@automapper/classes

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

Installation

``sh
npm i @automapper/classes
`

or with yarn:

`sh
yarn add @automapper/classes
`

$3

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

`sh
npm i @automapper/core reflect-metadata
`

or with yarn:

`sh
yarn add @automapper/core reflect-metadata
`

Usage

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

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

const mapper = createMapper({
...,
strategyInitializer: classes()
});

class User {
@AutoMap()
firstName: string;
@AutoMap()
lastName: string;

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

class UserDto {
@AutoMap()
firstName: string;
@AutoMap()
lastName: string;
@AutoMap()
fullName: string;
}

createMap(
mapper,
User,
UserDto,
forMember(
d => d.fullName,
mapFrom(s => s.firstName + ' ' + s.lastName)
)
);
mapper.map(new User('Auto', 'Mapper'), User, UserDto);
// UserDto { firstName: 'Auto', lastName: 'Mapper', fullName: 'Auto Mapper' }
`

Customization

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:

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

// example
mapper.map(user, 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:

`ts
export type ApplyMetadataFn = >(
model: MetadataIdentifier
) => TModel;

export type ApplyMetadata = (
strategy: MappingStrategy
) => 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