Added parseToInstance property

CHANGELOG.md

@@ -3,9 +3,11 @@ This file contains the changes made to the package.
 
 The sections are in descending order of the change date.
 
-## [3.3.0] - 2023-07-05
+## [3.3.0] - 2023-09-28
 ### Added
 - Support for `NativeEnum`s.
+- `parseToInstance` option to let users/consumers choose if the successful
+`zod` validation should parse to the instance of dynamically generated class.
 
 ## [3.2.0] - 2023-05-16
 ### Added

src/decorators/common.ts

@@ -46,7 +46,18 @@ export function MethodWithZodModel<T extends AnyZodObject>(
     let newDescriptor = descriptor || {}
 
     const originalFunction = descriptor?.value ?? target[ methodName ]
-    const decoratedFunction = decorateWithZodInput(originalFunction, input, model)
+
+    let decorationProps: typeof nameOrOptions
+    if (typeof nameOrOptions === 'string') {
+      decorationProps = {
+        zod: { parseToInstance: true },
+      }
+    }
+    else {
+      decorationProps = nameOrOptions
+    }
+
+    const decoratedFunction = decorateWithZodInput(originalFunction, input, model, decorationProps)
 
     newDescriptor.value = decoratedFunction
 

src/decorators/decorate-with-zod-input.ts

@@ -1,10 +1,11 @@
+import type { BaseOptions } from './zod-options-wrapper.interface'
+import type { DynamicZodModelClass } from './types'
+
 import { plainToInstance } from 'class-transformer'
 import { AnyZodObject, ZodError } from 'zod'
 
 import { BadRequestException } from '@nestjs/common'
 
-import { DynamicZodModelClass } from './types'
-
 type Fn = (...args: any) => any
 
 /**
@@ -28,14 +29,23 @@ export function decorateWithZodInput<
 >(
   originalFunction: F,
   input: T,
-  model: DynamicZodModelClass<T>
+  model: DynamicZodModelClass<T>,
+  options?: BaseOptions<T>
 ) {
   return function _modelWithZod(this: any, ...args: Parameters<F>) {
     const result = originalFunction.apply(this, args)
+    let parseToInstance = true
+
+    if (typeof options?.zod === 'object') {
+      if (typeof options.zod.parseToInstance === 'boolean') {
+        parseToInstance = options.zod.parseToInstance
+      }
+    }
+
     if (result instanceof Promise) {
       return result
         .then(output => input.parseAsync(output))
-        .then((output) => plainToInstance(model, output))
+        .then(output => parseToInstance ? plainToInstance(model, output) : output)
         .catch((error: Error) => {
           if (error instanceof ZodError) {
             throw new BadRequestException(error.issues)
@@ -48,7 +58,7 @@ export function decorateWithZodInput<
     else {
       const parseResult = input.safeParse(result)
       if (parseResult.success) {
-        return plainToInstance(model, parseResult.data)
+        return parseToInstance ? plainToInstance(model, parseResult.data) : parseResult.data
       }
       else {
         throw new BadRequestException(parseResult.error.issues)

src/model-from-zod.ts

@@ -2,7 +2,7 @@ import type { Type } from '@nestjs/common'
 import type { EnumProvider } from './types/enum-provider'
 import type { TypeProvider } from './types/type-provider'
 
-import { AnyZodObject, ParseParams, TypeOf, ZodError, ZodTypeAny } from 'zod'
+import type { AnyZodObject, ParseParams, TypeOf, ZodError, ZodTypeAny } from 'zod'
 
 import { ObjectType, ObjectTypeOptions } from '@nestjs/graphql'
 
@@ -56,6 +56,16 @@ export interface IModelFromZodOptions<T extends ZodTypeAny>
    */
   keepZodObject?: boolean
 
+  /**
+   * Indicates whether or not the successfully parsed objects should
+   * be converted to their dynamically built class instances.
+   *
+   * @type {boolean}
+   * @memberof IModelFromZodOptions
+   * @default true
+   */
+  parseToInstance?: boolean
+
   /**
    * A function that can be used for providing a default value for a property
    * that had an error during parsing.