInterface from class-validator. The solution that worked for me was to override it for a specific param decorator. My basic interfaces are all working, but now I am trying to c I do that, as you can see in the controller. We can basically use Pipes, a feature Nest. You can read about it here. Also, this will allow you to have Nestjs custom class-validator decorator doesn't get the value from param 1 Nestjs class-validator nested object validation failure 2 Nestjs class validator dto validate body parameters Load 7 more related questions Sorted by: Reset to Obviously – it doesn't work, otherwise this article wouldn't be here. object. Nestjs custom validation pipe Undefined 2 NestJs validation pipe not working properly Hot Network Questions Are uncovered cord plugs safe to use in the snow? Designing a Block Cipher with a One-Way Function How to Create Tracing light through a Afterwards you may have custom validation pipe which should have execution priority over global pipe. Class-validator works on both browser and node. I m building a NestJS project using Prisma ORM, and after some tutorial and check on the subject, I don't see (or seem to understand) the use of DTO here, when we could use the Prisma Generated Type It's seems to be a duplication of what we already did in the I have a NestJS application that uses passport, and I'd like to add a @User param decorator to get the user in the request more easily, similarly to this example. I want to know how can I extend it so that I can call it with the below options Edited: I have referred the below link of the github file and have developed my own pipe but there still seems to be Nestjs class-validator nested object validation failure Hot Network Questions Wonderful animations on a YouTube channel made with LaTeX I develop a NestJS entrypoint, looking like that: @Post() async doStuff(@Body() dto: MyDto): Promise<string> { // some code } I use class-validator so that when my API receives a request, the payload is parsed and turned into a MyDto object, and validations present as annotations in MyDto class are performed. – Amiga500 Commented Feb 13, 2022 at 20:06 nestJS class-validator: change requirement of property based on another property 0 How can I resolve nestjs class-validator Creating custom decorators makes working with validators a breeze, NestJs gives us registerDecorator to create our own. we provide it with the validator which is the IsValidPasswordContraint we I’ve been writing some NestJS codes lately and I seems to love its first-party integration with TypeORM. for the ValidationPipe to instantiate it using the class-transformer module, resulting in the class-validator module to Nestjs custom class-validator decorator doesn't get the value from param Hot Network Questions Children's book from the late 80's early 90's with Ostrich drawn on every page How to tell if a model is identifiable? Question on the I need to understand Hello i am recently new on NESTJS and i need help to solve this problem. because the DTO method you used turns all parameters (not just :client) into a single data class. I am in the process of working out a custom validator to be used to verify if a value exists in the database I managed to get the code to work by using getConnection() from the typeorm package. Custom validate function using class-transformer and class-validator packages, which 2022-03-06T11:00:00. Outcome: didn't work, had to start defining the pipe on every controller method, a NestJS simplifies this process with ValidationPipe, a powerful tool to seamlessly validate input data in your server-side To use the custom validator, decorate your DTO properties accordingly: import { Validate } from 'class-validator'; import export class While I have looked into the IsIn code on class-validator, how to convert this for NestJS is what I am unsure of. This is my custom validation decorator, the process of creating one is described in the docs. It is built with and fully The class-validator library provides us with several decorators that can Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. js is a powerful and flexible Node. Then, we NestJS has default FileTypeValidator, you can export it from '@nestjs/common'. However, when it comes to unique validation, it seems that we need to create a custom validation by our self. Example that will Quá trình validation sẽ sử dụng ValidationPipe của NestJS, và nó cần sự kết hợp của class-validator và class-transfomer nên chúng ta phải cài đặt cả 2 package này. I try in following way: Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers I am trying to make a custom decorator validator using class-validator in a Nest. The ValidationPipe makes use of the powerful class-validator package and its declarative validation decorators. . I created a custom decorator that allows a field to be undefined, but wont let it pass validation as null. I created a library you can use this. is it the correct approach in nest ? or i should do this role based validation in service, and if it is okey then how to do this complex validation in class validator or should i have the same problem. There is a validateif decorator but how to add another validation in else section? For example: if first input was email use email decorator if it was phone match my regex. If the input is not v Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers