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This is the official strategy from @automapper to work with TS/ES6 Class


npm i @automapper/classes

or with yarn:

yarn add @automapper/classes


@automapper/classes depends on @automapper/core and reflect-metadata.

npm i @automapper/core reflect-metadata

or with yarn:

yarn add @automapper/core reflect-metadata


@automapper/classes provides classes as a MappingStrategyInitializer. Pass classes() to createMapper to create a Mapper that uses classes strategy.

import { classes, AutoMap } from '@automapper/classes';
import { createMapper, createMap, forMember, mapFrom } from '@automapper/core';

const mapper = createMapper({
strategyInitializer: classes()

class User {
firstName: string;
lastName: string;

constructor(firstName: string, lastName: string) {
this.firstName = firstName;
this.lastName = lastName;

class UserDto {
firstName: string;
lastName: string;
fullName: string;

d => d.fullName,
mapFrom(s => s.firstName + ' ' + s.lastName)
); User('Auto', 'Mapper'), User, UserDto);
// UserDto { firstName: 'Auto', lastName: 'Mapper', fullName: 'Auto Mapper' }


classes() accepts two optional parameters:

  • destinationConstructor: how to construct the Destination. This is the default destinationConstructor that will be used on mapper.mapXXXX() operations. DestinationConstructor is a function with the following signature:

    export type DestinationConstructor<
    TSource extends Dictionary<TSource> = any,
    TDestination extends Dictionary<TDestination> = any
    > = (
    sourceObject: TSource, // the sourceObject used to map to the Destination
    destinationIdentifier: MetadataIdentifier<TDestination> // the Destination model
    ) => TDestination;

    // example, User, UserDto);
    // sourceObject will be "user"
    // destinationIdentifier will be "UserDto"
    // This allows you to provide a default constructor that can be based on the Source object data
    • There is a way to provide one-off custom destinationConstructor to any given Mapping when you run createMap. Read more about constructUsing
  • applyMetadata: how the strategy should apply the metadata to a model. The default should work for most cases but if you would like to customize this, you can. ApplyMetadata is a function with the following signature:

    export type ApplyMetadataFn = <TModel extends Dictionary<TModel>>(
    model: MetadataIdentifier<TModel>
    ) => TModel;

    export type ApplyMetadata = (
    strategy: MappingStrategy<MetadataIdentifier>
    ) => ApplyMetadataFn;

    // for example
    const customApplyMetadata: ApplyMetadata = (strategy: MappingStrategy) => {
    // strategy contains the Mapper which stores all the models' metadata
    return (model) => {
    // based on this model, you can extract the metadata and do as you like

    return anObjectThatHasTheMetadataApplied; // { foo: undefined, bar: undefined }

Read more about this strategy on classes documentation