@atscript/moost-validator – API Reference

@atscript/moost-validator bridges Atscript-annotated types with the Moost pipeline system. It exposes a handful of helpers; everything else (advanced options, CLI usage, custom plugins) lives in the Atscript documentation.

Exports

Export	Type	Summary
validatorPipe(opts?)	TPipeFn	Validates every value whose design type was generated by Atscript (type.validator(opts).validate(value)).
UseValidatorPipe(opts?)	Decorator	Syntactic sugar for attaching validatorPipe() to classes, methods, or parameters.
validationErrorTransform()	TInterceptorDef	Converts ValidatorError into HttpError(400) so clients see a structured validation response instead of 500.
UseValidationErrorTransform()	Decorator	Shortcut for applying validationErrorTransform() at controller/handler level.

All exports are tree-shakeable. Peer dependencies: moost, @atscript/core / @atscript/typescript, and @moostjs/event-http (required by validationErrorTransform / UseValidationErrorTransform, which build an HttpError).

validatorPipe(opts?)

Attach once globally or locally when you need validation.

import { validatorPipe } from '@atscript/moost-validator'

app.applyGlobalPipes(validatorPipe())

opts accepts any subset of TValidatorOptions (e.g. { partial: 'deep', errorLimit: 50 }). Options are forwarded directly to Atscript’s validator.

UseValidatorPipe(opts?)

import { Controller } from 'moost'
import { Body, Post } from '@moostjs/event-http'
import { UseValidatorPipe } from '@atscript/moost-validator'
import { UpdateUserDto } from './update-user.dto.as'

@Controller('users')
export class UsersController {
  @Post()
  @UseValidatorPipe({ partial: true })
  async patch(@Body() dto: UpdateUserDto) {}
}

validationErrorTransform()

Without this interceptor a failed validation becomes an unhandled error (500). With it, Moost responds with 400 Bad Request and the validator details.

import { validationErrorTransform } from '@atscript/moost-validator'

app.applyGlobalInterceptors(validationErrorTransform())

Example response:

{
  "statusCode": 400,
  "message": "email: Invalid email",
  "error": "Bad Request",
  "_body": [
    { "path": "email", "message": "Invalid email" }
  ]
}

The message is the first failing rule ("<path>: <message>"); the full error list is under the _body key.

UseValidationErrorTransform()

import { UseValidationErrorTransform } from '@atscript/moost-validator'
import { CreateUserDto } from './create-user.dto.as'

@Post()
@UseValidationErrorTransform()
async create(@Body() dto: CreateUserDto) {}

Apply alongside UseValidatorPipe() when you want handler-level configuration instead of app-wide defaults.

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Need more? See the validation overview for workflow guidance and the Atscript docs for DTO authoring, CLI usage, and plugin recipes.