With class-validator you have the options of Conditional Validation and of Group Validation, or you could always create a custom pipe and use AJV as you are used to. import { ExceptionFilter, Catch I think at one point NestJs use to always return ValidationErrors, but in the latest version they defaulted to their own exception filter. I'd like to add validation rule in typeorm and nest. Nestjs custom class-validator decorator doesn't get the value from param 2 Nestjs class validator dto validate body parameters 0 NestJs class-validator accepts empty payload Hot Network Questions 1970's short story with the last garden on top of a Nestjs custom validation pipe Undefined 3 NestJs validation pipe not working properly Load 7 more related questions Show fewer related questions Sorted by: Reset to default Know someone who can answer? Share a link to this question via email, Twitter, or . So I created my own validator which based on 'file-type'. For instance, let’s create a rule to validate email addresses: import { Validator} from 'class-validator'; class EmailValidator extends Validator { validate (value: First please ignore above answers. So, there is basically no simple way to get request object data in custom validation constraint. Thet's why you have validateSync method in class-validator package. I am trying to access to Request object from within a Validation Pipe in nestjs In order to verify uniqueness of certain fields, I require the ID/UUID parameters supplied with PUT/PATCH request (not We can create a Pipe and access request object. select(AppModule), { fallbackOnErrors: true }); However i don't know if it's the best way to do it I'm using the built in NestJS ValidationPipe along with class-validator and class-transformer to validate and sanitize inbound JSON body payloads. In NestJS, you can create custom validators by implementing the ValidatorConstraintInterface and using the decorator. Nest. Install class-transformer package, if you haven't done it yet. js has provided us with an in-built Validator pipe. listen(3000); Also, make sure to import Today I have for you a quick and short article. class-validator works on both browser and node. ts. Relied heavily on this I want to override the global validator pipe that I already had running and use my custom one for just that method. This requires us to implement two methods: validate → Contains your validation logic and must return a boolean defaultMessage . In NestJS, nested object validation can ensure the integrity and structure of the data your app handles. The problem is that i validate Dto and if something goes wrong the file is saved anyway. You can find the relevant documentations here. Your updateEmployee method's argument data type is Partial, which doesn't emit any type metadata. There's a brief mention here, but that should definitely get added to the docs. class-validator also provide us an examples for this. package, if you haven't done it yet. Here is a short explanation made by NestJS creator, Kamil Myśliwiec: Ok. my entity and dto is following. To create a custom validator, we have to define a new class that In this tutorial, we’re going to implement IsUnique custom validation in Nestjs to check if a database value (e. But for some reason It doesn't work in NestJS! Here is an easy solution. so when I call auth/register, the class-validator automatically check POST and validate all fields, and in case of exception it returns: { error: 'Bad Request', message: ['password too weak'] statusCode: 400 } that's good, but if I generate a custom exception: I have a custom class-validator rule: import { Injectable } from "@nestjs/common"; import { ValidatorConstraint, ValidatorConstraintInterface, ValidationArguments } from "class-valid Stack Overflow for Teams Where developers NestJs + class-validator validate either one optional parameter Hot Network Questions Intermediate disc efficiency with induction stove It is a must to add validation to all your APIs to avoid unexpected usage. forRoot({ isGlobal: true, envFilePath: '. ) is unique or not, using class-validator. This assumes that everything will be sent via Nestjs has built-in compoments named Exception filters, if you want to decorate your response in case of exceptions. js platforms. 0. Since its porpuse is to edit a profile picture of a user I need to validate the file to be an image. Internally uses validator. In this tutorial, we’re going to implement IsUnique custom validation in Nestjs to check if a database value (e. In this comprehensive guide, I, as an expert in web development Create a Header Custom Validation with NestJS and class-validator 6 NestJs - Validate request body using class-validator having 2 options for body class I am using class-validator in a NestJS project and facing an issue regarding validation. Custom Input validation in nestjs Ask Question Asked 1 year, 2 months ago Modified 10 months ago Viewed 379 times 0 I have the following DTO: export class InputDTO { value1: string; value2: string: } I want to do validation in such a way Custom validation pipes are a powerful feature of NestJS that allow you to create custom validation rules that are not supported by the built-in validation pipe. Nestjs custom class-validator decorator doesn't get the value from param Hot Network Questions Using NET to create QGIS Plugin How to set large numbers of programmatically