Zod Schema Patterns Basic Pattern import { z } from 'zod' import { createZodDto } from 'nestjs-zod' // Define Schema export const MySchema = z . object ( { name : z . string ( ) . min ( 1 ) , email : z . string ( ) . email ( ) , age : z . number ( ) . int ( ) . positive ( ) . optional ( ) , } ) // Create DTO class export class MyDto extends createZodDto ( MySchema ) { } // Partial DTO for updates export class PartialMyDto extends createZodDto ( MySchema . partial ( ) ) { } Project Custom Validators Location: apps/core/src/shared/schema/base.schema.ts import { zMongoId , // MongoDB ObjectId validation zNonEmptyString , // Non-empty string zArrayUnique , // Unique array elements zPinDate , // Pin date validation } from '~/shared/schema/base.schema' const Schema = z . object ( { id : zMongoId , title : zNonEmptyString , tags : zArrayUnique ( z . string ( ) ) , pin : zPinDate , } ) Extending Base Schemas import { WriteBaseSchema } from '~/shared/schema/write-base.schema' import { ImageSchema } from '~/shared/schema/image.schema' // Extend WriteBaseSchema (includes title, text, images, etc.) export const PostSchema = WriteBaseSchema . extend ( { slug : zNonEmptyString , categoryId : zMongoId , tags : zArrayUnique ( z . string ( ) ) . optional ( ) , } ) Common Patterns Optional Fields with Defaults z . boolean ( ) . default ( true ) . optional ( ) z . number ( ) . default ( 0 ) . optional ( ) z . array ( z . string ( ) ) . default ( [ ] ) . optional ( ) Preprocessing // Empty string to null z . preprocess ( ( val ) => ( val === '' ? null : val ) , z . string ( ) . nullable ( ) ) . optional ( ) // String to number z . preprocess ( ( val ) => ( typeof val === 'string' ? parseInt ( val , 10 ) : val ) , z . number ( ) ) Union Types z . union ( [ z . string ( ) , z . number ( ) ] ) z . enum ( [ 'draft' , 'published' , 'archived' ] ) Array Validation // Basic array z . array ( z . string ( ) ) // Length constraints z . array ( z . string ( ) ) . min ( 1 ) . max ( 10 ) // Unique elements zArrayUnique ( z . string ( ) ) Nested Objects const AddressSchema = z . object ( { street : z . string ( ) , city : z . string ( ) , } ) const UserSchema = z . object ( { name : z . string ( ) , address : AddressSchema . optional ( ) , addresses : z . array ( AddressSchema ) . optional ( ) , } ) Conditional Validation // refine for custom validation z . object ( { password : z . string ( ) , confirmPassword : z . string ( ) , } ) . refine ( ( data ) => data . password === data . confirmPassword , { message : 'Passwords must match' } ) Mapping to TypeGoose Models // Model export class PostModel extends WriteBaseModel { @ prop ( { required : true } ) slug ! : string @ prop ( { type : ( ) => [ String ] } ) tags ? : string [ ] } // Schema export const PostSchema = WriteBaseSchema . extend ( { slug : zNonEmptyString , // Maps to required tags : z . array ( z . string ( ) ) . optional ( ) , // Maps to optional field } ) Type Inference // Infer type from Schema type MyType = z . infer < typeof MySchema
// Use in Service async create ( data : z . infer < typeof MySchema
) { return this . model . create ( data ) }