generated colors in lightning-datatable cells? Does a Familiar? Why am Overriding the global validation pipe is tricky. js, offers a robust ecosystem for creating scalable and maintainable web applications. We’ll see how to query the database in our custom This is where our Custom validator comes in. If you want separate validations, you'll need a Joi schema for each validation and you'll need to run the validation in the constructor (or a method called from the constructor) of each service. Find out the three commonly used techniques for input validation in production grade NestJS applications Nest. import { IsEmail, IsNotEmpty } from 'class-validator'; export class CreateUserDto { @IsEmail() email: string; @IsNotEmpty() password: string; } With these rules in place, if a request hits our endpoint with I`m uploading a file using FileInterseptor, but along with the file I also pass some createDto. For those who are not familiar with NestJS, it is a framework I tried a few things class-validator is one of them. npm install exonerate for details visit here here in main. In your main. And even without NestJS, they Custom Validation Rules You can define custom validation rules using Class Validator’s Validator class. Contribute to overnested/nestjs-better-validation development by creating an account on GitHub. I've already tried following this thread by using the @Type decorator from class-transform and didn't have any luck. js to perform validation with multi-languages messages supported. I want only filter keys and values can pass validation. ts add app. For the conditional validation you could create validations based on type and then let class-validator take care of the rest Create a Header Custom Validation with NestJS and class-validator 2 NestJs authentication with JWT strategy - add validation option of "ignoreNotBefore" Hot Network Questions What would cause species only distantly related and with vast morphological I'm using NestJS 7. Under the hood, it uses the Express framework and can also be configured to use Fastify. You can still call the appropriate class-transformer and class-validator methods inside of the class too. ts import { useContainer } from 'class-validator'; useContainer(app. The following snippet could be helpful for writing your own filter. I think you should use something like ClsModule from the nestjs-cls library this will allow you to get variables from the request. useGlobalPipes(new ValidationPipe());. ts, and define a new class: import {ValidatorConstraint, ValidatorConstraintInterface, ValidationArguments} from 'class-validator'; @ ({name: , : }) I'm trying to use as much as possible the nestjs ConfigModule, its validation mechanisms and its services but to also be able to use other custom services across the board. 2 and have globally enabled validation pipes via app. NestJS is a web framework that supports natively TypeScript out of the box. Allows use of decorator and non-decorator based validation. It works really well, even for nested structures but in my case I'd like to have the body property based on some conditions. I'm trying to find a nice way to validate a body using DTO (using the brilliant class-validator and class-transformer libraries). If you don’t like the official approach, you NestJS, a powerful framework for building server-side applications with Node. This can be done by using the two classes ValidatorConstraint and ValidatorConstraintInterface provided by the class validator. In order to use class-validator in I’ve been writing some NestJS codes lately and I seems to love its first-party integration with TypeORM. By integrating Class Validator We can create a custom validator to enforce a specific rule on what a valid password should be. I'd like to I created a custom validation pipe where I want to add some custom logic. 000Z this value is a String type. I found few articles in internet, but however those implementations was not reusable. I'm using class-validator Tagged with nestjs, typescript, javascript, node. I could be wrong, but I did have an array of ValidationErrors coming across at one point. Custom pipes # As mentioned, you can build your own custom pipes. I have created a validator that add parent object in each child: import { Exclude } from 'class-transformer'; import { Validate, ValidationArguments, ValidationOptions, ValidatorConstraint, ValidatorConstraintInterface, } from 'class-validator Nestjs custom class-validator decorator doesn't get the value from param 1 Nestjs class-validator nested object validation failure 2 Nestjs class validator dto validate body parameters Hot Network Questions Milky way from planet Earth Gack Ids Validation with data transfer objects (DTO) and the class-validator package is easy. Is this correct? Or is there a better way? I'd like to change the status code during the validation stage. js is a progressive Node. The file is handled with Multer. g. At the beginning, I was going to inject directly in my validator the entity I need, but I don't like this solution, because it forces me to create a info Hint The ValidationPipe is exported from the @nestjs/common package. We’ll see how to query the database in our custom According to this issue (you can't inject a dependency) You should to add in your main. I decided it's not enough safety for my app. js framework for building server-side applications. Great suggestion. The ORM already has lots of validators one can add to entities. The ValidationPipe provides a convenient approach to enforce validation Framework provides several ways for validation data coming with requests. In the DB I have a column name time and it's type time, On my code I'm using nestjs with class-validator and the user send this value for time 10:13:06 ( Assuming it is in 12h format ). I write pipe which validate all values, and exclude this For single query param usage, you can play with this example: import Nestjs custom validation pipe Undefined 0 secretOrPrivateKey must have a value in @nestjs/jwt Hot Network Questions Is "Bich" really Latin for "generosity"? Looking for a time travel short story about a woman who makes small Would it be Schema validation The @nestjs/config package enables two different ways to do validations: Using Joi, a data validator for JavaScript. This is the code of the decorator import { InjectRepository } from '@nestjs/typeorm'; import { registerDecorator, ValidationOptions, ValidatorConstraint In conclusion, my research into Nest JS and the implementation of custom validation using the ValidatorConstraintInterface revealed a powerful capability to extend the framework’s validation mechanism based on specific requirements. In the realm of web development, email validation plays a pivotal role in data integrity and security. I am trying to validate data that might have a length of 12 or 32 digits (old system, new system), but not other lengths, so the current @Length() is not sufficient. You configure these settings via a configuration object passed to the pipe. We can create another to ensure that the username is unique. You can use the validateSync method instead of the regular validate method to perform a simple non Nestjs custom class-validator decorator doesn't get the value from param 2 NestJs + class-validator validate either one optional parameter Hot Network Questions Identify a kids' story about a boy with disfigured hands and super strength defeating alien What's happening here has to do with the Execution order of the NestJS Request Cycle, namely, how interceptors are called and fired before pipes are. Use custom pipes if you want to validate each parameter one by one. e. This tutorial will explore how to apply validation rules seamlessly in your NestJS I am using class-validator for validate data, I need to implement validation for file upload. pipe. js based application. context You can easily adjust the above to access the context when validating params or query, although I find it I'm trying to create custom validator for my input class in NestJS. By following the steps outlined in this article, you can create your own custom validation pipes and use them to validate incoming data in your NestJS applications. , in nest it will be in validationPipe. JS project. They do not see two different processes validation and transformation nestjs From the docs If your field is an array and you want to perform validation of each item in the array you must specify a special each: true decorator option If you want to be able to validate maps you could write a custom decorator and pass in a list of class-validator functions to validate the keys and values. I have Hi friends, In this post, I am going to explain custom validation with the database in NestJS. js. the problem consist that i need on the validation pipe to have access to the token of the request to call antoher api ( with the same token ) and using the HttpModule to check if the id sent I am almost ready to create my solution with a custom validator. Because this pipe uses the class-validator and class-transformer libraries, there are many options available. npm i --save class-validator class-transformer Mình sẽ sử dụng cho toàn bộ ứng dụng nên sẽ. But there is a way around! Nestjs custom class-validator decorator doesn't get the value from param 1 class-transformer @Type() decorator doesn't work Hot Network Questions Which circle is bigger? Does it make sense to create a confidence interval referencing the Z Hint Also, see Validation techniques for extensive examples of validation pipes. When sending a request with a null zip_code, custom validation Decorator is not triggered than this field is set to null into the DB for this record (on create or How to create custom field validation decorators in NestJS with GraphQL Ask Question Asked 3 years, 2 months ago Modified 2 years, 10 months ago Viewed 2k times 0 I'm working on a NestJS API with apollo-server-express and I have @InputType() export Nestjs custom class-validator decorator doesn't get the value from param 2 Nestjs class validator dto validate body parameters 0 How can I resolve nestjs class-validator Hot Network Questions Would reflected sunlight suffice to read a book on the surface of I am using class validator in nest js validate the request data. In this post, I will share the process of creating and publishing a custom class validator as an NPM package for validating user data in various projects, particularly in Korean contexts like user registration. I have an DTO: export default class CatDto extends BaseDto { @IsNotEmpty() @Expose() name: string; @IsNumber() @Expose() age: number; } The age ca Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers Nestjs custom validation pipe Undefined 3 NestJs validation pipe not working properly Hot Network Questions Horizontal arrow between two vertical arrows How to do a batch of changes in `about:config` in the Firefox? What explains the definition of I have two validator classes NameMinLengthValidator and NameMaxLengthValidator import { ValidatorConstraint, ValidatorConstraintInterface, ValidationArguments } from 'class-validator'; @ NestJs + class-validator validate either one optional parameter Hot Network Questions The Desktop, Downloads and Documents folders have disappeared from the Sidebar How do I validate someObject? Its value is a plain JS object, just some arbitrary JSON data, so it's NOT another DTO. If maintaining a clear separation and leveraging existing NestJS Let’s start by setting up a new custom validator that would potentially require some data fetching or complex logic provided by a service. 4, last published: 3 years ago. But if there's any other value, it should go through the validation decorators. This is what I have done: // is-building-id-provided. 13. In a NestJS application, this kind of validation isn't natively supported by popular packages like class-validator. all kind of complex validation logic before the controller, i. Honestly, as validation can be pretty heavy, I would say getting it out of the way at start up, all in the same place, is preferable just because it keeps everything together. validator. Do you have a suggestion on how to approach this problem? – fmagno I have problems with regards to creating custom messages using the class-validator. To do this, I'm using postcss. We can basically use Pipes, a feature called schema-based validation (using joi library) or integration with class-validator library through Learn how DTO validation works & how to create custom validators in NestJS with class-validator. My desired validation is following column data_type validation_rule date DATE YYYY:HH:MM begin_time TIME HH:MM I'd like to know how to addTIME type and how to validate YYY:HH:MM To inject dependencies into your custom validator, you need to wrap the AppModule with useContainer. This configures class-validator to use NestJS's DI container. Currently, I'm doing something like: export class Don't know whether this functionality exists in class-validator or not but I have implemented a simple Nestjs route inside of an controller with a file upload. js framework for building efficient, scalable, and Yo, i have store application with nestjs, i need validate mongo id, which is pass by query, the problem is that i also pass and search query. I am just wondering if exists a way to validate password and passwordConfirm matching, using class-validator package to build up You can use the @IsOptional() class-validator or the @IsDefined(value: any). select(AppModule), { fallbackOnErrors: true }); await app. Start using @nestjs/class-validator in your project by running `npm i @nestjs/class-validator`. In this article, we are going to delve more in the NestJS ecosystem with its built-in validation mechanism. export class EditOrderAddressDto implements Partial&lt;CreateOrderAddressDto&gt What you are trying to do is - to basically add logic to primitive validators provided out of the box with nest - aka - defining a custom validator. The thing is that my validation depends on an attribute of the user that is making the request. First, create a raw body custom decorator: this package based on class-validator. One scenario I'm facing is a mixture of upper and lower case property names in the inbound JSON objects. It integrates with the class-validator and class-transformer packages from typestack. But how Creating a Custom Decorator for Validation To utilize our class IsUniqueConstraint using a decorator style, we must craft a custom decorator. We will need to create a new file validation. The framework provides several ways for validating data coming with requests. But I didn't manage to make it work as intended. However, with a bit of creativity, we can craft a solution using custom decorators. If you have custom validation logic you can create a Constraint class: First create a file, lets say CustomTextLength. After using them, I concluded that I wanted to validate database (DB) relations with them. Stop me if a ready solution exists. you need to create isUnique class: import { Injectable } from '@nestjs/common' import { ValidationArguments, ValidatorConstraint, ValidatorConstraintInterface } from 'class-validator' import { EntityManager } from 'typeorm I have found the solution I had to put UseContainer in the main. But it detect file type by its extension. Heres the code: Using class-validator along with NestJS I want to validate that a user provides either propertyA or a propertyB but they don't need to provide both. env', }) in dto here is example of how to use it I have a custom validator in my NestJS application that checks if an input string is valid CSS. The example below is for the body but the principle could be applied to other decorators as well. DTOs (data transfer objects) are an ubiquitous pattern in NestJS to validate Fortunately, NestJS provides a validator that is quite simple to use. I'd like to be able to have a unit test that verifies that errors are being thrown if the improperly shaped object is provided, however the test as written still passes. I wanna my unique validator reuse in every dto for example: users, products.